Water.dist.Full.manual.V8i

5/29/2018 Water.dist.Full.manual.V8i

1/731

Bentley WaterCAD/GEMS, Water

Distribution Design and Modeling,

Full

Version V8i

TRN012650-1/0001


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Copyright Information

Bentley WaterCAD/GEMS, Water Distribution Design and Modeling, Full 2

Copyright December-2008 Bentley Systems Incorporated

Trademarks

AccuDraw, Bentley, the B Bentley logo, MDL, MicroStation and SmartLine are registered

trademarks; PopSet and Raster Manager are trademarks; Bentley SELECT is a service mark

of Bentley Systems, Incorporated or Bentley Software, Inc.

Java and all Java-based trademarks and logos are trademarks or registered trademarks of Sun

Microsystems, Inc. in the U.S. and other countries.

Adobe, the Adobe logo, Acrobat, the Acrobat logo, Distiller, Exchange, and PostScript are

trademarks of Adobe Systems Incorporated.

Windows, Microsoft and Visual Basic are registered trademarks of Microsoft Corporation.

AutoCAD is a registered trademark of Autodesk, Inc.

Other brands and product names are the trademarks of their respective owners.

Patents

United States Patent Nos. 5,8.15,415 and 5,784,068 and 6,199,125.

Copyrights

2007-2008 Bentley Systems, Incorporated.

MicroStation 1998 Bentley Systems, Incorporated.

IGDS file formats 1981-1988 Intergraph Corporation.

Intergraph Raster File Formats 1993 Intergraph Corporation.

Portions 1992 1994 Summit Software Company.

Portions 1992 1997 Spotlight Graphics, Inc.

Portions 1993 1995 Criterion Software Ltd. and its licensors.

Portions 1992 1998 Sun MicroSystems, Inc.

Portions Unigraphics Solutions, Inc.

Icc 1991 1995 by AT&T, Christopher W. Fraser, and David R. Hanson. All rights

reserved.Portions 1997 1999 HMR, Inc. All rights reserved.

Portions 1992 1997 STEP Tools, Inc.

Sentry Spelling-Checker Engine 1993 Wintertree Software Inc.

Unpublished rights reserved under the copyright laws of the United States and other

countries. All rights reserved.


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Bentley WaterCAD/GEMS

Water Distribution Design and Modeling, Full

Dec-08 Copyright 2008 Bentley Systems Incorporated Age

Day 1

8:30 Registration and Check-in

Welcome and Announcements

Hydraulic Review

Basic Working Equations

Units of Pressure and Flow

Solution Methods

How to Apply Models

What Data Do You Need?

How to Get the Data

Assessing Level of Detail

Defining Modeling Objectives

Defining Network Models

Basic Network Components

Pipes/Junctions/Boundary

Conditions

Alternative topologies

Demonstration of WaterCAD Basics

12:00 Lunch

Workshop 1 Building a Network

with Fire Flow - Construct/Solve a

basic network

Other Pressure Network Components

Pumps

Representation in Model

Generating System Head Curves

Variable speed pumps Regulating Valves

Pressure Reducing Valves

Flow Control Valves

Pressure Sustaining Valves

General Purpose Valves

Flow Emitters

Workshop 2 Building a Network

with Pumps, Tanks and PRVs -

Analyze various system scenarios with

pumping, minor losses, check valves

and reducing valves.

4:30 Q & A Session / Adjourn

Day 2

8:30 Model Calibration

Where Do You Go for Data?

What Do You Adjust and When?

Identifying Bad Data

Workshop 3 Steady State

Calibration of Field Measurements -

Applying Calibration Techniques Using

WaterCAD

Planning System Improvements

Establishing Pressure Zones

Pipe Sizing

Pump Selection and Sizing

Storage

12:00 Lunch

Workshop 4 System Design

Improvements - Plan, Develop and

Implement a system improvement

strategy and compare design costs using

WaterCADs new cost manager.

Fire Protection

Needed Fire Flow

Insurance Ratings

Sprinkler System Design

Workshop 5 Automated Fire Flow

Analysis - Calculating fire flows for a

subset of a distribution system


Day 3

8:30 Extended Period Simulations

Demand Schedules and Pattern

Data Collection

Logic Based Controls

Hydropneumatic Tank modeling

Tank modeling during EPS

Energy costing

Workshop 6 Variable-Speed

Pumping and Energy Costing

Analysis - Analyze the system's

response under time variable

conditions focusing on VSPs, logic

based controls, advanced graphing

topological alternatives, and energy

costs.

Water Quality Modeling

Why Model Water Quality?

Use of Models

Transport/Kinetics

Initial Conditions

Tracers

Water Quality Calibration

Design/Operation for Water Qu

Tanks and Reservoirs

Chlorine Modeling

12:00 Lunch

Workshop 7 Multisource Mixin

Chlorine Residual, Age and TraceAnalysis Run several water qual

analyses on an existing water mode

Criticality Analysis

Isolating valves

Distribution segments

Critical segments

Workshop 8 Analysis of Valvin

Critical Segments - Find the critica

places in your system which you ca

fix.



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Bentley WaterCAD/GEMS

Water Distribution Design and Modeling, Full

Dec-08 Copyright 2008 Bentley Systems Incorporated Age

Day 4

8:30 Transient Analysis

Basics of Transient Analysis Demonstration of Hammer for Transient

Analysis

Automating Calibration

Grouping Pipes

Entering Field Data

Calibration Optimization

Workshop 9 Automating Calibration

using Darwin Calibrator - Automatically

design pipes using genetic algorithms

Automating Design

Design Optimization Methods

Leakage Detection

Sizing New Pipes vs. RehabilitatingPipes

Setting-up Design Events

Setting-up Design Groups

Using Results of Darwin Designer

Workshop 10 Automating Design

using Darwin Designer

Automatically design pipes using genetic

algorithms

12:00 Lunch

Automating Skeletonization

Types of Skeletonization

Pipe Removal

Branch Trimming Series Removal

Parallel Removal

Protecting Elements

Conditions and Settings

Using Results of Skelebrator

Workshop 11 Skeletonizing a Large

Model using Skelebrator

Interoperability is Driving the Future of

Modeling

Available Platforms, Pros & Cons of

each, demonstrations

- Stand Alone

- MicroStation

- AutoCAD

- ArcGIS

Bentley Water GIS for Water

Distribution Systems

- Asset Management

- Map assessment and inventory

Flushing UDF and Conventional

Methods

Using fire hydrants as flushing

components

Workshop 12 Developing System

Flushing Routines


Day 5

8:30 Basic Geospatial Data Concepts

Understanding Modeling Data Geospatial data

WaterGEMS Toolbar

ModelBuilder

Nature of GIS Data

Setting up Connections

Options and Settings

Workshop 13 Automating Model

Building using ModelBuilder

Creating a model from data

12:00 Lunch

LoadBuilder Sources for Loading Data

Loading Data Formats Points,

Polygons

Meter Aggregation

Flow Distribution

Thiessen Polygons

Need for Thiessen Polygons

Workshop 14 Automating Deman

Allocation using LoadBuilder

Importing demand data from meter da

and population data

TRex

Explaining DEMS, Projections, Un

and GIS Grinds

Spatial Referencing

Units

Selection Sets

Saving Results

Workshop 15 Importing Elevation

using TRex

Importing elevations from raster grid

WaterObjects.net

Extending Modeling Capabilities

Pre-processing data

Post-Processing Data

4:30 Q&A Session/Adjourn


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Page 0Introduction

Copyright 2008 Bentley Systems Incorporated Dec-

Whats new in V8i

?

Bentley WaterCAD V8 XM/V8i

Bentley WaterGEMS V8 XM/V8i

Introduction

Major release from BentleysHaestad Solution Center

All-new technology

Free for SELECT subscribers

Upgrade pricing available

Bentleys Haestad Solution Center- Watertown, CT -

Whats V8 all about?

Speed Designed to support all-pipe models

Interoperability The only truly interoperable model in the market

Usability Easier than ever (believe it or not!)

New features Dozens of new features to maximize your ROI


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Page 0Introduction


XML

aecXML

XMpLant

TransXML

GML

DWG

A Commitment to Interoperability

WaterGEMS V8XM Edition

Windows

Stand-alone

LoadBuilder

Terrain Extraction(TRex)

ModelBuilder

AutoCADplatform

DarwinCalibrator

Darwin DesignerSkelebrator

MicroStation

platform

ArcGIS

platform

WaterCAD & WaterGEMS

WaterCAD V8XM Edition

Available

Add-ons

Included

HAMMER and SCADAConnect Available Add-on


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Page 0Introduction


V8 in a nutshell

New Hydrants element type

New VSP battery element type

Calibration & Leakage Detection

New Isolation valve element type

Criticality analysis

Fire Flow navigator

Pressure dependent demands

Network trace

Demand control center

Select by polygon

Easy-to-use Interface Stand-alone interface

MicroStation interface

AutoCAD interface (add on)

Multi background-layer support

CAD, GIS & Database

Unlimited undo and redo

Scaled, schematic & hybridenvironments

Element morphing, splitting &reconnection

Element prototypes

Aerial view and dynamic zooming

Named views

WaterCAD V8 XM Edition

WaterGEMS V8 XM Edition

ArcGIS interface shown


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Page 0Introduction


Criticality Analysis

Find distribution segments based on valving

Identify segments which are large or have manyisolating valves

Identify outages that will interfere with service

Identify impact of outages

Determine where valves are needed

V8 GIS-type Features

LoadBuilder (stand-alone)

TRex (stand-alone)

ModelBuilder (stand-alone)


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Page 0Introduction


More highlights

Better HAMMER integration

Improved hydropneumatic tank modeling

New flushing routine

Only in SELECT upgrade 3

HMI Modeling DataHMI Modeling Data(xxx.wtg.mdb)(xxx.wtg.mdb)

Stand AloneStand Alone(xxx.dwh)(xxx.dwh)

MicroStationMicroStation(xxx.dgn)(xxx.dgn)

AutoCADAutoCAD(xxx.dwg)(xxx.dwg)

ArcGISArcGIS(xxx.mdb)(xxx.mdb)

Graphics DataGraphics Data(xxx.wtg)(xxx.wtg)File Types


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Page 0Introduction


wtg.mdb

wcd

mdb

Version 7 (3)

Version 8

Pre-version 7

Export GEMSDataset

Import

Export PresentationSettings

Import PresentationSettings

wtg

wcd

xml

Earlier Versions

Update

SELECT Benefits

Network License

24 x 7 Technical Support Live Meeting Assistance

New versions! Plus updates

Access to KnowledgeBase

Home-use license


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Page 0Introduction


Bentley Institute

Anytime, any place training to maximizeproductivity for busy people

eLearning, classroom learning, distance learning

Many purchasing options, including unlimitedtraining

All training tracked and managed on BentleyLEARN Server

We found our custom workflow training approach that Bentley helpedinstitute gets our users into a productive mode much faster than with our

previous program.

George Brashear, Indiana DOT

Which version of WaterCAD/GEMS do Idownload?

Does not matter if you use stand-alone

Files are not backward compatible

MicroStation 8.9.3

AutoCAD 2004, 2005, 2006

ArcGIS 8.3, 9.0, 9.1, 9.2

Does not have HAMMER, flushing

Select Upgrade2 08.09.165.12

MicroStation 8.9.4

AutoCAD 2008 (2007)

ArcGIS 9.2 (9.1)

Select Upgrade3 08.09.400.34

MicroStation V8i

AutoCAD 2009 (2008) ArcGIS 9.3

Select Upgrade

4 (V8i)08.11.00.29


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Page 0Introduction


The EndEnjoy the new features of V8 XM/V8i


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Page 1Hydraulics Review

Dec-Copyright 2008 Bentley Systems Incorporated

Modeling Fundamentals

What is a good Model?

Hydraulics Review

Principles

Flow

Velocity

Pressure

ContinuityEnergy

Head Loss

SolutionMethods

MinorLosses


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Quiz: Types of Flow

Compressible vs. Incompressible?

Laminar vs. Turbulent?

Single Phase vs. Multi-Phase?

Closed Pipe vs. Open Channel?

Full pipe vs. Partly Full?

Newtonian vs. non-Newtonian?

Types of Applications

Water distribution

Raw water supply

Pressure irrigation

Fire protection

Sewage force mains

Cooling water

Industrial applications


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Flow

Volume/time

m3/s cubic meters/second (SI)

L/s liters/second

m3/hr cubic meters/hour

ft3/s cubic feet/second (FPS)

gpm gallons/minute

MGD million gallons/day ac-ft/day acre-feet/day

cufr/frtnt cubic furlongs/fortnight

Velocity

Velocity = Flow / Area V = Q/A

Common Units: m/s = meters per second

fps = feet per second

1 m/s = 3.28 ft/s

What is the correct range? High? Low? 1 ft/s typical (0.6 1.2 m/s)

5 ft/s high (1.5 2.5 m/s)

10 ft/s very high (>3.0 m/s)

0.1 ft/s residential (.05 m/s)


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Velocity

May also be expressed in terms of pipe diameter:

where Q = flow

V = velocity

D = diameter

k = unit conversion factor

2kVDQ=

Values for k in V = Q / k D2

English units (V in ft/s):

Metric units (V in m/s):

Q Diameter (in.) Diameter (ft.)

CFS 0.00545 0.785

MGD 0.00354 0.510

gpm 2.44 352

Q Diameter (m) Diameter (mm)

m3/s 0.785 7.85x10-5

L/s 785 0.0785


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Pressure

Force/Area

Newton/m2- Pascal (SI)

kPa Kilo Pascal

bar 100 kPa

psf pound/ft2 (FPS)

psi pound/in2 (US typical)

atm atmosphere (14.7 psi / 10.33 mca)

Gage vs. absolute

pound?

Pressure at base of column =height a liquid (water or mercury) in column ft or m water or in or mm mercury

Pressure

20 psi

1 psi = 2.31 ft

46 ft

200 kPa1 kPa = 0.102 m

20.4 m

Does the diameter matter?

? psi

46 ft

Force? Force? Force?


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Pressure Standards

Minimum 20 psi (15 m H20)

Minimum normal 20, 25, 30, 35, 40 psi (20, 25, 30 m H20)

Maximum 80, 100, 125, 150? Psi (40 60 m H20)

Continuity Principle

Conservation of mass: Mass in = Mass out

For steady incompressible flow: net flow into junction = use at junction.

Where:Qi = flow in i

th pipe into junction

U = usage at junction

=UQi


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Continuity in Tanks

For unsteady state conditions, water stored in tanks:

sum of the inflows (minus outflows) = change in storage

Where:H = water level in tank

A = tank cross-sectional areat = timeQ = flow (positive is inflow and negative is outflow)U = usage directly from tank

t

HA

dt

dHAUQNetQ i =

Energy Principle

In hydraulics, energy converted to energy perunit weight (ft-lb/lb) of water, reported inlength units (ft) called head.

3 forms of energy: (1) Pressure - p /

(2) Velocity - V2/ 2g

(3) Elevation - z

where: p = pressure = specific weight of fluid

V = velocity

g = gravitational acceleration

z = elevation

(usually negligible)


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Hydraulic Head

HGL = Hydraulic Grade Line

Static Head = Elevation + Pressure Head = HGL

Total Head = Static Head + Velocity Head

Head Loss = difference in head between points

Fluids move from highhead to low head

Flow from Higher to Lower Head

2.31p

HeadLoss

Direction of Flow

HGL

Point A Point B Point C Point D


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Head Loss Equations

Empirical relationships in turbulent flow

Darcy Weisbach Colebrook White

Swamee Jain

Hazen Williams

Manning

Darcy-Weisbach

Friction factor = f (pipe roughness ReynoldsNumber)

Re = V D / , where is the kinematic viscosity

Friction factor not constant for a given pipe

gD

LVfh

2

2

=

h = head loss = friction factor

L = Length D = diameter

V = Velocity g = acceleration due to gravity


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Page 1-Hydraulics Review


Moody DiagramDV

f

hL

L D

V 22 g

NR

DV

v

e/D

f=RN

64

Drawn Tubing

Steel or wrought ironAsphalted cast ironGalvanized iron

Cast ironWood staveConcreteRiveted steel

0.000005

0.000150.00040.0005

0.000850.0006 - 0.0030.001- 0.010.003 - 0.03

e, ft. e,mm

0.0015

0.0450.120.15

0.250.18 - 0.90.3 - 30.9 - 9

Hazen-Williams Equation

85.1

16.1

=C

V

D

kLh

Where:

D= diameter (in ft or m)

V= velocity (in fps or m/s)

C= Hazen-Williams C-factor

L = length in feet or meters

k= 6.79 for V in m/s, D in m ork= 3.02 for V in fps, D in ft

h and L in same length units


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Hazen-Williams C-Factor

C-factor Measured in field

Backed out in calibration

Loss of carrying capacity system specific

Typical values 150 very smooth ideal pipe

130 typical design for new pipe

110 reasonable value for aged pipe

20 highly tuberculated or aged pipes

Hazen-Williams Roughness, CPipe Material CAsbestos Cement 140

Brass 130-140

Brick sewer 100

Cast-iron

New, unlined 130

10 yr. Old 107-113

20 yr. Old 89-100

30 yr. Old 75-90

40 yr. Old 64-83

Concrete or concrete lined

Steel forms 140

Wooden forms 120

Centrifugally spun 135

Copper 130-140

Galvanized iron 120

Glass 140

Lead 130-140Plastic 140-150

Steel

Coal-tar enamel, lined 145-150

New unlined 140-150

Riveted 110

Tin 130

Vitrified clay (good condition) 110-140

Wood stave (average condi tion) 120


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Mannings Equation

Co = 1.49 for English units and 1.0 for metric units

V = velocity (fps or m/s)

R = Hydraulic radius = cross-sectional area/wetted perimeter(feet or meters)

h = head loss (feet or meters)

L = length (feet or meters)

n = Mannings roughness coefficient (see typical values)

Material nSmooth pipe 0.009Neat cement 0.010AC pipe 0.011Ordinary concrete 0.013Cast iron 0.015

nLhRCV o // 2/13/2=

C-factor vs. n

0.000

0.005

0.010

0.015

0.020

0.025

0.030

0.035

0.040

0 20 40 60 80 100 120 140 160 180

C-factor

Manning'sn

D/V=16s

D/V=1s

D/V=0.062s


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Comparison of Friction Equations

Darcy-Weisbach

All FluidsAll Fluids

Hard to get fHard to get f

Good for allroughness'sGood for allroughness's

Not common in the

US

Not common in the

US

Hazen-Williams

Water OnlyWater Only

Easy to get CEasy to get C

Smooth FlowSmooth Flow

Common in the USCommon in the US

Manning

Water OnlyWater Only

Easy to get nEasy to get n

Rough FlowRough Flow

Common in the US

(for sewers)

Common in the US

(for sewers)

Minor Losses

What causes minor losses?

fittings joints

bends valves

Described by coefficient Kin:

Where: K= minor loss coefficient

h = head loss due to minor loss

gKVh 2/

2=


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Minor Loss K Values

Minor Losses for Valves

For valves, a flow coefficient Cv= flow (gpm) that will passthrough a valve at a pressure drop of 1 psi

Cvcan be converted to K, the minor loss coefficient:

Where: D = diameter (in.)

Cv is a function of D, while Kis independent of D

2

4888

vC

Dk=


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Network Representation

Network represented as of links and nodes

A link has a node at each end

Nodes represent junctions, tanks and reservoirs.

Links represent pipes (2 heads)

Pumps and valves are technically links, (2 heads)

but are treated as nodes by the user in WaterCAD

LINKNODE NODE

Network Formulation

For each node there is a conservation of massequation: Node 2:

For each link there is a conservation of energyequation: Link 2 3:

1

5

32

64

QIN

QOUT

Q12 Q23

Q36Q56Q45

Q14 Q25

232512 QQQ

bQahh232332


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Numerical Problem

This results in: M conservation of mass equations

L non-linear conservation of energy equations

M+L equations and M+L unknowns

Problem - set of n non-linear equations w/nunknowns, must be solved iteratively

Distribution of Flow in Simple NetworkMethod of Balancing Heads

Hardy Cross, University of Illinois Engineering Experiment Station Bulletin 286(1936)


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Timeline of Distribution System Modeling

HardyCross

Network

FlowAnalysis

ComputerAnalysis

ofNetworks

Widelyavailable

models formainframes

and minis

PC-based

models

----Steady-state

water qualitymodels

Dynamicwater

qualitymodels

Integrated modeling- mapping -

database GIS -SCADA

-----

Contaminantkinetics

--

Optimization

1930s 1990s1980s1970s1960s 2000s Future

Multi-platformModels

Critical

AnalysisManagement

Integration ofTransparent

GIS

DetailedWater Quality

Modeling

Steady State Simulation

Data entrySet up

n equationsn unknowns

Initialsolution

Solveequations

for H and QConvergence?Calculate v, P

Results

Yes

No


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Types of Model Runs

SteadyState

ExtendedPeriod

Simulation

WaterQuality

Fire FlowAnalysis

Optimization Flushing

The EndNumerical solutions needed to solve pipe networks


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Page 2Using Models


Model Data

How do I build a Water Model?

Using Models

Overview

Getting started

Network

representation(skeletonization)

Pipe properties

Water use

(consumption,demand)

Applying themodel


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Page 2Using Models


Overview

Model = Software + Data

Model = Approximation of real world

Approximation is no more accurate than thedata provided

GIGO: Garbage In = Garbage Out

Most work involves data collection/checking

Always check results to make sure they are

reasonable

Steps in Modeling

1. Define scope of modeling

2. Select an appropriate model software

3. Learn how to utilize the software

4. Build the Model Network, Assign Demands and Elevations

5. Skeletonize the model

6. Calibrate the model

7. Define the specific situation to be modeled

8. Input the situation-specific data

9. Run the model

10. Are results reasonable? Make recommendations.Additional runs required?


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Page 2Using Models


Step 1: Define the Scope

Modelerinteractswith

SeniorManagement

Operations Engineering

Planning

Do you have these parties identified?

Step 2: Selecting a Software Package

Most software packages work

Selection criteria: technical features

support

user interface (look and feel of the software)

quality of manuals

integration with other software AKA=Interoperability

Required effort and time to build the model


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Page 2Using Models


Step 3: Learn how to use the software

Step 4: Building the Model

Model Sources

Maps form the basis for representing the system

Use CAD/GIS drawings when available

Use the latest available maps

Verify maps with as-built drawings whereneeded

Verification with field personnel


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Page 2Using Models


Step 4: Constructing the Network

Convert maps to model

Manual process or automated using CAD / GIS

Assign node/link identifiers (e.g. numbers orlabels) Naming conventions

Automatic labeling

Auto prompting

Diameter Representation

Nominal diameters vs. Actual diameters

Most important in water quality modeling

Important in small sizes (e.g. sprinklers)

What getsused?

ID

ODDiameter ID OD Area-Nm Area-ID Area-OD

6 DI 50 6.40 6.9 28.27 in2 32.17 in2 37.39 in2

6 DI 56 6.04 6.9 - 28.65 in2 32.17 in2

48 DI 50 49.78 50.8 1809.56 in2 1946.25 in2 2026.83 in2

48 DI 56 48.94 50.8 - 1881.13 in2 2026.83 in2


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Page 2Using Models


Length Representation

Actual not point-to-point

Schematic vs. Scaled Scaled - easier to use

Schematic - easier to build

3 Dimensional length Tools > Options > Project > Use 3D Length

User defined lengths

4ft

3D (side view)

3ft

5ft

Length

Elevation Representation

Used to convert HGL to pressure

What reference point do you use? Ground?

Pipe?

Customer?

Be consistent


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Page 2Using Models


Converting HGL to Pressure

548.34

57.4 psi

553.84 55.0 psi

545.79 58.5 psi

HGL = 681.00

538.32 61.8 psi

Which reference positions would you select?

Meter

545.38

58.7 psi

564.25 50.5 psi

Obtaining Elevation Data

Topo Maps

Surveying

Digital elevation models (DEM)

Global Positioning Systems (GPS)

Altimeter

Sewer / street maps

As-builts


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Page 2Using Models


Assign Demands

Water Use

Referred to as: Usage

Consumption

Demand

Loading

Demands are assigned to nodes

Unaccounted-for water use?


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Page 2Using Models


Placing Demands at Nodes

If Q(use)


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Page 2-Using Models


NodalDemand

NodalDemand

NodalDemand

NodalDemand

NodalDemand

System Production

LargeUsers

Subareas

CustomerMeter Records

Unaccounted-for Water

Top Down

Bottom UpWhich method is better?

Goal

Assign Meters to Nodes

Assign each meter to nearest node

Automated using georeferenced meters

Calculate water usage by directly accessing billing data

Good for historical/current conditions

A B

C

D

House 300 gpd

Apartment 900 gpd

Wharehouse 100 gpd

Nodes Usage(gpd)A 2100

B 1500

C 1800

D 400


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Page 2-Using Models


Distribute Areas to Nodes

Water usage can be estimated by areas such ascensus areas or meter routes

Distribute areal water use evenly among nodes inarea

Assign large water users directly to a single node

A

B C

D

Area Usage (GPD) No. of Nodes Usage/Node (gpd)

A 21000 7 3000

B 20000 4 5000

C 10000 5 2000

D 12000 3 4000

Water Usage by Land Use Define water use/acre for each land use

Define land use pattern

Assign areas to nodes

Calculate nodal water use

Future land use maps are common

A B C

D

High density residential2000 gpd/acre

Low density resid.800 gpd/acre

Commercial1000 gpd/acre

Acres in land use categories UsageNode Low Den. High Den. Comm. (gpd)

A 0 4 0 8000

B 3 3 0 8400

C 3 0 0 2400

D 0 0 6 6000


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Page 2-Using Models


Defining Peaking Factors

Peak Hour 2030

Ave Day 2000 ?

Peak Hour 2000

Ave Day 2000 ?

Peak Day 2030

Peak Hour 2030?

Peak Hour 2030

Peak Day 2000 ?

Peak Hour 2000Peak Day 2000 ?

Demand Projections Spatial and temporal population projections

Usually provided by city or regional planners

Get others to sign off on population projections

Where will high growth be? Where will large water users be?

Future water conservation and per capita usage rates

1960 1970 1980 1990 2000 2010 2020 2030

AverageDemand

Alternative demand projections

Where willwe be?...

Why?


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Page 2-Using Models


Step 5: Skeletonization

Inclusion of only the most important pipes

Trend is towards less skeletonization (morepipes)

Depends on the ultimate use for model

Archive the original model file 1st, thenskeletonize

Automated Skeletonization

FullDataBase

SkeletonizingProgram

ModelDataSet

unidirectional workflow


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Page 2-Using Models


All Pipe Model vs. Skeletonized Model

Original Model

Skeletonized Model

AA

CC

Does skeletonized model accuratelypredict behavior at nodes A and C?


Accuracy in representing the processesin skeletonized model


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Page 2-Using Models


B

If something important is happening at node B, thenskeletonized model may not be adequate


Adequacy of skeletonized model tostudy behavior in full network

Match the Model to the Application

Applications that allow greater skeletonization Master planning

Regional water quality studies

Energy studies

System head curves

Applications that require more pipes Design (in area of interest)

Designing flushing programs

Detailed water quality studies

Near fire flow nodes


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Page 2-Using Models


Step 6: Calibration

Remotely piloted control stations

Measurement Devices (Data-Loggers)

To fit the characteristics of the

hydraulic model to the bestrepresentation of the real world

Traditional Method of Managing Runs

Input File

MODEL

Output File

Input File 1 Output File 1








Input File 9 Output File 9. .

. .


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Page 2-Using Models


Scenario Manager Terminology

Scenario = single run of model contains type of run

points to alternative sets

Alternatives = data set building block of scenarios

Inheritance = building alternative and scenariosfrom previous Add = no data

Duplicate = copy but no link Child = link data sets

Scenario ManagerScenario

[type of run]

Alternatives

Demand

Physical

Initial Settings

Operational

Age

Constituent

Trace

Fire Flow

Build Model(Base Scenario)

Calculate

Scenario

Review

Results

Add

Scenario

Edit

Scenario

Scenario Cycle

Energy Cost

User Data

Logical Control

Topologies

PDD*


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Page 2-Using Models


Scenario Control Center

Scenario Management Alternatives

Current Scenario Physical: Optimized

Demand: Today

Active Topology: CurrentYear 2010 Scenario

Physical: 2010

Demand: 2010

Active Topology: New 2010

Year 2020 Scenario

Physical: Wellesley 2020

Demand: 2020


New Diameter Scenario

Physical: New Design

Demand: Max 2020


Model Data Inheritance

Typical Software Alternatives ManagementBase Physical Alt 1 Alt 2 Alt 3

Base Physical Physical Alt 1

WaterCAD/GEMSs Alternatives Management

CopyCopy

= 4 x thework!!!

Physical Alt 2 Physical Alt 3

CopyCopy CopyCopy

Physical Alt 3

Physical Alt 2

Physical Alt 1

Base Physical

Alternatives


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Page 2-Using Models


Modeling Alternatives

STEADY

Topology

Physical

Demand

Initial

Topology

Physical

Demand

Initial

EPS

Topology

Physical

Demand

Initial

Logical/

Operation

Topology

Physical

Demand

Initial

Logical/

Operation

WATER QUALITY

Topology

Physical

Demand

Initial

Logical/Operational

Age/Trace

Constituent

Topology

Physical

Demand

Initial

Logical/Operational

Age/Trace

Constituent

FIRE FLOW

Topology

Physical

Demand

Initial

Needed FireFlow

Topology

Physical

Demand

Initial

Needed FireFlow

FLUSHING

Topology

Physical

Demand

Initial

Flushing

Topology

Physical

Demand

Initial

Flushing

Modeling Practice Tips

Check the data entry frequently - GIGO

Confirm your Datum and coordinate system

Press the Green Arrow! Trial runs can show major errors

Data Entry

Plan runs before you make them

Try different scenarios and alternatives

Keep track of runs and backup files, success, failures, changes etc.

Using Model

Initial investment in training can save you time, money and faceKeep good records of significant changes, i.e. calibration methodologies

Ask knowledgeable colleagues for lessons learned

Hit by a truck or Stolen by the competition principle - train others

Ongoing Practices


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Page 2-Using Models


The EndGarbage in = Garbage out


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Building a Network with Fire Flow 1


Building a Network with Fire

Flow

Workshop Overview

In this workshop, you will lay out the water distribution system for a small

subdivision on the side of a hill. You will feed the subdivision from a tank with a

bottom elevation of 650 ft and top elevation of 680 ft. You must size all of the pipes

in the subdivision to deliver a fire flow of 1000 gpm.

Workshop Prerequisites

A fundamental understanding of Water Distribution Systems is recommended

Workshop Objectives

After completing this workshop, you will be able to:

Be familiar with the WaterCAD/GEMS interface

Layout a network

Enter element data

Use the Demand Control Center

Perform a fire flow analysis


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Getting Started

2 Building a Network with Fire Flow


Getting Started

In this section you will create a new WaterCAD/GEMS project file and enter the

projects properties.

Exercise: Creating a new WaterCAD/GEMS Project

1. Start WaterCAD V8i or WaterGEMS V8i.

2. Click Create New Projecton the Welcomedialog or select File > New.

3. Select File > Project Properties.

4. Enter Subdivision Workshopas the Title, your name as the Engineer, your

companys name for Company, and select todays date.

5. Click OK.


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The Workspace and Dockable Windows




The steps that follow will help guide you through the process of setting up your

workspace as well as working with toolbars and manager windows.

Toolbars

Toolbar buttons represent WaterCAD/GEMS menu commands. You can remove

buttons from any toolbar, and add commands to any toolbar on the Commandstab

of the Customizedialog box.

Exercise: To add or remove a button from a toolbar

1. Click the Toolbar Options (down arrow at the end of the toolbar to be

customized).

2. Select Add or Remove Buttonsto open a menu where you can add or remove

the buttons in the toolbar itself.

3. Turn the buttons on or off as needed just by clicking on the menu items.

Managers

Most of the features in WaterCAD/GEMS are available through a system of dynamic

windows called Managers. When WaterCAD/GEMS first start; the default workspace

displays the Element Symbologyand Background Layersmanagers.

The Four Possible States for each Manager:

Floating- A floating manager sits above the WaterCAD/GEMS workspace like

a dialog box. You can drag a floating manager anywhere and continue to

work.


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Docked Static - A docked static manager attaches to any of

the four sides of the WaterCAD/GEMS V8i window. If you

click and hold a floating manager, and move it, you will see

a docking dialog that looks like Figure 1, as well as individual

docking buttons along all four sides of the

WaterCAD/GEMS V8i window. When you drag the manager over one of the

four sides of the docking dialog it will dock the manager to that side of the

window and if you drag the manager to one of the individual docking buttons

along the window edges the manager will dock to that side. The manager

will stay in that location unless you close it or make it dynamic. A vertical

pushpin in the manager's title bar indicates its static state; click the pushpin

to change the manager's state to dynamic. When the push pin is pointing

downward (vertical push pin), the manager is docked static.

Docked Dynamic - A docked dynamic manager also docks to any of the foursides of the WaterCAD/GEMS V8 window, but remains hidden except for a

single tab. Show a docked dynamic manager by moving the mouse over the

tab, or by clicking the tab. When the manager is showing (not hidden), a

horizontal pushpin in its title bar indicates its docked dynamic state.

Closed - When a manager is closed, you cannot view it. Close a manager by

clicking the in the right corner of the manager's title bar. Open a manager

by selecting the manager from the Viewmenu (for example, View > Element

Symbology), or by selecting the button for that manager on the appropriate

toolbar.

Capabilities of a Docked Static Manager:

To close a docked manager, left-click the in the upper right corner of the

title bar.

To change a docked manager to a floating manager double-click the title bar,

or click and hold the mouse and drag the manager to the desired location.

To change a static docked manager to a dynamically docked manager click

the push pin in its title bar.

To switch between multiple docked managers in the same location left-click

that particular manager's tab.

Exercise: To open and dock a manager

1. Select View > Graphs.

2. When the graph manager opens, click and hold the left mouse button as you

drag it to the bottom left of the screen and place it under the Background Layers

manager.

Figure 1


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3. Select Analysis > Scenarios.

4. When the Scenariosmanager opens, click and hold the mouse button as you

drag it and place it under the drawing pane (the white space where the model

will be).

5. Select View > Properties.

6. When the Propertiesmanager opens, click and hold the mouse button as you

drag it and place it to the right of the drawing pane.

Your workspace should look like the following:

Exercise: To go back to the default workspace

1. Select View > Reset Workspace.

2. Click Yesto reset to the default layout.

Note: The next time you start WaterCAD/GEMS, your customizations you havemade to the dynamic manager display will not be there any longer.


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Setting up the Network




The following steps lead you through the setup of the network.

Exercise: Creating pipe prototypes

1. Select Analysis > Calculation Options.

2. Double click Base Calculation Optionsto open the Propertiesmanager.

Note: You may dock the Propertiesdialog if it is more convenient.3. Set the Friction Methodto Hazen-Williams.

4. Close the Calculation Optionsmanager.

5. Select View > Prototypesto set the prototype of all pressure pipes.

Note: In this workshop the pipe prototype will be set to 6-inch diameter withPVC for material and a C-factor of 150.

6. Right-click on Pipeand select New.


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7. Double click on Pipe Prototype-1to open the Propertiesmanager if it is not

opened already, and enter 6in the Diameter (in)field.

8. Click in the Materialfield, and then click the ellipsis ()to open the Engineering

Librariesmanager.

9. Click the +next to Material Libraries, then select the +next toMaterialLibrary.xmland select PVC.

10.Confirm the Hazen-Williams C Coefficientis set at 150.

11.Click Select.

Note: The Hazen-Williams Cfield automatically updates to 150once PVChasbeen assigned as the Material.


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12.Close the Prototypesmanager.

Exercise: To import a background layer

1. Select the Background Layersmanager which is already docked in the workspaceor select View > Background Layers.

2. Click the Newbutton and select New File.

3. Browse to C:\Program Files\Bentley\WaterDistribution\Starter.

4. Select Scaled_Network.dxfand click Open.

The DXF Propertiesdialog box opens.

5. Click OK.

6. Click theZoom Extents button to view the map.


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7. Select File > Save As, enter ScaledNetworkand then click Save.

Exercise: Laying out the network

1. Select Tools > Optionsand click on the Drawingtab.

2. Change the Symbol Size Multiplierto 5and the Text Height Multiplierto 10.

3. Click OK.

Note: On the Element Symbologydialog click the Drawing Style button tochoose between CADor GISstyle. If you want CAD style do the above; if

you want GIS style leave the Multipliersset to 1.0.


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4. Follow the next set of instructions to layout the network as shown in the

following picture:

Note: To view the text for the pipes and elements, it may be necessary to selectthe Labelcheck box under Element Symbologyfor each corresponding

element.

5. Start by placing T-1, since P-1 is coming out of the tank.

6. Click the Pipe Layouttool and move your cursor over to the drawing pane.

7. Right-click and select Tank.

Note: You will notice that your cursor has changed from a pressure junction toa tank symbol

8. Left-click once on the drawing to place the tank in the desired position (see

previous drawing for tank location).


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9. Move your cursor down slightly, right-click and select Junction.

Note: Again, notice how your cursor has changed from a tank to a junctionsymbol.

10.Left-click once to place J-1in its correct location and notice how P-1has

automatically been placed for you.

11.Continue laying out the rest of the junctions in the same manner until you reachJ-6.

12.After laying out J-6, right click and select Done.

13.Click on J-2and go across the diagram and click to layout J-7, then up to J-8,

right-click and select Done.

14.Connect J-7to J-4and right-click to select Done.

15.Click on J-5and move across and click to create J-9, right-click Done.

Exercise: Entering pipe data

1. Click Select and click on P-1to open the Propertiesmanager.

2. Enter the following:

Has User Defined Length? True

Length (User Defined) (ft) 450

Exercise: Entering tank data

1. Click on T-1in the drawing to change the open Propertiesmanager to the tank

properties.


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Elevation (Base) (ft) 650

Elevation (Minimum) (ft) 650

Elevation (Initial) (ft) 665Elevation (Maximum) (ft) 680

Diameter (ft) 50

3. Close the Propertiesmanager.

Exercise: Entering junction data

1. Select View > FlexTables.

2. Open the Junction Tableunder Tables Predefined.


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3. Double click Junction Tableto open the FlexTable.

4. Right click on the Labelcolumn and select Sort > Sort Ascending.

5. Enter the elevations from the table below for each node:

Junction Elevation (ft)

J-1 620

J-2 605

J-3 580

J-4 545

J-5 510

J-6 580

J-7 580

J-8 600

J-9 490


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Your FlexTableshould look like the following:

6. Close theJunction FlexTableand the FlexTables manager.

Exercise: Using the Demand Control Center

1. Select Tools > Demand Control Centerto open the Demand Control Center.

The message below will come up on your screen:

2. Read this message and when you are ready, click Yes to continue to the Demand

Control Center.


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3. Click the Newbutton and select Initialize Demands for All Elementsto add all of

the available junctions to the table so you can enter flows and patterns.

4. Right click the Demand (Base)(gpm)column header and select Global Edit.

5. Enter 20as the Valueand then click OK.

6. Click Closeon the Demand Control Centerdialog.

Exercise: Computing the model and reviewing results

1. Select Analysis > Validateor click the Validate button to verify that the model

has no problems.

2. Select Analysis > Computeor click the Compute button.


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3. When the run has completed, the Calculation Summarywindow opens.

4. To view results, select View > FlexTablesand open the Junction Tableunder

Tables-Predefined.

5. Review the Pressureand Hydraulic Gradecolumns.

6.

Open the Pipe Tableand review the results.


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7. Complete the Results Table at the end of the workshop and answer the

questions about Run 1.

Note: Make sure the units are consistent with those on the answer table. If theyare not, modify the units on the reports. Right click the column heading

and select Units and Formatting. Make the necessary changes. You also

may decrease the Display Precisionto round your values to whole

numbers.

8. Click OKwhen completed.

9. You may turn off the background layer to make it easier to find elements and

review results.

10.In the Backgrounds Layermanager, uncheck the box for Scaled_Network.


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Fire Flow Scenario



Fire Flow Scenario

In this section you will walk through the steps to simulate a fire flow at J-6 using the

Demand Alternative.

Exercise: Creating the fire flow demand alternative

1. Select Analysis > Alternatives.

2. Expand the Demand Alternativeto view the Base Demand Alternative.

3. Right click the Base Demand Alternativeand select New > Child Alternative.

4. Click the Rename button to rename the new child alternative Fire Flow at J-6.

5. Open the Fire Flow at J-6alternative.

6. Turn on J-6in this alternative by selecting the check box, and change the

Demand (Base) (gpm)to 1000.

7. Click Close.


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Fire Flow Scenario



Exercise: Creating the fire flow scenario


2. Right click the Basescenario and select New > Child Scenario.

3. Enter the scenario name as Fire Flow at J-6.

4. Double click Fire Flow at J-6to open the Propertiesmanager.

5. Select Fire Flow at J-6as the Demand Alternative.

6. Select Fire Flow at J-6and select the Make Current button.

7. Click Compute.

8. Review the results and complete the Results Table at the end of the workshop

and answer the questions about Run 2.

Note: A network of 6 inch pipes will not work well in this situation. The problemareas are most likely those pipes with the highest velocities and/or

friction slopes. Review the pipes with the highest velocities and friction

slopes in the pipe table. These pipes will need to be upsized.


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Fire Flow Scenario with New Diameters




In this scenario we are going to try to fix the problem areas from the previous fire

flow run by upsizing the pipes with the highest velocities and friction slopes.

Exercise: Creating a new physical alternative

1. Select Analysis > Alternatives.

2. Expand Physicalto view the Base Physical Alternative.

3. Right-click the Base Physical Alternativeand select New > Child Alternative.

4. Click the Renamebutton to rename the new child alternative New Diameters.

5. Double click New Diametersto open the Physical: New Diameterstable.

6. Change the diameters to the following:

Pipe Diameter (in)

P-1 10

P-2 10

P-3 8

P-4 8

P-5 8

P-6 8


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6. Click Close.

Exercise: Creating the new fire flow scenario for new diameters


2. Select Baseand then click the Newbutton and select Base Scenario.

3. Enter the scenario name as Fire Flow with New Diameters.

4. Double click Fire Flow with New Diametersto open the Propertiesmanager.

5. Select New Diametersas the Physical Alternative and Fire Flow at J-6as theDemandAlternative.


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Bonus



6. Close the Propertiesmanager.

7. Select Fire Flow with New Diametersand click the Make Currentbutton.

8. Click the Computebutton.

9. Close the Calculation Summaryand review the results.

10.Complete the table at the end of the workshop and answer the first remaining

questions about Run 3.


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Bonus



Bonus

If time permits, try annotating the pipes and junctions to view the results on a plan

view and to view how the results change over each scenario.

Exercise: To use annotations

1. Select the Element Symbologymanager which is already docked in the

workspace or select View > Element Symbology.

2. Right-click on Pipe, and select New > Annotationto open theAnnotation

Properties.

3. On theAnnotations Propertiesmanager enter the following:

Field Name Velocity

Initial Y Offset -20

Initial Height Multiplier 0.7

4. Click OK.

5. In the plan view, you can now see the placement of Velocityfor each pipe.

Note: This information was determined by the Y Offset that you entered. Theplacement of text can be changed both horizontally (X Offset) and

vertically (Y Offset).

6. Follow the same procedure to annotateJunctionsby Pressure. You may vary the

Xand Y Offsets so the plan view has the look you prefer.

7. When you have annotated the Pipes and Junctions, change the scenario using

the Scenario dropdown menu to view the updates to the annotations.


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Results Table



Results Table

Run 1 Run 2 Run 3

Pressure at J-1 (psi)



HGL at J-5 (ft)

Velocity in P-1 (ft/s)

Velocity in P-6 (ft/s)

Flow in P-3 (gpm)

Flow in P-7 (gpm)

Pipe with highest Headloss Gradient

Headloss Gradient in that pipe (ft/1000ft)


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Workshop Review



Workshop Review

Now that you have completed this workshop, lets measure what you have learned.

Questions

1. Why is the pressure so high at J-9 even though it is far from the source?

2. Why must you rely so heavily on pipes greater than 6 inch in this fairly small

subdivision?

3. What would really happen if you used the system from run 2 and had a fire at J-6

that needed 1000 gpm?

4. How does the split in flow between pipes 3 and 7 change as you change pipe

diameters? Why?


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Workshop Review



5. If another source of water were available along the highway at J-9, how might

that source affect the design?

6. What else could you do to help the pressures during normal demand periods?


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Workshop Review



Answers

Run 1 Run 2 Run 3

Pressure at J-1 (psi) 19.0 4.9 18.3

Pressure at J-6 (psi) 35.9 -22.0 24.6

Pressure at J-9 (psi) 74.8 33.6 67.7

HGL at J-5 (ft) 662.9 568.0 646.5

Velocity in P-1 (ft/s) 2.0 13.2 4.7

Velocity in P-6 (ft/s) 0.2 11.4 6.4

Flow in P-3 (gpm) 69 567 763

Flow in P-7 (gpm) 71 553 357

Pipe with highest Headloss Gradient P-1 P-1 P-5

Headloss Gradient in that pipe (ft/1000ft) 2.4 75 15

*Some answers may vary between users due to the nature of this schematic

model

1. Why is the pressure so high at J-9 even though it is far from the source?

It is located at the lowest elevation in the system.

2. Why must you rely so heavily on pipes greater than 6 inch in this fairly small

subdivision?

Streets are not laid out with water distribution in mind.

More loops would result in smaller pipes/greater reliability.

3. What would really happen if you used the system from run 2 and had a fire at J-6

that needed 1000 gpm?

You would not be able to get 1000 gpm. You would have lower flow with

higher pressures.


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Workshop Review



4. How does the split in flow between pipes 3 and 7 change as you change pipe

diameters? Why?

Initially they are the same but there is more flow through 3 as it is increased.

5. If another source of water were available along the highway at J-9, how might

that source affect the design?

You might need to make P-10 larger so it would not be a bottleneck for the

future source.

6. What else could you do to help the pressures during normal demand periods?

If possible:

Put the tank at a higher elevation (higher static head)

Operate the tank with more water in the tank (higher static head).

Increase the system looping

Add a fire pump to maintain adequate flow/pressure


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Tanks, Pumps and Valves Page 3


Tanks, Pumps, & Valves

Tanks, Pumps and Valves

TANKS/RESERVOIRS: Store water

PUMPS: Add energy to flow

VALVES: Control the flow of water


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Tanks and Reservoirs

Differences between tanks and reservoirs?

Tank and reservoir mean different things indifferent places

Tank

finite volume

water level varies over time in EPS

water level is constant steady-state

Reservoir

infinite volume and constant head(water level) in both steady-stateand EPS

Impacts of Tanks and Reservoirs

Provide emergency storage

Equalize pressures during peak flow

Balance water use throughout the day

Potential negative water quality impacts Long residence times

Poor mixing


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Pumps

Centrifugal Pumps

Pump Characteristic Curves Head

Efficiency

Brake horsepower

NPSH (req)

Head (vertical axis) = TDH

TDH = head added

Model selects operating point along curve

Q

H,e,

HP,

NPSH

3 Point Pump Curve

Pump curve is usually represented as:

Where:

hg = head imparted by pump

h0 = shutoff head (zero flow)

Q = flow

a,b = coefficients describing pump curve

Qba0hhg


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Defining Pump Curve

Usually 3 points required to define curve

Typical points are: shutoff head,

most efficient point and

maximum flow

Best fit curve can also be determined when

more than 3 points are specified

Effects of Changing Speed/Impeller

PumpHead(feet)

Discharge (gpm)

Larger impelleror higher speed

Smaller impelleror lower speed


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Obtaining Head-Discharge Curve

Manufacturer curves

Sources of curves Catalog

Test

Available even for old pumps

Older pumps may need pump performance tests

Alternate pump representation

Modeling as Discharge HGL

Flow

Head

FuturePumps


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Modeling Pump as Known Power

h=k HP/QHP=water power

added(not motor HP)

Flow

Head

Pump Curve

Variable Speed Pumps

Pump with variable speed drive

Current technology is VFDs

Reshape electrical input

Relative speed = Speed/Max Speed

WaterGEMS calculates relative speed

Can be controlled by discharge orsuction side of pump


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Variable Speed Pumps

May be worthwhile Dead end systems

Widely varying system head curves

Speed adjusted with pump affinity laws:

Must consider TOTAL Life-cycle costs: HVAC,capital, maintenance, footprint

constND

Q

3 const

DN

H

22

System Head Curve

Head needed to move a given flow thru pump

Not single curve but a band of curves Tank water levels

System demand


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System Head Curve (Simple Case)

Flow

SuctionTank

Discharge

Tank

HGL

Pump

Lift

Head

Loss

System Head Curve (Real System)

Flow

SuctionTank

DischargeTank

HGL

Pump


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SuctionTank

DischargeTank

DistributionGrid

PumpSuction

PumpDischarge

HGL

200 -200

120

400 -400

150

Creating SystemHead Curve

Automated System Head Curves

Specify pump

Range and interval of graph

Scenario (s)


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Tanks, Pumps and Valves Page 3-


Discharge (gpm)

Pump OperatingPoint

Pump Operating Point

Pump Selection

Determine design flow

Develop system head curve(s)

Check agreement of: Design flow

Operating point (s)

Best efficiency point

Check pump combinations

Verify operation in model

Examine life-cycle costs (energy cost)

Modeling


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Pump Coverage Chart for Selection

10 100 1000 10,000 100,000

1

10

100

1000

Q, gpm

h,

ft

Modeling Valves and Things Isolating valves

Control valves

composite node

link with inlet and outlet nodes

Check valve property of pipe

comes with pump

Flow emitter property of node

Altitude Valve comes with tank

Backflow preventer general purpose valve

Water meters

minor loss on pipe

general purpose valve

flow totalizer function


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WaterCAD Valves

Pressure Reducing Valve (PRV):

limit outlet pressure to preset value

Pressure Sustaining Valve (PSV):

Maintain minimum inlet pressure

Pressure Breaker Valve (PBV):

force a specified pressure loss across the valve

Flow Control Valve (FCV):

limit the flow through valve to specified amount

Throttle Control Valve (TCV):

simulate a partially closed valve (EPS)

Generalized valve (GPV):

any loss vs. flow curve

PRV States

Active

Controlledby model

Controlling limitingpressure

Open state minor

loss only

Closedstate no

flow

Inactive

no headloss

Closed

manual

no flow


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Control

5570Demand = 300 gpm

Q = 300

Closed

5570 65

Q = 0

Open

5540

Q = 300 gpm

Active Pressure Reducing ValveSetting = 55

Demand = 300 gpm

Controlling

55 250 gpm55 55

Open

55 300 gpm70 69

Closed

55 0 gpm45

Active Pressure Sustaining Valves


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Reduced Pressure Backflow Valve

Pressuredrop in psi

Flow in gpm

or

(Pipe w/minor losses)

General Purpose Valve (GPV)

Individual Element

Enter table of Q vs. Head Loss

Table usually given in pressure drop vs. flow

Specify elevation and initial status


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Water Meters

Minor loss on pipe

Usually pressure drop vs. flow given

K = 888 PD4/Q2

Typical Ks Pos. Displ./Turbine 4-14

Compound 10-35

Fire service 4-5

Flow Totalizer

Represents metering behavior of meter

Report provided for any element

Gives demands for junction elements

Gives inflow for tank/reservoir elements

Gives flow for link (pipe, valve, pump) elements

Specify begin and end of meter period


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Flow Emitter

Property of junction node

Used to represent sprinklers, orifices, pressuredependent demands

Emitter flow added to demands

Specify emitter coefficient, gpm at 1 psi

5.0)(PkQ

The EndIn theory, there is no difference between theory and practice.

But in practice, there is.


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Building a Network with Pumps, Tanks and PRVs 1


Building a Network with Pumps,

Tanks and PRVs

Workshop Overview

Given the water distribution system shown below, you will construct a model and

perform two runs. You will need to enter the data for the system using a roughness

coefficient of 100 for the pipes, which are all 10-year-old cast iron.

Workshop Prerequisites

A fundamental understanding of Water Distribution Systems is recommended

Workshop Objectives

After completing this workshop, you will be able to:

Set up element prototypes

Enter pump definitions and pump data

Model PRVs and Tanks in a network


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Creating a New Project and Prototypes

2 Building a Network with Pumps, Tanks and PRVs



In this section you will run through creating a new WaterGEMS project and setting

up prototypes for your new project.

Exercise: Creating a new WaterGEMS project

1. Open WaterCAD V8i or WaterGEMS V8i.

2. Click Create New Projecton the Welcomedialog or select File > Newto create anew project.

Prototypes

Before we get started laying out the system, we will set up a prototype for all the

pipes to be 8-inch diameter, 10-year-old cast iron pipe with a user-defined length of

1500 ft.

Exercise: Setting the pipe prototype specifications

1. Select View > Prototypesto open the Prototypemanager.

2. Left click once on Pipewithin the Prototypemanager and then click on the Newbutton.

Note: This will create a new prototype called Pipe Prototype-1.


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3. Double click on Pipe Prototype-1to open this prototype and set the Diameter(in)as 8inches.

4. Next to the Materialfield, click on the ellipsis () button to open the EngineeringLibraries.

5. Expand Material Librariesand MaterialLibrary.xmlto find the material Cast Iron.

6. Left click once on Cast Ironto display this materials properties on the right sideof the manager.

7. Click Select.

You should now have Cast Ironas the chosen Materialon the Prototype

manager.


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Note: The default roughness value for cast iron pipe is 130, since it is assumedto be new pipe in the material library.

8. Change the Hazen-Williams Cto 100by simply typing it in the field.

9. Change Has User Defined Length?from Falseto Trueusing the dropdown menu.

10.Enter in 1500in the Length (User Defined) (ft)field.

Your Pipe Prototype should now look like the one below:

11.Close out of the Pipe Prototype andPrototype managers by clicking the smallclose button.

12.Select File > Save As, name the file PumpsAndTanksand click Save.


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System Layout



System Layout

Exercise: Laying out the system

1. Now you will layout the system as shown below:

2. To begin, select the Layouttool from the tool palette.

3. Move your cursor over to your drawing pane, right-click and choose Reservoir.

4. Place the reservoir on the left hand side of the drawing window as shown above.

5. After you place the reservoir, move your cursor over, right-click and chooseJunction.

6. Place junction, J-1and then right-click to select Pump.

7. Place the pump on your drawing and then change the element type to a Junctionand continue laying out J-2 and J-3.

8. After J-3, right click and select PRVthen place the PRV as shown.

9. Next, right click, pick Junctionand layout junctions J-4 and J-5 and continuelaying out the rest of the system.

Note: Make sure to lay out the network in sequential order so that thenumbering of the network corresponds to that shown above.

10.The PRVs need to be drawn from the upstream node to the downstream node toindicate the direction of flow.


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System Layout



Hint: If you lay out a pump, valve, or pipe in the direction opposite the one youwant, you can change its direction by clicking once on the element in the

drawing window and then right clicking and choosing Reverse.

11.Before continuing, review each PRV and make sure that they are oriented

correctly (from upstream to downstream) and if they are not, use the Reverseoption to orient them correctly.

Node Downstream Pipe

PRV-1 P-6

PRV-2 P-8

PRV-3 P-16


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Entering Element Data




Enter the data for the pipes and junction nodes as provided in the following tables.

The best way to do this is using the FlexTables.

Note: Make sure your FlexTables are sorted so they match the order of theelements in the following tables before entering the data. Right click the

Labelcolumn and pick Sort > Ascending.

Exercise: Entering pipe data

1. Select View > Flex Tables.

2. Open the Pipe Tablefrom the Tables Predefinedsection, and enter thefollowing:

Pipe No. Diameter (in.) Length (ft)

P-1 12 10

P-2 12 10

P-3 12 5000

P-4 8 1000

P-5 8 100

P-6 8 1500

P-7 8 1500

P-8 8 1500

P-9 8 100

P-10 8 1000

P-11 8 1500

P-12 8 100

P-13 8 1000

P-14 8 1800

P-15 10 1500

P-16 10 1000

P-17 12 1500


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4. While you are in the Pipe FlexTable, right click on the heading for the Length

(User Defined) (ft) and pick Units and Formatting.

5. Change the Display Precisionto 0.

6. Click OK.

Note: Notice that now the lengths are displayed as 1,500 instead of 1,500.00.Notice also that many of the fields in the tables have values of (N/A). This

is because the values have not yet been calculated.

7. Close the Pipe FlexTableand save the file.


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Exercise: Entering junction data

1. SelectView > FlexTables.

2. Open the Junction Tableunder Tables Predefined.

3. Enter in the Elevationand Demanddata given below:

Node Elevation (ft) Demand (gpm) Node Elevation (ft) Demand (gpm)

J-1 820 0 J-6 890 75

J-2 820 50 J-7 890 80

J-3 870 50 J-8 910 0

J-4 770 75 J-9 905 50

J-5 770 50

TheJunction FlexTablewith the elevation data should look like the following:

Note: To enter in the Demand data, you could enter in the data within theFlexTable by clicking the ellipsisbutton () within each cell in the

Demand Collectioncolumn. This will open a table that will allow you toenter in the demand associated with that single node.

4. Alternatively, you can close out of the FlexTables and go to the Demand Control

Centerunder Tools > Demand Control Center, which is often the quicker method

of entering in demand data.

5. Click Yeswhen you are prompted with the dialog shown on the next page.


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6. Once inside the Demand Control Center, select the Newbutton and chooseInitialize Demands for All Elements.

7. Fill in the Demand (Base)column from the data in the table on the previous

page.

8. Click Closewhen done.

Exercise: Entering PRV Data

1. Open the PRV Tablefrom the FlexTables manager.


PRV Label Elevation (ft) Diameter (in) Hydraulic Grade Setting (initial) (ft)

PRV-1 820 4 935

PRV-2 830 4 940

PRV-3 830 4 940


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3. Check the PRV FlexTableto see if Hydraulic Grade Setting (Initial)is in the table.

If it is, then fill in that column and go to Step 8.

4. If it is not, you will need to add the column for Hydraulic Grade Setting (Initial)to the PRV FlexTable.

5. Within the PRV FlexTable, select the Edit button.

6. Scroll through theAvailable Columnslist, highlight Hydraulic Grade Setting(Initial), and select the firstAddbutton.

7. Using the Uparrow under Selected Columns(at the bottom), move HydraulicGrade Setting (Initial)under Diameter.

8. Select OKto update the table with the values from the PRV table on the previouspage.

Note: Make sure Labelis sorted in ascending order and enter the data from thetable.


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9. Close out of the PRV FlexTableand FlexTable manager to return to the maindrawing screen.

Exercise: Entering reservoir data

1. Open the Properties manager for the Reservoir by clicking once on R-1if your

Properties manager is docked; if it is not currently docked, simply double click onR-1and this will bring up the Properties manager.

2. Enter in an Elevation (ft)of 950 for R-1.

Exercise: Creating a pump definition and entering pump data

1. To enter in the Pump data, open the Pump Definition manager by selectingComponents > Pump Definitions.

2. Click the Newbutton.

3. Accept the default name and enter the values from the table below for a

Standard (3 Point)pump.

Flow (gpm) Head (ft)

Shutoff: 0 160

Design: 1000 130

Max. Operating: 1400 111

4. After you have entered the data, view the graph.

Note:Do not worry about the blue line. That is only used for efficiency inenergy costing which we are not doing here.


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5. Click Closeand save your file.

6. Back in the main drawing screen, click on the PMP-1to open the pumpsProperties manager.

7. Enter in the Elevation (ft)of the pump as 945.

8. Use the dropdown menu next to the Pump Definitionfield and choose the pumpyou just created.

Exercise: Entering tank data

1. Click on T-1to open the Properties manager.


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2. Enter in the data given below:

Elevation

(Base) (ft)

Elevation

(Minimum) (ft)

Elevation

(Initial) (ft)

Elevation

(Maximum) (ft)

Elevation

(ft)

Diameter

(ft)

1010 1030 1050 1070 950 50


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Run 1 AVG Daily



Run 1 AVG Daily

In this section you will run the model as is for an average daily run.

Exercise: Computing the model


2. Set up a scenario incorporating the Base-Demand Alternativeto run a steadystate analysis.

Note: The default Scenario, named Base, should be the appropriate setup.

3. Rename the Base Scenarioto AVG Dailyby right-clicking the Base Scenario,selecting Rename, and typing the new name.

4. Click the Compute button within the Scenarios manager.

5. Review the results and answer the questions for Run 1.


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Run-2 AVG Daily plus Industry



Run-2 AVG Daily plus Industry

Now, suppose that an industry wants to move into a site near junction node J-5 and

you have been asked to evaluate the adequacy of the distribution system. The new

industry demand at this node is 1500 gpm, and it is fairly steady over the day.The difference between this run and Run 1 is the increased demand. You are going

to set up a new demand alternative to create a scenario for this run.

Exercise: Creating the AVG Daily + Industry Base Demand Alternative

1. Select Analysis > Alternativesand highlight the Base Demand Alternative.

2. Right-click and choose New > Child Alternative.

3. Rename this new alternative AVG Daily + Industry.

4. Open the new alternative by double clicking on it.

5. Change the demand of J-5from 50 to 1500 gpm to simulate the industrysrequirements.

Note: Notice how there is now a check mark next toJ-5indicating that its datahas changed from that of the parent alternative.

6. Click Closeand exit theAlternativeswindows.

Exercise: Creating the

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