Project Deliverable: D03.2 Hydrological simulation ...

Project Deliverable: D03.2 Hydrological simulation modelling system

Programme name: Sustainable Management of Scarce Resources in the Coastal Zone

Program Areas: A3, (d)

Project acronym: SMART

Contract number: ICA3-CT-2002-10006

Project Deliverable: D03.2: Hydrological simulation modelling system

Related Work Package: WP 03 Analytical Tools, Model

Type of Deliverable: RE Technical Report

Dissemination level: Public

Document Author: Yvon MENSENCAL and Catherine FREISSINET, Sogreah

Reviewed by: Patrick SAUVAGET, Sogreah

Document Version: R 1.0

First Availability: 2003 08 31

Final Due Date: 2003 08 31

Last Modification: 25.09.2003

Hardcopy delivered to: Mrs. Cornelia Nauen European Commission, Research Directorate General SDME 1/02 B-1049 Brussels, Belgium

D03.2 , SOGREAH 2 of 74

TABLE OF CONTENTS

1 Executive Summary........................................................................................................ 3

2 An introduction to the TELEMAC system .................................................................... 3 2.1 The TELEMAC modelling system................................................................................... 3 2.2 The structure of the TELEMAC system ......................................................................... 3 2.3 Computer environment..................................................................................................... 3 2.4 Programming by the User ................................................................................................ 3

3 MATISSE: meshes generator ........................................................................................ 3 3.1 Glossary.............................................................................................................................. 3 3.2 Introduction ....................................................................................................................... 3 3.3 MATISSE Configuration.................................................................................................. 3 3.4 Contents of the Manual..................................................................................................... 3 3.5 Inputs and Outputs ........................................................................................................... 3

4 TELEMAC-2D: hydrodynamic simulation ................................................................... 3 4.1 Presentation of TELEMAC-2D software ........................................................................ 3 4.2 Theoretical Aspects ........................................................................................................... 3 4.3 Inputs and Outputs ........................................................................................................... 3 4.4 Topographical and Bathymetrical Data.......................................................................... 3 4.5 Hydrodynamic Simulation ............................................................................................... 3 4.6 General parameter definition for the computation........................................................ 3 4.7 Physical parameter definition .......................................................................................... 3 4.8 Numerical parameter definition....................................................................................... 3 4.9 Other parameters .............................................................................................................. 3 4.10 Tracer Transport............................................................................................................... 3 4.11 Drogues and Lagrangian Drifts ....................................................................................... 3 4.12 Weirs and culverts............................................................................................................. 3 4.13 Other configurations ......................................................................................................... 3

5 SUBIEF-2D: water quality simulation.......................................................................... 3 5.1 Introduction :..................................................................................................................... 3 5.2 Reminder of equations solved: ......................................................................................... 3

SMART ICA3-CT-2002-10006

D03.2 Sogreah 3 of 74 3

5.3 Water Quality in SUBIEF : .............................................................................................. 3 5.4 The files used by SUBIEF................................................................................................. 3

6 RUBENS: graphical post processor .............................................................................. 3 6.1 Analysis of results.............................................................................................................. 3 6.2 Presentation documents .................................................................................................... 3

7 SMART case studies....................................................................................................... 3 7.1 Construction, calibration, validation and exploitation .................................................. 3 7.2 Data requirement .............................................................................................................. 3 7.3 Description of the five case studies .................................................................................. 3

8 References....................................................................................................................... 3

ANNEXES ............................................................................................................................. 3

Annexe 1: Hardware and software requirements (windows)............................................... 3

Annexe 2: Implementing the codes....................................................................................... 3 TELEMAC tree structure ............................................................................................................ 3 Running a code .............................................................................................................................. 3 Processing the results .................................................................................................................... 3 Interrupting and deleting a computation.................................................................................... 3 Running Matisse and Rubens....................................................................................................... 3

Annexe 3: TELEMAC training............................................................................................. 3


D03.2 , SOGREAH 4 of 74

1 EXECUTIVE SUMMARY

The coastal zones of the Mediterranean are at the same time undergoing rapid development with growing and conflicting uses on the water resources, and at the same time subject to often irreversible degradation of these resources. An integrated and operational tool needs to be developed and implemented in order to help the local water authorities. In the frame of the SMART project, we are adapting two industrial softwares: WaterWare (D03.1) and TELEMAC (D03.2) following the requirements defined in WP01, to the five specific cases (Jordan, Egypt, Lebanon, Tunisia and Turkey) in order to propose to the end users some technical key element for the sustainable development of their coastal regions. One of the major SMART task will be to build some interfaces between the two mathematical models with a rule-based expert system for socio-economic assessment (WP02) in order to bring some operational solutions to the different conflicting uses and to propose some policy scenarios. The WP03, which is focus on the analytical tools and models, is presented in two parts:

- D03.1: implementation report dealing with WaterWare software - D03.2: implementation report dealing with TELEMAC system software.

The present D03.2 report is divided in 6 parts: - An overall presentation of the TELEMAC software,

- Four detailed description of the TELEMAC modules mainly used in the SMART project: MATISSE (grid generator), TELEMAC-2D (hydrodynamic model), SUBIEF-2D (water quality model) and RUBENS (graphical post-processor),

- A presentation of the 5 different case studies: description of the coastal zone, the pollution sources, major problems and issues, and the TELEMAC scenarios.

In the Annexes some TELEMAC technical information are presented.



2 AN INTRODUCTION TO THE TELEMAC SYSTEM

2.1 The TELEMAC modelling system

The TELEMAC system is a powerful integrated modelling tool for use in the field of free-surface flows. Having been used in the context of very many studies throughout the world (several hundred to date), it has become one of the major standards in its field. The various simulation modules use high-capacity algorithms based on the finite-element method. Space is discretised in the form of an unstructured grid of triangular elements, which means that it can be refined particularly in areas of special interest. This avoids the need for systematic use of embedded models, as is the case with the finite-difference method.

All the numerical algorithms are gathered into a single library (BIEF) that is shared by all the simulation modules. This makes for consistency throughout the TELEMAC system.

The pre- and post-processing tools are particularly powerful and user-friendly. Most of them are based on the use of Ilog/Views libraries and offer a range of extremely sophisticated functions. The grid can be generated with the generator embedded in the TELEMAC system (MATISSE module) or by others, in which case the STBTEL module acts as interface. TELEMAC has numerous applications in both river and maritime hydraulics. The system was developed by the Laboratoire National d'Hydraulique, a department of Electricité de France's Research and Development Division. It is distributed by Sogreah, which holds the exclusive rights for France. The users' club currently includes about a hundred members.

The various modules of the TELEMAC system run on both UNIX and Intel computers under Windows-NT.



2.2 The structure of the TELEMAC system

Hydrodynamics

TELEMAC-2D Two-dimensional flows - Saint-Venant equations (including transport of a diluted tracer)

TELEMAC-3D Three-dimensional flows - Navier-Stokes equations (including transport of active or passive tracers)

ARTEMIS Wave agitation in harbours

COWADIS Wave propagation in the coastal zone

BOUSSINESQ Two-dimensional flows/short waves (Boussinesq equations)

Transport/Dispersion SUBIEF-2D 2D water quality/2D suspended sediment transport

SISYPHE 2D bed load transport

SEDI-3D 2D suspended sediment transport

Pre-/post-processeurs

RUBENS Graphical post-processor

MATISSE Grid generation

STBTEL Grid interface

POSTEL-3D 2D sections through the results of a 3D simulation

In the frame of the SMART project the four following TELEMAC modules will be used: MATISSE, TELEMAC-2D, SUBIEF-2D and RUBENS.





2.3 Computer environment The simulation modules are written in FORTRAN-90, with no machine-specific language extensions. They can be run on all workstations operating under UNIX and on certain vector computers (in particular Cray and Fujitsu). A version working in the Windows-NT environment is also available.

The graphics modules (RUBENS and MATISSE) can be run on a workstation operating under UNIX with access to X_Windows and OSF/Motif libraries, and on a microcomputer running under Windows-NT. 2.4 Programming by the User Users may wish to program particular functions of a simulation module that are not provided for in the standard version in the TELEMAC system. This can be done in particular by using a number of so-called "user" subroutines, the source code of which is provided with the system. The following procedure should be followed:

- Recover the standard version of the user subroutine provided with the system, and copy it into the working directory.

- Modify the subroutines according to the model you wish to build. - Link up the set of subroutines into a single FORTRAN file that will be

compiled during the TELEMAC-2D start procedure. During this programming phase, users must access the various software variables. By using the structures of FORTRAN 90 gathered into a "module" type component, access is possible from any subroutine. The set of data structures is gathered in FORTRAN files referred to as modules. In the case of TELEMAC-2D, the file is called DECLARATION_TELEMAC2D and is provided with the software. To access TELEMAC-2D data, simply insert the command USE DECLARATIONS_TELEMAC2D at the beginning of the subroutine. It is also necessary to add the command USE BIEF. Almost all the arrays used by TELEMAC-2D are declared in the form of a structure with pointers. For example, access to the water depth variable is in the form H%R where the %R indicates that a pointer of real type is being used. If the pointer is of integer type, the %R is replaced by a %I. However, to avoid having to handle too many %R and %I, a number of aliases have been defined, such as for example the variables NPOIN, NELEM, NELMAX and NPTFR.



3 MATISSE: MESHES GENERATOR 3.1 Glossary The definitions of the main terms and concepts to be understood before using MATISSE are gathered in this glossary.

BOUNDARY CONDITION

For any given variable, a boundary condition is defined in MATISSE by a (free, imposed) type and a value of the variable.

CONSTRAINT LINE

A constraint line is a user-defined line serving as a support for nodes and segments of the future mesh. The segment will be linked to the line and shall not intersect it.

CONTOUR LINE

A contour line is a geometric line making up an outside or inside boundary of the represented domain.

CO-ORDINATE SYSTEM

A working session is defined around a working co-ordinate system. Any outside data source is related to an outside co-ordinate system, so that the data projection into the working co-ordinate system can be carried out.

CRITERIA

A criterion is a two-dimensional scalar function to be used for defining the inter-point distance. It can be either bathymetry or a scalar velocity field or a concentration from TELEMAC-2D, or even the transformation of one of these basic data, e.g. its reciprocal.

D.E.M.

The Digital Elevation Model (D.E.M.) is a mathematical tool including all the data as required for creating the mesh, especially the density map, the constraint lines, the fixed points, the inter-node distance, and so on.

DENSITY MAP

The density map is an unstructured mesh which serves as a basis for defining the criteria, then for computing the local inter-point distance through the criteria.

DISTANCE

It denotes the mesh inter-node distance as desired by the user. That distance is defined from operations made on the criteria. It is used by the MATISSE mesh generating algorithms.



ENTITY

An entity is a set of four pairs (type, value) related to each of the dependent variables (H, U, V, T) of the TELEMAC-2D hydrodynamic modelling software type is the boundary condition type, i.e. an integer which has values ranging from 0 to 6, and value is the value of the variable in the case when the boundary condition is constant on a time basis (that value is stored in the CONLIM file).

FIXED POINT

A bathymetry point can be defined as fixed by the user prior to mesh generation. Upon the mesh generation step, the fixed point will become an untouchable point. Then, it will keep the user-defined position. An outfall or even the angular points of an underwater rubble wall will often be defined as fixed points by the MATISSE user.

GEOMETRIC LINE

The concept of geometric line is useful in a number of jobs in MATISSE; the lines are represented by successive of linked segments. There are two main groups of geometric lines, namely the contour lines and the user-defined lines. The user-defined lines, in turn, consist of constraint lines and lines to be used when defining a criterion.

GROUP

A group is a sequence of boundary points (nodes belonging to the domain outline).

HARD POINT

A hard point features the minimal representation of a geometric line, primarily a contour line. The hard points are either defined manually or computed automatically upon a curve simplification step.

NODE

A node is a vertex of the grid resulting from a mesh. It is the locus where several edges of the mesh triangles meet. Note: the concept of node is related to the existence of a mesh, as opposed to the concept of point.

POINT

A point is any locus (x, y) within the 2D plane.

PROJECT

The MATISSE software is based upon the concept of project. At the beginning of a working session, the user will define his/her project either by opening an earlier project or by creating a new project.



UNTOUCHABLE NODE

An untouchable node is a node that cannot be translated through manual actions on the mesh nodes, segments or triangles (refer to Section 6). All the mesh nodes can be made untouchable.

Antonym: modifiable node

USER-DEFINED LINE

A user-defined line is a geometric line to be used upon defining constraints as imposed to the mesh generating algorithms. These constraints can be either a constraint line itself or the density map, prepared using criteria. A user-defined line can then be one of the items provided to generate a criterion.

VARIABLE

The variables related to a system of partial derivative equations are those defining the status of the modelled system. For TELEMAC-2D, they include the water height h, both horizontal components of velocity (v) and the value of plotter T. The value assumed by each of the dependent variables is a function of the position with the horizontal plane (x, y)as well as of time t. x, y and t are called independent variables. 3.2 Introduction GENERALS ABOUT THE MATISSE SOFTWARE Simulation modules of the TELEMAC modelling system are based on the resolution of partial derivative equation systems through the finite element method. That method is based upon a space discretisasion, namely the "mesh", of the computational domain. That mesh should take observe such constraints as the complexity of substructures and should take into account such physical parameters as the existence of outfalls. The investigated domain can be meshed in many different ways from these items, local constraints being taken into account or not. Among them, the so-called "optimal" constraint for both hydrodynamic and transport equations, minimizes the truncation errors and the cost (with respect to computation time). The note HE-45/95/018 (Mailteur de Delaunay piloté par une carte de tailles en vue d'une adaptation à la bathymétrie, C. BRAGIER, 1995 [01] describes a density map-driven automatic optimal triangulation method. That density map specifies a desired, local inter-node distance as a function of physical or mathematical densification criteria. If the mesh is generated automatically, the user will take actions at various levels, however, to provide his/her knowledge of geometry and hydrodynamic behaviour of the problem to be handled. For example:

- the outside contour of the computational domain,

- the islands within the domain, - geometric items to be taken into account, e.g. the shape of a

substructure (either out of the domain, e.g. a bridge pier, or within the domain, e.g. a shipping channel),

- local bathymetry,



- criteria for defining the local densification of nodes. These criteria can be defined either manually by the user or according to such external items as the result of a computation (velocity, concentration fields, etc.). Bathymetry is always taken into account as a criterion for computing the desired inter-point distance.

Mesh generation is not the only purpose of MATISSE. The latter is used as well for interactively defining the boundary conditions along the domain borders. The manual provided during the TELEMAC training describes how users can generate a mesh, handle it as they wish and define the boundary conditions of their hydrodynamic computation.

POSITION OF THE MATISSE SOFTWARE WITHIN THE TELEMAC PROCESSING SEQUENCE MATISSE software is part of a processing sequence, namely the TELEMAC system, which has a whole set of modules as necessary for constructing a model and carrying out hydrodynamic simulations of contaminant and sediment transport.

3.3 MATISSE Configuration Colours and special markers (e.g.: fixed points, selection, untouchable nodes, boundaries, etc.) of the MATISSE software can be configured using the ParamMatisse file.

3.4 Contents of the Manual The complete MATISSE manual is disposed on request. This manual aims at defining the MATISSE operating conditions for the users. It consists of eight sections dealing with the various MATISSE operating modes (the underscored words are defined in the glossary at the beginning of this manual): 1/ MATISSE use: This section provides the general approach followed for using the package. MATISSE is based on the concept of project: one can log in a mesh generation session using MATISSE, either by resuming a previous project, which was created during an earlier work session, or by opening a new MATISSE project. 2/ BATHYMETRY mode. You can gain access to sources of various kinds of bathymetry data, which can also be digitized from distinct maps. They should be read, then handled using MATISSE so that the user's "field skill" will be involved. This step results in one set of bathymetry data. Moreover, the usual cases in which modelling softwares, independent from the field data, are enabled should be readily defined through MATISSE.

3/ GEOMETRIC LINES mode: Once the bathymetry data are input into MATISSE, one will define the computational domain outline (contour lines), e.g. from the bathymetry. This MATISSE operating mode also makes it possible to define the user-defined lines, whether they are natural or not, to be used for defining the criteria on which the mesh generating algorithms will be based. All the lines as defined in this MATISSE operating mode are called geometric lines.



4/ D.E.M. mode: After the data to be used as a basis for the density map are created, you will define the items as requested for computing the desired inter-node distance. That can be achieved either manually or from outside data sources. 5/ MESH mode:

Among all the defined geometric lines, one will choose the future constraint lines to be used for generating the mesh. Subsequently, the generation is performed : the mesh is displayed on the screen. You can then return upstream and take new constraint lines into account, then assess the improvements of the resulting mesh.

Lastly, you can change manually the generated mesh in order to specify some items. On completion of these changes, automatic checks are performed to ensure a proper arrangement of the final mesh. 6/ BOUNDARY CONDITIONS mode: Once the mesh is defined, you will state the type of boundary conditions for each homogeneous segment (a Group) of the border. The choice is made using a graphics editor.

7/ Generic functions: The generic functions are those to which access is gained in any MATISSE operating mode.

8/ MATISSE files: An objective of MATISSE is to create some essential files of the TELEMAC modelling system, namely the geometry file and the boundary conditions file.

Though the sequence order of this manual's sections is consistent with the various tasks as usually performed by the MATISSE user for generating his/her mesh, the user may however return to any earlier step during his/her work.

3.5 Inputs and Outputs The various types of inputs are as follows: the meshes included in the geometry files as used by the TELEMAC computational modules. These files are accessed on reading;

- the sources of bathymetry data or geometric lines. These files are accessed on reading;

- the results of computation modules as used in the form of constraints for defining the node density. Files accessed on reading to the SERAFIN format.

- The earlier MATISSE projects for restart. The contained data can then be modified. An earlier project can also be used as a source of punctual data such as the entities for the definition of the boundary conditions or the density map. Then the project cannot be amended.

All these files and projects are optional. For example, a mesh can neither be started nor created without any data for generating simple test cases.



MATISSE generates as output two files that are necessary for the computation modules of the TELEMAC processing sequence, namely the GEOMETRY and CONLIM files (for instance, refer to the TELEMAC-2D user documentation). Moreover, MATISSE manages a workspace or "project". All the data as required for creating a mesh (geometric lines, criteria, inter-node distance, ...) shall be stored in that project.



4 TELEMAC-2D: HYDRODYNAMIC SIMULATION 4.1 Presentation of TELEMAC-2D software The TELEMAC-2D code solves depth-averaged free surface flow equations as derived first by Barré de Saint-Venant in 1871. The main results at each node of the computational mesh are the depth of water and the depth-averaged velocity components. The main application of TELEMAC-2D is in free-surface maritime or river hydraulics and the program is able to take into account the following phenomena:

- Propagation of long waves, including non-linear effects - Friction on the bed

- The effect of the Coriolis force - The effects of meteorological phenomena such as atmospheric

pressure and wind - Turbulence - Supercritical and subcritical flows

- Influence of horizontal temperature and salinity gradients on density - Cartesian or spherical coordinates for large domains

- Dry areas in the computational field: tidal flats and flood-plains - Entrainment and diffusion of a tracer by currents, including creation

and decay terms

- Particle tracking and computation of Lagrangian drifts - Treatment of singularities: weirs, dikes, culverts, etc.

- Inclusion of the drag forces created by vertical structures - Inclusion of porosity phenomena - Inclusion of wave-induced currents (by link-ups with the ARTEMIS and

TOMAWAC modules). The software has many fields of application. In the maritime sphere, particular mention may be made of the sizing of port structures, the study of the effects of building submersible dikes or dredging, the impact of waste discharged from a coastal outfall or the study of thermal plumes. In river applications, mention may also be made of studies relating to the impact of construction works (bridges, weirs, groynes), dam breaks, flooding or the transport of decaying or non-decaying tracers. TELEMAC-2D has also been used for a number of special applications, such as the bursting of industrial reservoirs, avalanches falling into a reservoir, etc. TELEMAC-2D was developed by the National Hydraulics and Environment Laboratory (Laboratoire National d’Hydraulique et Environnement - LNHE) of the Research and Development Directorate of the French Electricity Board (EDF-DRD). Like previous versions of the program, version 5.2 complies with EDF-DRD’s Quality Assurance procedures for scientific and technical programs. This sets out rules for developing and checking product quality at all stages. In particular, a program covered by Quality Assurance procedures is accompanied by a Formulation Document that describes the theoretical aspects of the software, and a Validation Document that describes the field of use of the software and a set of test cases. This latter



document can be used to determine the performance and limitations of the software and define its field of application. The test cases are also used for developing the software and are checked each time new versions are produced.

4.2 Theoretical Aspects The TELEMAC-2D code solves the following four hydrodynamic equations simultaneously:

hS)u(divh)h(uth

=+∇⋅+rr

∂∂ continuity

)uh(divh

SxZg)u(u

tu

tx ∇++−=∇⋅+rrr

ν∂∂

∂∂ 1 momentum along x

)vh(divh

SyZg)v(u

tv

ty ∇++−=∇⋅+rrr

ν∂∂

∂∂ 1 momentum along y

)Th(divh

S)T(utT

TT ∇+=∇⋅+rrr

ν∂∂ 1 tracer conservation

in which: h (m) depth of water u,v (m/s) velocity components T (g/l or °C) non-buoyant tracer

g (m/s2) gravity acceleration

νt,νT (m2/s) momentum and tracer diffusion coefficients

Z (m) free surface elevation t (s) time

x,y (m) horizontal space coordinates Sh (m/s) source or sink of fluid

Sx,Sy (m/s2) source or sink terms in dynamic equations ST (g/l/s) source or sink of tracer h, u, v and T are the unknowns.

The equations are given here in Cartesian coordinates. They can also be processed using spherical coordinates.

Sx and Sy (m/s2) are source terms representing the wind, Coriolis force, bottom friction, a source or a sink of momentum within the domain. The different terms of these equations are processed in one or more steps (in the case of advection by the method of characteristics):

- advection of h, u, v and T,



- propagation, diffusion and source terms of the dynamic equations, - diffusion and source terms of the tracer transport equation.

Any of these steps can be skipped, and in this case different equations are solved. In addition, each of the variables h, u, v and T may be advected separately. In this way it is possible, for example, to solve a tracer advection and diffusion equation using a fixed advecting velocity field.

Turbulent viscosity may be given by the user or determined by a model simulating the transport of turbulent quantities k (turbulent kinetic energy) and Epsilon (turbulent dissipation), for which the equations are the following:

kvk

t PP)kh(divh

)k(utk

+−+∇=∇⋅+ εσν

∂∂ rrr 1

vt P)cPc(

k)h(div

h)(u

t εεεε

εεεσν

ε∂ε∂

+−+∇=∇⋅+ 211 rrr

The right-hand side terms of these equations represent the production and destruction of turbulent quantities (energy and dissipation). A complete description of the theory is given in the Formulation Document.



4.3 Inputs and Outputs PRELIMINARY REMARKS During a computation, the TELEMAC-2D software uses a number of input and output files, some of which are optional. The input files are the following:

- The geometry file (obligatory) - The steering file (obligatory)

- The boundary conditions file (obligatory) - The bottom topography file

- The FORTRAN file - The open boundary file - The previous computation file

- The binary data file - The formatted data file

- The reference file The output files are the following:

- The results file - The listing printout

- The formatted data file - The binary data file

THE FILES Main files used in a TELEMAC-2D computation are described bellow. All of needed files are presented in the TELEMAC-2D manual (given to all the partners during the TELEMAC training).

The steering file This is a text file created by a text editor. In a way, it represents the control panel of the computation. It contains a number of keywords to which values are assigned. If a keyword is not contained in this file, TELEMAC-2D will assign it the default value defined in the dictionary file. If such a default value is not defined in the dictionary file, the computation will stop with an error message. TELEMAC-2D reads the steering file at the beginning of the computation.

The mesh file This is a binary file in Selafin or Leonard format, and can thus be read by RUBENS and created either directly by MATISSE or by the STBTEL module from the file(s) produced by the mesh generator. The structure of the Selafin format is described in the manual. This file contains all the information concerning the mesh, i.e. the number of mesh points (NPOIN variable), the number of elements (NELEM variable), and the number of nodes per



element (NDP variable), arrays X and Y containing the coordinates of all the nodes and array IKLE containing the table of connectivities.

This file can also contain bottom topography information at each mesh point, if such bottom topography has been interpolated during the running of the STBTEL module. TELEMAC-2D stores information on the geometry at the start of the results file. Because of this, the computation results file can be used as a geometry file if a new simulation is to be run on the same mesh.

The boundary conditions file This is a formatted file generated automatically by MATISSE or STBTEL. It can be modified with a standard text editor. Each line of the file is dedicated to one point on the mesh boundary. The numbering used for points on the boundary is that of the file lines. First of all, it describes the contour of the domain trigonometrically, starting from the bottom left-hand corner (X + Y minimum) and then the islands in a clockwise direction.

The liquid boundaries file This file enables the user to specify values for time-dependent boundary conditions (tracer flow rate, depth, velocity and concentration).

The reference file When a calculation is being validated, this file contains the reference result. At the end of the calculation, the result of the simulation is compared to the last time step stored in this file. The result of the comparison is given in the control printout in the form of a maximum difference in depth and the two velocity components.

The results file This is the file in which TELEMAC-2D stores information during the computation. It is normally in Selafin format. It contains first of all information on the mesh geometry, then the names of the stored variables. It then contains the time for each time step and the values of the different variables for all mesh points.

The FORTRAN user file Since version 5.0 of the software (the first version to be written in FORTRAN 90), this file has become optional, as TELEMAC-2D uses a dynamic memory allocation process and it is therefore no longer necessary to set the size of the various arrays in the memory. The FORTRAN file contains all the TELEMAC-2D subroutines modified by the user and those that have been specially developed for the computation. For example, time wind series could be read from an external file and imposed in the hydrodynamic computation.

This file is compiled and linked so as to generate the executable program for the simulation.

4.4 Topographical and Bathymetrical Data Topographical and bathymetric data may be supplied to TELEMAC-2D at three levels:

- Either directly in the geometry file by a topographical or bathymetric value associated with each mesh node. In this case, the data are processed while the mesh is being built using MATISSE or when the



STBTEL module is run before TELEMAC-2D is started. STBTEL reads the information in one or more bottom topography files (5 at most) and interpolates at each point in the domain.

- Or in the form of a cluster of points with elevations that have no relation with the mesh nodes, during the TELEMAC-2D computation. TELEMAC-2D then makes the interpolation directly with the same algorithm as STBTEL. The file name is provided by the keyword BOTTOM TOPOGRAPHY FILE In contrast to STBTEL, TELEMAC-2D only manages one bottom topography file. This may be in SINUSX format or more simply a file consisting of three columns X,Y,Z.

- Or using the CORFON subroutine. This is usally used for schematic test cases.

In all cases, TELEMAC-2D offers the possibility of smoothing the bottom topography in order to obtain a more regular geometry. The smoothing algorithm can be iterated several times depending on the degree of smoothing required.



4.5 Hydrodynamic Simulation PRESCRIPTION OF INITIAL CONDITIONS The purpose of the initial conditions is to describe the state of the model at the start of the simulation. In the case of a continued computation, this state is provided by the last time step of the results file for the previous computation. The tables of variables that are essential for continuing the computation must therefore be stored in a file used for this purpose. In other cases, the initial state must be defined by the user. This can be done using keywords in simple cases, or by programming in more complex ones.

Prescribing using keywords In all cases, the nature of the initial conditions is fixed with the keyword INITIAL CONDITIONS. This may have any of the following five values:

- ‘ZERO ELEVATION’: This initialises the free surface elevation at 0. The initial depths of water are therefore calculated from the bottom elevation.

- ‘CONSTANT ELEVATION’: This initialises the free surface elevation at the value supplied by the keyword INITIAL ELEVATION. The initial depths of water are then calculated by subtracting the bottom elevation from the free surface elevation. In areas where the bottom elevation is higher than the initial elevation, the initial depth of water is null.

- ‘ZERO DEPTH’: All water depths are initialised with a zero value (free surface same as bottom). In other words, the entire domain is dry at the start of the computation.

- 'CONSTANT DEPTH’: This initialises the water depths at the value supplied by the keyword INITIAL DEPTH

- ‘PARTICULAR’: The initial conditions are defined in the CONDIN subroutine. This solution must be used whenever the initial conditions of the model do not correspond to one of the four cases above.

Prescribing with the CONDIN subroutine The CONDIN subroutine must be programmed whenever the keyword INITIAL CONDITIONS has the value ‘PARTICULAR’.

The CONDIN subroutine initialises successively the depth of water, the velocities, the tracer, the k-Epsilon model and the viscosity. That part of the subroutine concerning the initialisation of the water depth is divided into two zones. The first corresponds to the processing of simple initial conditions (defined by the keyword) and the second the processing of particular initial conditions.

By default, the standard version of the CONDIN subroutine stops the computation if the keyword INITIAL CONDITIONS is positioned at PARTICULAR without the subroutine actually being modified.

The user is entirely free to fill this subroutine. For example, he can re-read information in a formatted or binary file using the keywords FORMATTED DATA FILE or BINARY DATA FILE offered by TELEMAC-2D.



When the CONDIN subroutine is being used, it may be interesting to check that the variables are correctly initialised. To do this, it is simply a question of assigning the name of the variables to be checked to the keyword VARIABLES TO BE PRINTED and starting the computation with a zero number of time steps. The user then obtains the value of the variables required at each point of the mesh in the listing printout.

Continuing a computation TELEMAC-2D enables the user to carry out a computation taking the last time step of a previous computation on the same mesh as initial state. It is thus possible to modify the computation data, such as, for example, the time step, certain boundary conditions or the turbulence model, or to start the computation once a steady regime has been reached.

In this case, it is essential for the file to contain all the information required by TELEMAC-2D, i.e. the velocities U and V, the water depth and the bottom elevations. However, in certain cases, the software is capable of recomputing certain variables from others provided (for example the depth of water from the free surface and the bottom elevation).

PRESCRIBING BOUNDARY CONDITIONS Possible choices Boundary conditions are given for each of the boundary points. They concern the dependent variables of TELEMAC-2D or the values deduced from them: water depth, the two components of velocity (or flowrate) and the tracer. The boundary conditions of functions k and Epsilon in the turbulence model are determined by TELEMAC-2D and are thus not required from the user. The various types of boundary conditions may be combined to prescribe boundary conditions of any physical type (inflow or outflow of liquid in a supercritical or subcritical regime, open sea, wall, etc.). However, certain combinations are not physical. Some boundary conditions apply to segments, such as friction at the walls, wall impermeability or incident wave conditions. However, wall definition is ambiguous if boundary conditions are to be defined by points. The following convention is used in such cases to determine the nature of a segment situated between two points of different type. A liquid segment is one between two points of liquid type. In a similar way, when a condition is being prescribed for a segment, the point must be configured at the start of the segment.

The way in which a boundary condition is prescribed depends on the spatial and temporal variations in the condition. Five types of condition may be distinguished:

- The condition is constant at the boundary and constant in time. The simplest solution is then to prescribe the condition by means of a keyword in the steering file.

- The condition is constant at the boundary and variable in time. It will then be prescribed by programming the functions Q SL and VIT (and TR if a tracer is used) or by the open boundaries file.

- The condition is variable in space and constant in time. It will then be prescribed via the boundary conditions file. In certain cases, the velocity profile can be specified using the keyword VELOCITY PROFILES.



- The condition is variable in time and space. Direct programming via the BORD subroutine is then necessary.

- The boundary condition type is variable in time. Direct programming in the PROPIN_TELEMAC2D subroutine is then necessary.

Boundary types may be connected in any way along a contour (for example, there may be an open boundary with a prescribed depth followed by an open boundary with a prescribed velocity). The only limitation is that a boundary must consist of at least two points (a minimum of four points is strongly advised).

Description of the various types of condition The type of boundary condition at a given point is provided in the boundary conditions file in the form of four integers named LIHBOR, LIUBOR, LIVBOR and LITBOR, which may have any value from 0 to 6.

The possible choices are as follows:

Depth conditions:

- Open boundary with prescribed depth: LIHBOR=5

- Open boundary with free depth: LIHBOR=4

- Open boundary with incident wave: LIHBOR=1

- Closed boundary (wall): LIHBOR=2

It should be noted that a rating curve is considered to be a condition with a prescribed flowrate. The flowrate value must then be computed explicitly as a function of the depth of water, in function Q.

Flowrate or velocity condition:

- Open boundary with prescribed flowrate: LIUBOR/LIVBOR=5

- Open boundary with prescribed velocity: LIUBOR/LIVBOR=6

- Open boundary with free velocity: LIUBOR/LIVBOR=4

- Open boundary with slip or friction: LIUBOR/LIVBOR=2

- Closed boundary with one or two nil velocity components: LIUBOR and/or LIVBOR=0

- Open boundary with incident wave: LIUBOR/LIVBOR=1

Tracer conditions:

- Open boundary with prescribed tracer: LITBOR=5

- Open boundary with free tracer: LITBOR=4

- Closed boundary (wall): LITBOR=2



Remarks:

It is possible to change the type of boundary condition within an open boundary. In that case, a new open boundary will be detected in the output control listing.

In the case of an open boundary with an incident wave, the user must fill in the INCIDE subroutine in order to introduce the wave characteristics. This boundary condition is such that, if a wave generated inside the domain leaves it perpendicular to the boundary, there will be no reflection. In other cases, reflection phenomena are possible. The type of boundary condition during the simulation may be modified with the PROPIN_TELEMAC2D subroutine.

The boundary conditions file The file is normally supplied by MATISSE or STBTEL, but may be created and modified using a text editor. Each line of this file is dedicated to one point of the mesh boundary. The numbering of the boundary points is the same as that of the lines of the file. It describes first of all the contour of the domain in a trigonometric direction, and then the islands in the opposite direction. This file specifies a numbering of the boundaries. This numbering is very important because it is used when prescribing values. The following values are given for each point (see also the section dedicated to parallel processing for certain specific aspects): LIHBOR, LIUBOR, LIVBOR, HBOR, UBOR, VBOR, AUBOR, LITBOR, TBOR, ATBOR, BTBOR, N, K

LIHBOR, LIUBOR, LIVBOR, and LITBOR are the boundary type codes for each of the variables.

HBOR (real) represents the prescribed depth if LIHBOR = 5.

UBOR (real) represents the prescribed velocity U if LIUBOR = 6.

VBOR (real) represents the prescribed velocity V if LIVBOR = 6.

AUBOR represents the friction coefficient at the boundary if LIUBOR or LIVBOR = 2. The friction law is then written as follows

ν*/* AUBORdndVorandUAUBOR

dndU

==

The coefficient AUBOR applies to the segment included between the boundary point considered and the following point (in a trigonometric direction for the outer contour and in the opposite direction for the islands). The default value is AUBOR = 0. Friction corresponds to a negative value. With the k-Epsilon model, the value of AUBOR is computed by TELEMAC-2D and the indications in the boundary conditions file are then ignored.

TBOR (real) represents the prescribed value of the tracer when LITBOR = 5.

ATBOR and BTBOR represent the coefficients of the flow relation, written:



BTBORT*ATBORdndT

+=

The coefficients ATBOR and BTBOR apply to the segment between the boundary point considered and the next point (in a trigonometric direction for the outer contour and in the opposite direction for the islands).

N represents the total number of the boundary points in the case of a non-structured mesh.

K represents the point number in the boundary point numbering.

Prescribing values using keywords In most simple cases, boundary conditions are prescribed using keywords. However, if the values to be prescribed vary in time, it is necessary to program the appropriate functions or use the open boundaries file (see 4.2.5). The keywords used for prescribing boundary conditions are the following: PRESCRIBED ELEVATIONS: This is used to define the elevation of an open boundary with prescribed depth. It is a table that contains up to 100 real numbers for managing up to 100 boundaries of this type. The values provided with this keyword cancel the depth values read from the boundary conditions file. N.B.: the value given here is the level of the free surface, whereas the value given in the boundary conditions file is the water depth.

- PRESCRIBED FLOWRATES: This is used to fix the flowrate value of an open boundary with prescribed flowrate. A positive value corresponds to an inflow into the domain. The values provided with this keyword cancel the flowrate values read from the boundary conditions file.

- PRESCRIBED VELOCITIES: This is used to fix the velocity value of an open boundary with prescribed velocity. The scalar value provided is the intensity of the velocity perpendicular to the wall. A positive value corresponds to an inflow into the domain. The values provided with this keyword cancel the values read from the boundary conditions file.

Some simple rules must also be complied with:

There must of course be agreement between the type of boundary specified in the boundary conditions file and the keywords of the steering file (do not use the keyword PRESCRIBED FLOWRATES if there are no boundary points with the LIUBOR and LIVBOR values set at 5).

For each keyword, the number of specified values must be equal to the total number of open boundaries. If a boundary does not correspond to the specified keyword, the value will be ignored (for example, the user can specify 0.0 in all cases).

Prescribing values by programming functions or using the open boundaries file Values that vary in time but are constant along the open boundary in question are prescribed by using the open boundaries file or by programming a particular function, which may be:

- Function VIT to prescribe a velocity,

- Function Q to prescribe a flowrate,



- Function SL to prescribe an elevation,

- Function TR to prescribe a tracer concentration,

- Subroutine INCIDE to prescribe an incident wave.

Functions Q, VIT and SL are programmed in the same way. In each case, the user has the time, the boundary rank (for determining, for example, whether the first or second boundary with a prescribed flowrate is being processed) and in the case of Q, information on the depth of water at the previous time step. By default the functions prescribe the value read from the boundary conditions file or supplied by keywords. Using the liquid boundaries file is an alternative to programming the functions mentioned above. This is a text file edited by the user, the name of which is given with the keyword LIQUID BOUNDARIES FILE. When TELEMAC-2D reads this file, it makes a linear interpolation in order to calculate the value to be prescribed at a particular time step. The value actually prescribed by the code is printed in the control printout.

Prescribing complex values If the values to be prescribed vary in both time and space, it is necessary to program the BORD subroutine as this enables values to be prescribed on a node-by-node basis. This subroutine describes all the open boundaries (loop on NPTFR). For each boundary point, it determines the type of boundary in order to prescribe the appropriate value (velocity, elevation or flowrate). However, there is little sense in programming BORD to prescribe a flowrate, as this value is usually known for the entire boundary and not for each segment of it. In the case of a prescribed flowrate boundary located between two solid boundaries with no velocities, the velocities on the angle points are cancelled.

N.B.: The BORD subroutine also enables the tracer limit values to be prescribed.

Prescribing velocity profiles In the case of a flowrate condition, the user can specify the velocity profile computed by TELEMAC-2D, using the keyword VELOCITY PROFILES. The following options are available:

1: The velocity vector is normal to the boundary. In the case of a prescribed flowrate, the value of the vector is set to 1 and then multiplied by a constant in order to obtain the desired flowrate (given by the keyword PRESCRIBED FLOWRATES or by the function Q). In the case of a prescribed velocity, the value used for the velocity norm is provided by the keyword PRESCRIBED VELOCITIES or by the function VIT. In any case, the velocity profile is constant along the boundary.

2: The values U and V are read from the boundary conditions file (UBOR and VBOR values). In the case of a prescribed flowrate, these values are multiplied by a constant in order to reach the prescribed flowrate.

3: The velocity vector is imposed normal to the boundary. Its value is read from the boundary conditions file (UBOR value). This value is then multiplied by a constant in order to obtain the appropriate velocity or flowrate. 4: The velocity vector is normal to the boundary and its norm is proportional to the square root of the water depth.

In the case of a flow normal to a closed boundary, it is not good to have velocities perpendicular to the solid segments (as shown in the figure hereafter) because the finite



element interpolation will generate a non-zero flow though a solid segment. In this case, it is better to cancel the velocities on the first and last points of the boundary, as shown on the following figures:

solid boundary liquid boundary solid boundary

solid boundary liquid boundary solid boundary

Thompson boundary conditions In some cases, not all the necessary information concerning the boundary conditions is available. This is usual for coastal domains where only the values of the sea level on several points are known. This kind of model is referred to as an “under-constrained” model. To solve this problem, the Thompson method uses the characteristics method to calculate the missing values. For example, TELEMAC-2D will compute the velocity at the boundary in the case of a prescribed elevation.

This method can also be used for “over-constrained” models. In this case, the user specifies too much information at the boundary. If the velocity information and the level information are not consistent, too little or too much energy is going into the model. For this, the Thompson technique computes a new value for the velocity and performs small adjustments to cancel the inconsistencies in the information. For this, the user can use the keyword OPTION FOR OPEN BOUNDARIES, which offers two values:

1: strong setting 2: Thompson method

Taking a simplified view, it may be said that, in the case of the first option, the values are “imposed”, in the case of the second option, the values are “suggested”.



Definition of types of boundary condition when preparing the mesh When using MATISSE, the boundary condition type is prescribed during the last step of mesh generation. When using the other mesh generators, it is generally possible to define the type of boundary condition during the mesh generation session, by prescribing a colour code. Each colour code corresponds to a particular type of boundary (wall, open boundary with prescribed velocity, etc.).



4.6 General parameter definition for the computation General parameter definition for the computation is done only in the steering file. Time information is supplied by the three keywords TIME STEP (real), NUMBER OF TIME STEPS (integer) and DURATION. The first defines the time separating two consecutive instants of the computation (but not necessarily two withdrawals from the results file). The total duration of the computation may be supplied by means of a number of time steps (keyword NUMBER OF TIME STEPS) or in the form of a total simulation period expressed in seconds (keyword DURATION). In the former case, the total duration is obviously equal to the time step value multiplied by the number of time steps. If a steering file contains the keywords DURATION and NUMBER OF TIME STEPS, TELEMAC-2D uses the one that produces the longer simulation. In addition, if the keyword DURATION is used and does not correspond to a whole number of time steps, TELEMAC-2D will take the integer immediately higher. The title of the computation is specified by the keyword TITLE.

CRITERIA FOR STOPPING A COMPUTATION Independently of normal time indications (number of time steps and time step value), TELEMAC-2D offers two possibilities for conditionally stopping the computation:

- Stopping when reaching a steady state. - Stopping in cases of divergence: This function is used to interrupt a

computation if there is divergence. -

4.7 Physical parameter definition A number of physical parameters may or must be specified during a simulation. If the parameter is space-dependent, it is sometimes preferable to define various zones within the mesh and then assign the parameter as a function of the zone number. This zone number may then be used in the various subroutines for specifying a space-dependent physical parameter.

FRICTION PARAMETER DEFINITION The friction law used to model friction on the bed is defined by the keyword LAW OF BOTTOM FRICTION. This may have the following values:

0 : No friction. 1 : Haaland's law.

2 : Chézy’s law. 3 : Strickler’s law.

4 : Manning’s law. 5 : Nikuradse’s law.

In the case of options 1 to 5, it is necessary to specify the value of the coefficient corresponding to the law chosen by means of the keyword FRICTION COEFFICIENT. This is of course only valid if the friction is constant in time and space.



If the friction coefficient varies in time (and possibly in space as well), it is necessary to use the STRCHE and/or CORSTR subroutines, which supply the friction coefficient at each mesh point.

MODELLING OF TURBULENCE The modelling of turbulence is a delicate problem. TELEMAC-2D offers the user four options of different complexity.

- The first involves using a constant viscosity coefficient. In this case, the coefficient represents the molecular viscosity, turbulent viscosity and dispersion.

- The second option involves an Elder model. - The third option involves using a k-Epsilon model. This a 2D model that

solves the transport equations for k (turbulent energy) and Epsilon (turbulent dissipation). The model equations are solved by a fractional step method, with convection of turbulent variables being processed at the same time as the hydrodynamic variables, and the other terms relating to the diffusion and production/dissipation of turbulent values being processed in a single step. Use of the k-Epsilon model also often requires a finer mesh than the constant viscosity model and in this way increases computation time.

- The fourth involves a Smagorinski model, generally used for maritime domains with large-scale eddy phenomena.

More detailed information on the formulation of the k-Epsilon model, the Elder model and the Smagorinski model is given in the TELEMAC-2D Formulation Document (see TELEMAC manual).

In addition, TELEMAC-2D offers two possibilities for processing the diffusion term. The option is selected by the keyword OPTION FOR THE DIFFUSION OF VELOCITIES which can take the value 1 (default) or 2. The first value selects a computation with the form ( ))U(graddiv ν ,

and the second one with the form ( ))U(gradhdivh

ν1 .

This latter option is the only one offering good mass conservation, but difficulties may occur with tidal flats.

PARAMETER DEFINITION FOR WIND AND ATMOSPHERIC PRESSURE TELEMAC-2D can be used to simulate flow while taking into account the influence of a wind blowing on the water surface. The logical keyword WIND is used first of all for determining whether this influence is to be taken into account and if so, the coefficient is then provided with the keyword COEFFICIENT OF WIND INFLUENCE. Lastly, wind speed in directions X and Y is supplied with the keywords WIND VELOCITY ALONG X and WIND VELOCITY ALONG Y

If the wind velocity varies in space and time, the user must indicate this in the METEO subroutine. Atmospheric pressure is taken into account by setting the keyword AIR PRESSURE to YES (the default value is NO). The pressure value is indicated directly in the METEO subroutine. By default, a pressure of 105 Pa (1 atmosphere) is initialised throughout the domain.



The METEO subroutine is called up if the wind or atmospheric pressure option is activated. By default, the subroutine is called up at the start of the computation (time value = 0) in order to fix the pressure at 105 Pa throughout the domain and the wind velocity at the values supplied with the corresponding keywords. The user has geometrical information on the mesh, and time information for programming any study situation, in particular winds that vary in time and space (in this case a test must be programmed for time values other than 0).

OTHER PHYSICAL PARAMETERS When modelling large areas, it is necessary to take into account the inertia effect of the Coriolis force. In this case, the value of the Coriolis coefficient (see Formulation Document) is supplied by the keyword CORIOLIS COEFFICIENT This must be calculated in accordance with the latitude λ by the formula:

FCOR = 2 ω sin(λ) ω being the angular velocity of the Earth, equal to 7.27 x 10-5 rad/s. The components of the Coriolis force are thus:

FU = FCOR x V and FV = -FCOR x U

In the case of very large domains such as portions of oceans, it is necessary to carry out a simulation with spherical coordinates, in which case the Coriolis coefficient is adjusted automatically at each point of the domain. In this case, it is necessary to indicate the angle between the geographic north and the Y-axis of the model. This information is supplied by the keyword NORTH. This gives the angle (in degrees) between the north and the Y-axis, expressed positively in a trigonometric direction (the default value of the keyword is zero). TELEMAC-2D also offers the possibility of defining the water density (keyword WATER DENSITY; the default value is 1020 kg/m3, i.e. a value corresponding to a moderately saline sea water) and gravity acceleration (keyword GRAVITY ACCELERATION fixed by default at 9.81 m/ s2).

4.8 Numerical parameter definition General parameter definition First, it is necessary to specify the type of equation to be solved. The choice is made by using the EQUATION keyword, which can take the following values:

- SAINT-VENANT FE (default value) - SAINT-VENANT FV - BOUSSINESQ

The first option involves solving the Saint-Venant equations using the finite-element method. This is the "traditional" use of TELEMAC-2D. The second option involves solving the Saint-Venant equations using the finite-volume method. In this case, the algorithm is explicit and means that the Courant number must be limited to 1. The variable time step option is then automatically used. TELEMAC-2D then adjusts the calculation time step so as to satisfy this Courant number criterion. However, it should be noted that this leads to irregular sampling from the graphic printout file and control listing. Lastly, it should be noted that all the options available when solving the Saint-Venant equations using the finite-element method are not necessarily available here.



The BOUSSINESQ option means that the equations are solved by the Boussinesq method. During computation, TELEMAC-2D solves different steps using, if necessary, the fractional step method (the advection equations and propagation-diffusion equations may be solved in two successive stages handled by different numerical schemes). The user can activate or deactivate certain of these steps. Whether or not the advection terms are taken into account is determined by the logical keyword ADVECTION (default value YES). However, even if this keyword is positioned at YES, it is possible to deactivate certain advection terms using the following logical keywords:

- ADVECTION OF H to take into account the advection of depth,

- ADVECTION OF U AND V for the advection of velocity-components,

- ADVECTION OF K AND EPSILON: for the advection of turbulent energy and turbulent dissipation,

- ADVECTION OF TRACER: for the advection of a tracer.

The phenomena of propagation will or will not be taken into account depending on the value of the keyword PROPAGATION (default value YES). As propagation and diffusion are processed in the same step, deactivating propagation will automatically entail deactivating diffusion. However, if the propagation-diffusion step is activated, the user may still decide whether or not to take into account velocity diffusion by setting the logical keyword DIFFUSION OF VELOCITY.

The Numerical Schemes In the present version of TELEMAC-2D, only the depth-velocity option can be used when solving the propagation step. The main choice concerns the scheme used for solving the advection step. To do this, the user must update the keyword TYPE OF ADVECTIONThis keyword is a table of four integers that are related successively to the scheme used for advection of the velocity (U and V), depth (H), tracer and turbulent value (k and epsilon). If the model does not include any tracer or turbulence model, the user may simply give the first two values. Each integer may have a value between 1 and 6 corresponding to the following possibilities: 1: Method of characteristics. 2: Centred semi implicit scheme + SUPG.

5: Conservative scheme + SUPG. 6: PSI scheme

Solving the Linear System Type OF PROCESSING When processing the linear system, it is possible to replace the original equations by a generalised wave equation obtained by eliminating the velocity from the continuity equation using a value obtained from the momentum equation. This technique increases calculation speed but has the disadvantage of smoothing the results.



Solver During certain steps, the solver used for solving the systems of equations may be selected by means of the following keywords:

- SOLVER: for the hydrodynamic propagation step.

- SOLVER FOR TRACER DIFFUSION: for the tracer diffusion step. - SOLVER FOR K-EPSILON MODEL for solving the turbulence model

system. Each of these keywords may have a value of between 1 and 7. These values correspond to the following possibilities, and are all related to the conjugate gradient method:

1: Conjugate gradient method. 2: Conjugate residual method.

3: Conjugate gradient on normal equation method. 4: Minimum error method. 5: Squared conjugate gradient method.

6: BICGSTAB (stabilised biconjugate gradient) method. 7: GMRES (Generalised Minimum RESidual) method.

Accuracy The linearized system is solved by an iterative method. It is therefore necessary to determine the accuracy that is to be achieved during the solving process and the maximum number of iterations permissible, to prevent the computation from entering unending loops if the required accuracy is not achieved. Either the process has converged before reaching the maximum permissible number of iterations, and in this case TELEMAC-2D provides the number of iterations actually run and the accuracy achieved. Or the process has not converged quickly enough. TELEMAC-2D then displays the message “MAXIMUM NUMBER OF ITERATIONS REACHED” and the accuracy actually achieved. In certain cases, and if the number of iterations is already positioned at a high value (e.g. more than 120), the convergence may still be improved by decreasing the time step or by modifying the mesh.

Continuity correction Residual mass errors (of the order of a few percent) may appear when using boundary conditions with imposed depth (case of a river downstream). Indeed the continuity equation is not solved for these points and is replaced by the equation depth = imposed value. Therefore, the resultant discharge is not properly computed and leads to error. The keyword CONTINUITY CORRECTION helps in correcting the velocity at these points so that the overall continuity is verified. This correction has enabled the error to be divided by as much as 1000. This correction is quite time-consuming and should be used only if the outlet discharge needs to be known precisely (in the case of calibration for example).



Preconditioning When solving a system of equations by a conjugate gradient method, convergence can often be hastened by means of preconditioning. TELEMAC-2D offers several possibilities for preconditioning : 0: No preconditioning.

2: Diagonal preconditioning (default value). 3: Block diagonal preconditioning

5: Diagonal preconditioning with absolute value. 7: Crout preconditioning per element. 11: Gauss-Seidel EBE preconditioning.

Courant number management During a model simulation, the Courant number value (number of grid cells crossed by a water particle during a time step) considerably influences the quality of the results. Irrespective of numerical schemes with a stability condition on the Courant number, experience shows that result quality decreases if the Courant number is above 7 or 8. Yet it is not so easy to estimate the value of the Courant number - especially in sea models with a large tidal range. To help, TELEMAC-2D allows the user to check the Courant number during computation: the software automatically executes intermediate time steps so that the Courant number keeps below a given value. It should be stressed that when a variable time step is used, sampling from the results file and control listing is no longer regular in time, as it depends directly on the time step value.

Tidal flats TELEMAC-2D offers several processing options for tidal flat areas. First of all, if the user is sure that the model will contain no tidal flats throughout the simulation, these may be deactivated by assigning NO to the keyword TIDAL FLATS (the default value is YES). This may mean that computational time can be saved. Tidal flats can be processed in three different ways:

- In the first case, the tidal flats are detected and the free surface gradient is corrected. Areas of negative water depth are smoothed (as are tracers if any exist) in order to prevent spurious solutions from appearing.

- In the second case, the tidal flat areas are removed from the computation. Exposed elements still form part of the mesh but any contributions they make to the computations are cancelled by a so-called "masking" table. The data structure and the computations are thus formally the same to within the value of the masking coefficient. However, in this case, mass-conservation may be slightly altered. As with element masking, this option is only available if a mesh node does not belong to more than 10 elements.

- In the third case, processing is done in the same way as in the first case, but a porosity term is added to half-dry elements. Consequently,



the quantity of water is changed and is no longer equal to the depth integral over the entire domain but to the depth integral multiplied by the porosity. The user can modify the porosity value determined by the processing in the CORPOR subroutine.

The type of processing is chosen with the keyword OPTION FOR THE TREATMENT OF TIDAL FLATS which may have a value of 1 or 2, the default value being 1.

In certain cases, it may be advisable to limit the lower water depth value. The most common case involves eliminating negative values of H. To do this the user assigns the value YES to the keyword H CLIPPING (default value NO). The keyword MINIMUM VALUE OF H which has a default value of 0, is used to fix the threshold below which clipping is performed. However, it should be borne in mind that this latter option leads to an increase in the mass of water as it eliminates negative water depths.

4.9 Other parameters Matrix Storage TELEMAC-2D includes 2 different methods of matrix storage: a classical method and assembled elementary storage method. 1: classical method (default value) 3: assembled elementary storage method.

Matrix-vector Two matrix-vector product methods are included in TELEMAC-2D: a classical method for the multiplication of a vector by a non-assembled matrix and a new method of frontal multiplication with an assembled matrix: 1: multiplication of a vector by a non-assembled matrix (default value)

2: frontal multiplication with an assembled matrix

4.10 Tracer Transport With TELEMAC-2D it is possible to take into account the transport of a non-buoyant tracer (i.e. one whose presence has no effect on the hydrodynamics), which may or may not be diffused.

4.11 Drogues and Lagrangian Drifts DROGUE DISPLACEMENTS During a hydrodynamic simulation, TELEMAC-2D offers the possibility of monitoring the tracks followed by certain particles (drogues) introduced into the fluid from outflow points. The result is produced in the form of a Selafin-format file containing the various positions of the drogues in the form of a degenerated mesh.



LAGRANGIAN DRIFTS Computing Lagrangian drifts involves computing the displacement of all mesh points between two given instants. Typically, these two instants may be two consecutive high tides. To run such a computation, it is necessary to program the steering file and FORTRAN file.

4.12 Weirs and culverts Weirs Weirs are considered as linewise singularities. The number of weirs is specified by the keyword NUMBER OF WEIRS (default value 0). Information about weirs is given in the FORMATTED DATA FILE 1. If there are also culverts, information about them should be placed after.

A weir must be prepared in the mesh and consists of two boundary lines which are actually linked by the weir. In principle, these boundaries should be sufficiently far apart, upstream and downstream of the weir. The upstream and downstream boundary points should correspond 1 to 1, and the distance between two points should be the same on both sides.

Culverts Culverts or siphons are described as couples of points between which flow may occur, as a function of the respective water level at these points. Beforehand, each culvert inflow and outflow has to be described as a source point with the usual keywords.

4.13 Other configurations Modification OF BOTTOM TOPOGRAPHY (CORFON) TELEMAC-2D offers the possibility of modifying the bottom topography at the start of a computation using the CORFON subroutine. This is called up once at the start of the computation and enables the value of variable ZF to be modified at each point of the mesh. To do this, a number of variables such as the point coordinates, the element surface value, table of connectivities, etc, are made available to the user.

Modifying COORDINATES (CORRXY) TELEMAC-2D also offers the possibility of modifying the mesh point coordinates at the start of a computation. This means, for example, that it is possible to change the scale (from that of a reduced-scale model to that of the real object), rotate or shift the object.

SPHERICAL COORDINATES (LATITU) If a simulation is being performed over a large domain, TELEMAC-2D offers the possibility of running the computation with spherical coordinates. In its present version, TELEMAC-2D assumes that the mesh coordinates are given in accordance with Mercator’s projection.

Adding new variables (NOMVAR-TELEMAC2D and PRERES_TELEMAC2D) A standard feature of TELEMAC-2D is the storage of certain computed variables. In certain cases, the user may wish to compute other variables and insert them in the results file (the number of variables is currently limited to four). TELEMAC-2D has a numbering system in which, for example,



the array containing the Froude number has the number 7. The new variables created by the user may have the numbers 23, 24, 25 and 26.

Coupling The principle of coupling two (or in theory more) simulation modules involves running the two calculations simultaneously and exchanging the various results at each time step. For example, the following principle is used to link a hydrodynamic module and sedimentological module:

- The two codes perform the calculation at the initial instant with the same information (in particular the mesh and bottom topography).

- The hydrodynamic code runs a time step and calculates the depth of water and velocity components. It provides this information to the sedimentological code.

- The sedimentological code uses this information to run the solid transport calculation over a time step and thus calculates a change in the bottom.

- The new bottom value is then taken into account by the hydrodynamic module at the next time step, and so on.

Fourier Analysis TELEMAC-2D allows the user to analyse free surface variations in order to determine the phase and amplitude of one or more waves. This can only be done if the mean level is zero. Amplitudes and phases are supplied for each point and for each period.



5 SUBIEF-2D: WATER QUALITY SIMULATION 5.1 Introduction :

SUBIEF code is used to study the transport of one or several tracers in a 2-dimensional free surface flow. These tracers can be diluted or in suspension in the water. In the latter case, SUBIEF can calculate their settling on the bottom and their return to suspension through erosion. Tracers can be coupled; they can even stay without being displaced by the current but vary as a function of time. For each tracer, various physical phenomena can be selected: drift, diffusion, settling, erosion, couplings, source terms to be defined. SUBIEF has been designed based on TELEMAC-2D finite element structure. It is a bidimensional code; its variables are thus obtained by integration into each water head.

SUBIEF code equations are dissociated from hydrodynamics. Hydrodynamic calculations are carried out by TELEMAC-2D in a first stage. SUBIEF reads TELEMAC-2D results file to build the advective field used to solve one or two transport equations.

However, the compatibility between the hydrodynamic calculation and the transport calculation is essential. This is true in particular for the conservation of the tracer mass which is related to the water mass conservation. The quality of the results obtained with SUBIEF is highly dependent on the quality of the earlier hydrodynamic calculation, even if a simple passive tracer transport is modelled. And logically, a user should not expect a correct reproduction of the evolution of bottoms if the computation of the field of currents is of poor quality.

5.2 Reminder of equations solved: SUBIEF solves the following transport, deposition and erosion equation:

Žc Žt

+ u . grad c = div( K . grad c ) + Qe - Qdh

+ ∑points r

sources (cs - c) QL(r)

h ψ r d Ω

+ S

where : c : tracer concentration in suspension (g/l)

K : dispersion coefficient (m2/s)

u : flow linear velocity (m/s) h : water head (m)

Qe : erosion flux (kg m-2s-1)

Qd : deposition flux (kg m-2s-1) cs : concentration of tracer at source point r (g/l) QL : source r liquid flow rate (m3/s)

S : any source terms to be defined (g/l/s) Ψr : basic function (finite elements) at source point r



Deposition flux and erosion flux are calculated with Krone and Partheniades formulae respectively:

Qd = Wc c 1 - (u*

ud*)2

and Qe = M (u*

ue*)2 - 1

where Wc : settling velocity (m/s) M : Parthéniades constant

ud* and ue

* : critical settling and erosion velocities u* : friction velocity at the bottom.

Bottom evolution (i.e., bottom level variation) is then equal to:

E = Qd - Qe

Csf DT

at each time step (m)

Csf being the concentration of the settled layer. (kg/m3)

S is a source term, a priori null; but which can be defined by user.



ZR

ZF

BOTTOMS WHICH CANNOT BE ERODED

BOTTOMS WHICH CAN BE ERODED Csf

Z free surface

h Uc

QdQe

SUBIEF CODE BLOCK DIAGRAM

S : exchanges

The tracer transport equation can be solved several times inside a given time step. One can thus model several tracers. For each of them, it is possible to choose whether advection or dispersion processes have to be taken into account. The "S" term can for example be a function of other tracers concentrations. It can also depend on some parameters previously defined by the user. By these means, water quality models can be built.



5.3 Water Quality in SUBIEF : Generalities:

A first step in a SUBIEF computation consists in choosing the variables to be transported by the flow. One then has to determine which other phenomena -but transport- may affect these variables (source terms "S" for each equation). Finally, it is necessary to get a proper mathematical modeling for these phenomena. The whole final informations can be called "Water Quality Model".

For a SUBIEF user, a water quality model holds entirely in a single text file known as a "Water Quality File". This file is built such that the informations it contains (names of the variables, equations,...) can be easily read and modified. It makes it possible for a user to build rapidly its own water quality models. However, this file cannot be directly "understood" by the SUBIEF software. Each water quality file (or model) is thus associated to a "Water Quality Directory" that holds in fact the same informations that the associated water quality file, but written in a way that SUBIEF can manage. A shellscript called wq2subief allows to generate automatically the water quality directory starting from the water quality file. To summarize :

1 water quality model = 1 water quality file = 1 water quality directory

Water Quality File

Water Quality Directory

SUBIEFTELEMAC-2D hydrodynamics

SUBIEF results

wq2subief

Other SUBIEF input files

SUBIEF organization



The Water Quality file DEFINITIONS

A Water Quality model is to be defined in a "Water Quality file". Four different classes of objects may be used to do so:

- State variables: These variables can be chemical components, tracers, suspended sediments.One is most often interested in the depth- averaged concentration of each variable in each point of the mesh. A variable V will be a state variable if SUBIEF has to compute its variation according to a "dV/dt =..." equation.

- Computed variables: These variables are computed in each point of the mesh using the values of other variables. It is then possible to write these variables into the SUBIEF results file in order to see them into RUBENS. In opposition with State Variables, Computed variables are calculated using a "V = ..." equation.

- Parameters: These are some constants used to parameter the equations of the model. There are two kinds of parameters :

- Parameters which are input data for the model, whose values are likely to be changed by the user during the study. Such parameters are called external parameters. They define a Water Quality Model Dictionnary. The user can change the external parameters values directly from a Water Quality Steering File.

- Parameters which appear in the equations of the model just as computation intermediates, necessary to make these equations readable. These are the internal parameters.

- Forcing functions : They play the same role than external parameters, but are defined on each point of the mesh and may be variable in time.



5.4 The files used by SUBIEF

steering file

hydrodynamic file

boundary conditions file

fortran file

Water Quality steering file

USERS FILE

damocles

imposed concentrations file

forcing functions file

source points file

initial conditions file

LECDON.h

CHIMIE.h

Water Quality Model Dictionnary

Water Quality File

w q 2 s u b i e f

inclusion

tasks performed by the SUBIEF launcher

tasks performed by wq2subief

THE FILES USED BY SUBIEF

Water Quality Directory

model.wq

model.SUB

LIST OF THE FILES : A SUBIEF project is made of files which will be used or created by the software. Some of them are absolutely needed (+) while others will appear only in specific situations (-). Some of these files (T2D) come directly from the hydrodynamics computation performed previously with TELEMAC-2D.



There are 17 files :

Water Quality Model Directory (+) input File lecdon.h (+) input File chimie.h (+) input File dicowq (+) input

Steering File (+) input Water Quality Steering File (+) input

Boundary conditions file (+) input (T2D) Fortran file (+) input

Geometry file (+) input (T2D) Results file (+) output

Listing file (-) output Hydrodynamics file (+) input (T2D)

Previous sedimentological file (-) input

Imposed concentrations at boundaries file (-) input Initial conditions file (-) input Source points file (-) input

Forcing functions file (-) input

DESCRIPTION OF THE VARIOUS FILES : THE STEERING FILE :

This ASCII file is the main control file of the program. It concerns all the computation parameters, excluding the parameters of the Water Quality Model. It contains :

- the relative paths of the various files to use in the computation,

- some numerical parameters (SUBIEF release, time step, advection scheme, ...).

- some physical parameters linked with hydrodynamics (friction coefficient,...)

The steering file consists of a set of keywords to which values are assigned, for instance: The order of these key-words in the file does not matter. Often, the parameter file is arbitrarily separated in two zones (it is only a practical layout). One half is dedicated to the



initiating procedure and essentially includes the names of the files used, which are described in this section. The other is used to define the set of parameters and SUBIEF physical or numerical options. If a key-word is not listed in the STEERING FILE, a preset value will be attributed to it by default.

THE WATER QUALITY STEERING FILE : This file is used to set values to the water quality model external parameters. These parameters are defined in the water quality dictionary file dicowq located in the model.SUB directory. The water quality dictionary file is thus given for each water quality model. The rules for writing keywords in the Water Quality steering file are the same than in the steering file.

THE WATER QUALITY DIRECTORY : This directory is generated by wq2subief from the water quality file model.wq. It has to contain a minima the dicowq, lecdon.h, and chimie.h files.

THE BOUNDARY CONDITIONS FILE : In this ASCII file, the user can specify, for each boundary point of the mesh, the type of physical condition which the tracer must meet. In SUBIEF the concept is to have as few files distinct from the files used by TELEMAC as possible. For this reason, both codes use the same file for boundary conditions. This file is automatically filled by STBTEL interface but it can also be built or modified via a text editor. Each line in this file is dedicated to one boundary point. The boundary points are numbered according to their row in the file; the number indicates the domain contour in the trigonometrical direction first, then the islands clockwise. For each boundary point, you can read in the boundary conditions file, the following thirteen variables laid out in 13 columns.

THE FORTRAN FILE : This is a text file in FORTRAN consisting of a set of subroutines belonging to the FORTRAN libraries used by SUBIEF and accessible to the user. It contains the FORTRAN subroutines that the user wants to modify for the specific needs of the case under consideration.

The FORTRAN FILE has to contain at least the subroutines LECDON and CHIMIE. LECDON and CHIMIE are concerned with FORTRAN inclusions as SUBIEF is started (lecdon.h and chimie.h files inclusions)

THE GEOMETRY FILE : This is a binary file containing the information related to the mesh and, in most cases, the bottoms interpolated on it. This file is generated by STBTEL interface. The mesh can be visualized by means of RUBENS graphics postprocessor.



THE RESULTS FILE : This binary file is created by SUBIEF automatically. It contains information about the mesh, then the values taken on by variables for a number of time steps in computation. This file can be visualized via RUBENS.

THE LISTING FILE This ASCII file provides information about the computation (convergence, results).

THE HYDRODYNAMIC FILE This is a TELEMAC-2D result file. It contains information about the mesh, then the values taken on by the water head h and the two horizontal components of the current u and v for a number of time steps. The time interval which separates two hydrodynamic records (h, u, v) is the graphic printout period which had been specified during the calculation with TELEMAC-2D. The reading of this file by SUBIEF will be different depending on whether the hydrodynamics of the case of interest to the user is steady state or not. Consequently, there are several specific keywords for each of the two options.

THE PREVIOUS SEDIMENTOLOGICAL FILE: This is a SUBIEF results file (name inherited from SUBIEF’s first ages). It contains the records of variables specified as graphics output during a computation with SUBIEF. The role of this file is to allow the user to perform a sequence of calculations. In such a case, SUBIEF reads the last record in the PREVIOUS SEDIMENTOLOGICAL FILE and extracts the current state variables (concentrations), the bottom evolution ... This data then constitutes the initial status of the new calculation.

THE IMPOSED CONCENTRATION FILE This file is built to set the concentrations of state variables on the boundaries where they are imposed (frontiers with entering velocities and LICBOR= 5). These concentrations can be time dependent.

THE INITIAL CONDITIONS FILE: In this file, the user can define initial concentrations for the state variables as well as areas where these concentrations have to be imposed at t=0 (0th time step).

THE FORCING FUNCTIONS FILE This file allows to set the forcing functions values on some previously defined areas of the computational domain. The forcing functions are defined within the water quality file They can be time dependent.



THE SOURCE POINTS FILE This file is used to set the characteristics of the punctual outfalls inside the domain (i.e excluding boundaries). Up to 100 outfalls can be defined by the means of :

- their location,

- their water discharge (m3/s), - the concentrations at source point of the released fluid components.



6 RUBENS: GRAPHICAL POST PROCESSOR RUBENS is used for exploiting the results of one- and two-dimensional numerical simulations, in the form of analyses or high-quality printed documents. RUBENS is a part of the TELEMAC modelling system. It is based on the use of Ilog/Views libraries; RUBENS is particularly user-friendly and easy to use. It is one of the most versatile and powerful post-processing programs.

6.1 Analysis of results

RUBENS offers the user a wide range of graphs for analysing the results of simulations (and for comparing with measurements if necessary).

- Isovalue curves and coloured areas

- Vector fields

- Current lines and trajectories

- Space- and time-dependent profiles

- 2D profiles with perspective

- 3D profiles

RUBENS contains many features giving the user every opportunity to exploit and validate the results of a simulation.

- Probe

- Zoom (with the mouse or numerically)

- Calculation of new variables

- Balance (spatial integration)

- Calculation of volumes

- Correlation

- Superimposition of graphs

The different functions are accessed via scrolling menus. There are also many keyboard short-cuts enabling experienced users to save considerable time.

Whenever a modelling study is being carried out, it is necessary to be able to produce high-quality documents for presenting the results.



6.2 Presentation documents

In addition to results analysis graphs, RUBENS provides many texts and graphics options:

- Text

- Horizontal/vertical line

- Random line

- Arrow

- Frame (empty or full)

- Random contour (broken line)

RUBENS can also generate printable Postscript and HPGL files and, depending on configuration, exchange files (GIF, XPM and other formats).

Lastly, batch processing offers the possibility of automatically generating series of images for creating animated presentations.

Some illustrations are given in the next paragraph “Smart case studies”. Some technical detailed information about this module is also presented in the RUBENS manual.



7 SMART CASE STUDIES 7.1 Construction, calibration, validation and exploitation In the life of a mathematical model there are 4 main steps:

- Construction step: compilation of the data (bathymetry, initial conditions, boundary conditions), generation of the grid in order to get a first hydrodynamic calculation,

- Calibration step: compilation of various information needed to the calibration of the hydrodynamic model (water level, velocity) in order to compare the results from the mathematical model with the observed data,

- Validation step: when the calibration step is ready, a new calculation is done with a set of new data (for instance new wind conditions) and a new comparison is done between the model results and the observed data in order to validate the mathematical model.

For each step different sets of data is needed. These data are presented in the next paragraph.

Then, when these first 3 steps have been done, the model is ready for exploitation and scenario simulations.

7.2 Data requirement The different steps and set of data:

- Compilation of the bathymetrical data and analysis of the coherence and validity of this information. For the coastal zone model, the bathymetrical information should be very detailed near the coast or around some specific point of interest as treatment plant, river mouth, etc. in order to simulate as good as possible the polluted plumes near the beaches or other tourist spots. If the hydrodynamic in the river is important for the scenarii, information on the river cross sections is also needed. If the aim of the model is only the pollution from the river and its impact on the coastal zone, or the impact of the river discharge in the hydrodynamic of the coast, cross sections are not necessary, but we will need to collect information about the river discharges and/or pollutant concentrations.

- Compilation of data for the initial conditions (wind series, wave periods, data on the river discharge), and analyse of the validity of these data.

- Compilation of water quality data: physical and chemical characteristic of the pollutant (name of the pollutant, type of pollutant, half time life, punctual concentration at the specific point as chemical plant -time series, concentration spatially distributed in the coastal zone area - 2D map for initial model condition, concentration at the mouth of the river - time series), pollutant discharges (at the river mouth, at the plant, etc - time series information).



- Compilation of various information needed to the calibration of the hydrodynamic model (water level, velocity: intensity and direction).

- Compilation of various information needed to the calibration of the water quality model (plume extension for pollutant, punctual concentration evolution)

-

7.3 Description of the five case studies

Turkey : Izmir Bay and Gediz river Description of the coastal zone The Bay of Izmir is one of the largest bays of the Turkish Aegean coast. It is roughly “L” shaped that its length is approximately 45 km, and its width at the mouth section is about 24 km. From the standpoint of its topographical and hydrographical characteristics, this L-shaped bay consists of three sections: the Inner Bay, the Middle Bay, and the Outer Bay. The Gediz River is discharging to the outer bay. The Gediz River was diverted to the outer bay in the late 19th Century, in order to prevent the inner İzmir Bay from silting up. The Gediz River is formed from the confluence of waters coming from the Murat and Şaphane mountains in central western Anatolia.

Pollution sources. The inner Bay of Izmir is surrounded by the area of the Metropolitan Municipality of Izmir (MMI) which has the approximate population of 2,3 million (2000 census), and has been polluted by uncontrolled domestic and industrial waste waters until recent times. In order to control the pollution of Izmir Bay, Izmir Sewage Project was prepared and applied in 2002. Recently, the bay has started to recover itself. The sewage project consists of two parts. The first one collects wastewaters of the northern part of the Izmir city, and after the treatment, discharges to the middle bay. The second part collects of the wastewaters of the southern part of the city and discharges to middle bay also. The river brings the pollution of the human activities such as agriculture, industry and household in the Gediz river basin. The major pollution loads comes from agricultural activities.



Major problems and issues Before the new sewage project, the environmental situation of Izmir, particularly that of its Bay area, had caused that the natural systems are no longer able to accommodate the pressures of human activities. The development had brought about a series of conflicts of interests over the use of resources which have not only resulted in a deteriorated state of natural systems but also in a diminished capacity of the systems to produce enough high-quality goods and services that the area had traditionally been providing (fisheries, sailing, tourism, agriculture, etc.). Recently, the positive effects of the new sewage project have been screened. The effect of the Gediz river discharges has not been identified technically yet. Characteristics of the situation found may be summarized as follows:

- Urban development, reflecting high population growth, is continuing around the bay area and consuming the scarcest resources – the land. Although the treatment, urban waste waters and stormwaters are one of the major sources of pollution of the bay.

- Loss of cultivated land to residential purposes on the one hand, and increasing demands for agricultural produce on the other, have reduced the nature conservation areas, decreased the level of flood protection, and increased soil erosion.



- Discharges of domestic and industrial waters, urban and agricultural run-off, sediments and contaminated waters from rivers (including Gediz) and streams have had a cumulative adverse impact on the water quality and natural characteristics of the Inner Bay, resulting in eutrophication.

- Many problems relative to the environmental degradation and pollution of the Izmir area result from institutional drawbacks, such us: insufficient cross-sectorial (horizontal) and institutional (vertical) co-ordination and integration of activities at various institutional levels; divergence in policy objectives pursued by various authorities; lack of funds for environmental purposes including the development of a consistent ecological monitoring; absence of an adequate system of integrated planning and management.

TELEMAC studies objectives

By using the Telemac capabilities and available data, the current pollution distribution in the whole bay will be investigate and comparative analyses of the current and past situation will be established. The expected results will show the performance of the treatment plans in the future. Beside that, the modelling results will indicate that how much pollution load comes from the Gediz River to the inner bay, and what is the permissible amount of pollution from the Gediz River in order to constitute sustainable coastal water quality.

Graphical TELEMAC model printouts :

Egypt : Abu Kir Bay and Idku Lake Description of the coastal zone Semi-enclosed bay with an outlet from the Idku Lake.



Pollution sources The main pollution comes from:

- Industry - Domestic waste waters

- Agriculture

Major problems and issues (Definition still in progress)

TELEMAC studies objectives The TELEMAC studies objectives are:

- Computation of the current fields in the whole bay generated by the wind effects,

- To calculate the water exchange between the sea and the lake,



- To represent the influence of numerous discharge sources on the lake hydrodynamics,

- To represent the pollution transfer from the lake to the sea.

Graphical TELEMAC model printouts : (No available yet)

Lebanon : Abu Ali Bay Description of the coastal zone Open coastline with Abu-Ali river outlet and waste dump sewage.

Pollution sources - Industrial flows - Waste water

- Agrochemical pollution

Major problems and issues The pollution transfer of chemical pollutant from industrial plants into the sea.

TELEMAC studies objectives - To represent the current fields generated by the wind.

- To compute the pollutant transport by currents in the studied area.






Jordan : Gulf of Aqaba Description of the coastal zone Narrow gulf with industrial discharge.



Pollution sources - Industrial water reuse, - Industrial reject,

- Phosphate dust, - Coastal tourism activities.

Major problems and issues - Pollution from power plants : sulphur release, - Industrial rejects

- Effect on the submarine fauna and on tourism activities.

TELEMAC studies objectives - To compute the current fields in the whole gulf generated by the tide

and by the wind,



- Underline the influence of these both factors on the local hydrodynamic,

- Compute the pollutant evolution in the Gulf.








Tunisia : Hammamet Description of the coastal zone Open coastline with outlet from individual hostel and oueds discharge points.

Pollution sources - Domestic and urban flows from tourism activities , - Pollution coming from oueds

Major problems and issues - Flooding risk from oueds, - Incidence of floods on the local marine hydrodynamic,

- Domestic and urban pollution from marine emissaries into the sea.

TELEMAC studies objectives - Wastewater discharges in oueds sections and their transfer to the sea. - Wastewater pollution effects by marine emissaries.

Graphical TELEMAC model printouts : (No yet available)



8 REFERENCES TELEMAC-2D J.-M. HERVOUET Comparison of experimental data and laser measurements with the computational results of TELEMAC code (shallow water equations). Communication au congrès "Hydrocomp '89" à Dubrovnik. 13-16 Juin 1989. O. DAUBERT , J.-M. HERVOUET and A. JAMI Description of some numerical tools for solving incompressible turbulent and free surface flows. International Journal for Numerical Methods in Engineering. Vol. 27,3-20 (1989). N. GOUTAL Finite element solution for the transcritical shallow-water equation. Mathematical Methods in the Applied Sciences. Vol.11,503-524 (1989). J.-M. HERVOUET Vectorisation et simplification des algorithmes en éléments finis Bulletin de la Direction des Etudes et Recherches. N° 1. Mars 1991 J.-M. HERVOUET, P. PECHON Modélisation numérique des écoulements à surface libre. L'état de l'art au Laboratoire National d'Hydraulique (LNH) de l'EDF à Chatou. La Houille Blanche n°2 . 1991 G. BENOIST, J.-M. HERVOUET, G. LABADIE L'expérience d'EDF en matière de calcul des ondes de submersion. Colloque International sur la simulation des ondes de submersion. Montréal 8-11 Avril 1991 J.-C. GALLAND, N. GOUTAL, J.-M. HERVOUET A new numerical model for solving shallow water equations. Advances in Water Resources. Vol. 14 n°3 June 1991 pp.138-148. G. LABADIE, S. PERON, J.-M. HERVOUET Study of head losses in a confluence of rivers with a scale model and a numerical model solving shallow water equations. Refined flows modelling. XXIV IAHR Congress. Madrid 9-13 Septembre 1991. J.-M. HERVOUET TELEMAC, a fully vectorised finite element sofware for shallow water equations. Computer Methods and Water Resources. Rabat, Morocco.7-11 Oct. 1991. J.-M. HERVOUET , G. LABADIE, F. LEPEINTRE Progress in the development of numerical tools for environmental studies in the Laboratoire National d'Hydraulique. Invited paper in the International Symposium on Environmental Hydraulics. Hong-Kong December 16-18 1991. J.-C. GALLAND, J.-M. JANIN Modélisation numérique du cycle de marées sur le plateau continental Nord-Ouest européen. Communication aux Journées Nationales sur le génie cotier et le génie civil. Nantes



J.-M. HERVOUET Element by Element methods for solving shallow water equations with F.E.M. IX International Conference on Computational Methods in Water Resources. Denver, Colorado.USA 9-12 Juin 1992. J.-M. HERVOUET Solving shallow water equations with rapid flows and tidal flats. Hydrosoft 92.Valence.Espagne. 21-23 Juillet 1992. J.-M. JANIN, J.-C. GALLAND Numerical modelling of tidal currents along the west European continental shelf in order to predict the movements of polluted matters. 2nd International Conference on Hydraulic and environment modelling of coastal, estuarine and river waters. University of Bradford. 22-24 Septembre 1992. J.-M. HERVOUET Validating the numerical simulation of dam-breaks and floods. First International Conference on Hydro-Science and Engineering. 7-11 Juin 1993. Washington U.S.A. J.-M. JANIN, F. DUMAS Modélisation fine des dérives Lagrangiennes en Manche par un code aux éléments finis. Communication aux IIIièmes journées Nationales du Génie Côtier-Génie civil.. Sète. 2-4 Mars 1994 J.-M. HERVOUET Finite Element algorithms for modelling flood propagation Specialty Conference on Modelling of Flood Propagation Over Initially Dry Areas. Milan. Italie. 29-30 Juin 1994. J.-M. HERVOUET, J.-M. JANIN, C. MOULIN Preconditioning and solving linear systems for the computation of free surface flows. X International Conference on Computational Methods in Water Resources. Heidelberg. Allemagne. 19-22 Juillet 1994. J.-M. HERVOUET Computation of 2D free surface flows. The state of the art in the TELEMAC system. First International Conference on Hydroinformatics. Delft. Hollande. 19-23 Septembre 1994. J.-M. HERVOUET, C. MOULIN Modèles mathématiques aux éléments finis pour l'analyse des crues et des inondations. 23ièmes journées de l'hydraulique. Nîmes. 14-16 Septembre 1994. M.G. ANDERSON, P.D. BATES, J.-M. HERVOUET Computation of a flood event using a two dimensional finite element model and its comparison to field data. Specialty Conference on Modelling of Flood Propagation Over Initially Dry Areas. Milan. Italie. 29-30 Juin 1994. M.G. ANDERSON, P.D. BATES, J.-M. HERVOUET An initial comparison of two 2-dimensional finite element codes for river flood simulation. Proceedings of the Institute of Civil Engineers: Water, Maritime and energy.112.238-248 M.G. ANDERSON, P.D. BATES, J.-M. HERVOUET, J.-C. HAWKES



Investigating the behaviour of two-dimensional finite element models of compound channel flow. Earth Surface Processes and Landforms. (accepted, in press) J.-M. HERVOUET, L. VAN HAREN Recent advances in numerical methods for fluid flow. In M.G. ANDERSON, D.E. Walling and P.D. Bates (eds.) Floodplain processes. John Wiley, Chichester. (in press) J.-M. JANIN Numerical modelling of free surface flows applied to environmental problems. 3rd International Workshop on Experimentation, Modelization, Computaion in Flow, Turbulence and Combustion - Tashkent, Uzbekistan - Avril 95. J.-M. JANIN, F. DUMAS, T. LEVAILLANT Modélisation fine des dérives lagrangiennes en Manche par un code aux éléments finis. Colloque sur la Dynamique Océanique Côtière - Paris - Juin 95. J.-M. HERVOUET, J.-M. JANIN, E. BARROS Refined flow modelling in coastal areas. Proceedings of the "COASTAL 95" second international conference. Cancun, MEXICO. 6-8 September 95. C. MOULIN, J.-M. HERVOUET, J.-M. JANIN Advection/Diffusion equations using finite element methods in the TELEMAC system. Finite Elements in Fluids. New trends and applications. Venise. 15-21 Oct. 1995. J.-M. JANIN, F. MARCOS Qualité des eaux du Golfe du Morbihan - Utilisation d'un modèle hydrodynamique. IVèmes journées nationales Génie Côtier Génie Civil - Dinard - Avril 96. J.-M. HERVOUET Recent Advances in the TELEMAC System Proceedings of the "APCOM 96" Third Asian Pacific conference. Seoul. Corée du Sud. 16-18 September 96. T.D. FAURE Unsteady flow modelling on a beach using TELEMAC-2D. 1995 annual conference of the canadian society for civil engineering. June 1-3,1995, Ottawa, Ontario. J.-M. HERVOUET, J.-M. JANIN, F. MARCOS Numerical modelling of free surface flows. Devising strategies for parallelism. Computer Modelling of seas and Coastal Regions III. 23-25 June 1997. La Coruna. Spain J.-M. HERVOUET A numerical simulation of the Malpasset Dam-Break with 2D Saint-Venant equations. Proceedings of "Saint-Venant symposium" 28-29 August 1997. Marne la Vallée. France P.-D. BATES, G.B. SIGGERS, M.D. STEWART Physical model and internal validation of two dimensional finite element models for flood flow prediction. British Hydrological Society Symposium on Hydrology in a Changing Environment. Theme 4: Hydrology of Environmental Hazards. P.-D. BATES, J.-M. HERVOUET A new method for moving-boundary hydrodynamic problems in shallow water. Proc.R.Soc.Lond.A(1999).455,3107-3128



P.-D. BATES, M.D. STEWART, G.B. SIGGERS, C.N. SMITH, J.-M. HERVOUET, R.H.J. SELLIN Internal and external validation of a two-dimensional finite element code for river flood simulations. Proc.Instn.Civ.Engrs.Wat.Marit. & Energy, 1998, 130, Sept.,127-141. SUBIEF-2D C. MOULIN, E. BEN SLAMA The 2-D transport module SUBIEF : applications to sediment transport and water quality processes. Hydrological processes : special edition on high resolution flow modelling. 1997 J.-M. JANIN Numerical modelling of free surface flows applied to environmental problems. 3rd International Workshop on Experimentation, Modelization, Computaion in Flow, Turbulence and Combustion - Tashkent, Uzbekistan - Avril 95 J.-M. JANIN, F. MARCOS Qualité des eaux du Golfe du Morbihan - Utilisation d'un modèle hydrodynamique. IVèmes journées nationales Génie Côtier Génie Civil - Dinard - Avril 96 P.-L. LUCILLE Development of a hydrogeochemical model for radionuclides migration. Proceedings du 27ème congrès AIRH - San Francisco - Août 1997



ANNEXES



ANNEXE 1: HARDWARE AND SOFTWARE REQUIREMENTS (WINDOWS) Simulation modules: Hardware:

• 2GHz Pentium IV processor

• 128Mb RAM

Software:

• Windows NT4 or Windows 2000 or Windows XP

• Compaq Visual Fortran compiler (version6.5 or later)

Pre and Post-processors (MATISSE and RUBENS) Hardware:

• 600 MHz Pentium III processor

• 256 Mb RAM

Software:

• Windows NT4 or Windows 2000 or Windows XP

Disk Space The complete TELEMAC system necessitates 550 Mb of disk space.



ANNEXE 2: IMPLEMENTING THE CODES

TELEMAC tree structure

All of the TELEMAC System codes are located within one disk tree which has "systel90|" as a root. That tree structure is arranged as follows:

systel90 | | +---bin Script and utility files +---perl PERL TREE | Script and utility files | +---config Configuration/setup files +---docs Documentation files | +---install Code installation tools | +---damocles reads the steering file +---bief finite element library +---paravoid void version of parallel library + +---arshd Libraries for codes +---parallel parallel library based on pvm +---pvm Parallel Virtual Machine library +---protection Files with passwords | +---telemac2d +---telemac3d Directories +---artemis of +---cowadis the +---postel3d TELEMAC +---sisyphe System +---stbtel codes +---subief2d +---subief3d +---tomawac +---estel2d

All the file and directory names are typed in lower case in that TELEMAC tree structure (except, possibly, the pvm, perl and arshd directories).



Running a code

Control

Before running your code, make sure that there is no blank nor diacritical sign (é,à,ç,è) in your file names and in your paths.

Every code start-up command is given the code name. Thus, under both UNIX ands WINDOWS NT, the code is started up through the "name_of_code" command, as in the following example for TELEMAC 2D:

% telemac2d

That command activates the launcher of the TELEMAC2D code, which is a PERL script from the script directory ("systel90|bin"), which is given in the PATH during the installation.

Options The general starting syntax of a code in the TELEMAC SYSTEM is as follows:

% code [ -h ] [ -s ] [ -b ] [-d HH:MM ] [steering_file]

The following options are mentioned:

-h control syntax display

-s interactive execution with a screen display capture in a printout file

-b batch processing

-d batch processing beginning at the time HH:MM

steering_file data file name (damocles-formatted "case" file)

The default values are as follows:

• "cas" is the case file name being considered if " steering_file " is unspecified • the execution is interactive on the screen

Debug et profile modes:

In addition to the above options, the debug and profile execution modes can be used in the development, optimization or error trapping phase.

Debug : -D option provides for a more precise error traceability. The operation depends on the compiler and the debugger being used. The debugger can be selected with the variable RUN_DEBUG in the systel.ini configuration file. On a HP compiler with RUN_DEBUG="xdb ",



for example, one comes to a window with a command prompt. The usual commands are as follows :

file source.f : gives the debugger the Fortran source name. r : start the computation from the beginning. P TOTO : give the value of the TOTO variable.

c : proceed with the computation. b 5843 : put a stop on line 5843 db* : clear all the stops. /NBOR : reach the NBOR character string in the Fortran source.

q : quit

RUN_DEBUG="dde " gives another debugger which allows an easy navigation in the calling tree and points out the line causing an error.

Profile : -g option analysis of times spent in each subroutine. During an execution in the profile mode, the temporary file as created by the launcher is not deleted and a so-called gmon.out file (or a mon.out file in some machines) will be found in it. The so-called out4521.exe executable, for example, can also be found in the file. On Unix, the data of the profile mode will be got by typing in (after previously going to the temporary file) : gprof out4521.exe gmon.out (or prof in some computers).

Notes:

On UNIX, the "-s", "-b", "-d" options induce a "bufferization" of the display which is then produced in the form of a set of lines. When there is no user's Fortran file, the launcher invokes a pre-compiled executable. In such a case, no compiler is needed. It should be kept in mind, however, that some compilers have executables that only run with a "runtime" or with dynamic linking. The executable that was constructed upon when first invoked by the launcher is kept. If the user's Fortran file remains unchanged until a second call is made, no further compilation will take place. If any change occur in the meantime in the libraries, the change will be ignored; in case of any uncertainty, delete the so-called princi.exe executable if the main routine's name is princi.f.

Language setup

The codes in the TELEMAC SYSTEM can be run either in French or English language. A default setup is available for each and all of the users, but the user can select a customized setup.



Default setup common to all of the users For selecting the language in which a code should be run, one has to:

• edit the "systel.ini" file. This "text" file occurs at the following place in the TELEMAC tree: "systel90|config|systel.ini"

• in the "[GENERAL]" section, replace the value of the "LNGxxx" parameter (where "xxx" denotes the code initials) with the following value:

"1" for the French language

"2" for the English language An extract of this file is given below as an example illustrating an operation in French language for all the codes:

[GENERAL] #--- Langues LNGTEL=1 LNGTEL3D=1 LNGSTB=1 LNGTSE=1 LNGSUB=1 LNGPOSTE=1 LNGARTE=1 LNGSISY=1 LNGCOWA=1

That setup is available for all of the users when it is performed in the shared master configuration file "systel90|config|systel.ini".

User-customized setup Setting up the user's specific language consists in getting a personal copy of the configuration file; the copy is used in lieu of the shared "master" file (it's the same with every other parameter). In order to set up such a specific language:

• copy the directory "systel90|config|" in a user's private directory (for example under UNIX "$HOME/config" through the command "cp –r systel90/config $HOME/.")

• create the environment variable "SYSTELCFG" pointing towards that directory (e.g. under UNIX through the command "setenv SYSTELCFG=$HOME/config" or "SYSTELCFG=$HOME/config ; export SYSTELCFG ")

The next time one of the codes in the TELEMAC System is started, that private copy of the configuration file will be operated on in lieu of the TELEMAC tree master file.



Processing the results

The result files in the TELEMAC System codes are structured in accordance with specific formats (for instance, the "selafin" format).

They are most often processed by the graphics post-processor RUBENS.

Under UNIX and under WINDOWS-NT, these binary files are formatted in accordance with the "IEEE big endian" standard (this is the natural standard with UNIX, but the native format WINDOWS-NT is rather " IEEE little endian", which then is not adopted here).

Thus (unlike the earlier version 4.0), these result files in binary mode can be transferred between UNIX and WINDOWS NT machines.

Interrupting and deleting a computation

The launchers of the TELEMAC System codes construct for the user a command file that makes it possible to:

• interrupt a computation under way1 • delete the temporary files and job directory

The name of that file is of the kind "delete_name_of_steering_file".

Running Matisse and Rubens

With the new installation on Windows, the options are identical for both Matisse and Rubens: -a English version -h Gives the available options -v VxPy runs the version VxPy -o Runs the previous version (if available)

-n Runs the new version (if available)

For example: running Matisse V2P0 in english: % matisse -a -v V2P0

1 Under WINDOWS NT, that commands file only performs the deletion of the temporary directory and the files therein.

Unlike UNIX, it has no self-deletion capability (the "delete_nomfichiercas*.bat" file remains) and it cannot interrupt a computation being under way. The latter operation should be carried out by the user through the WINDOWS NT "task manager".



ANNEXE 3: TELEMAC TRAINING A two weeks training was organised by SOGREAH in the frame of the WP03 in order to:

• install the TELEMAC system software (MATISSE, TELEMAC-2D, SUBIEF-2D and RUBENS) with basic data sets from the case studies on each partner laptop,

• teach to the modellers’ partners how to use the TELEMAC software, • built the 5 study sites’ grids, • begin to built with them their hydrodynamic and water quality models,

• define with them some policy scenarios.

This training was in Sogreah Grenoble (France) from 19th to 28 th of August.

The specialists from Sogreah involved in this training were: Pierre Lang, Yvon Mensencal, Claude Guilbaud, René Ballester, Géraldine Cara and Catherine Freissinet The training organisation has been done by Martine Monteil and Laure Vinci.

The participants to this training were:

Institutes Project participants Turkey - SUMER Okan Fistikoglu,

Ali Gul

Lebanon - NCRS Mohamad Awad Mohamad Basbous

Jordan - Faculty of Agriculture

Thair Al-Momani

Zain Al-Houri

Egypt - CEDARE Omer Elbadawy

Tunisia - CNT Ali Chouaya

The complete manuals (MATISSE, TELEMAC-2D, SUBIEF-2D, RUBENS) have been distributed to the partners during the training session and are available on request.

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Project Deliverable: D03.2 Hydrological simulation ...

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