ANSYS CFD v14 5 ANSYS CFD v14.5

Update Seminarp

CAE Associates Inc. and ANSYS Inc. Proprietary© 2013 CAE Associates Inc. and ANSYS Inc. All rights reserved.

Outline

Design Iteration/Optimization using CFX and DX— Demo

O FSI— One-way FSI

ANSYS Meshing v14 5 ANSYS Meshing v14.5

ANSYS CFX v14.5

ANSYS Fluent v14.5

Shape Optimization using Fluent Adjoint MethodD

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— Demo

Design iteration/optimization in DX

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Outline

Design Iteration/Optimization using CFX and DX— Demo

O FSI— One-way FSI

ANSYS Meshing v14 5 ANSYS Meshing v14.5

ANSYS CFX v14.5

ANSYS Fluent v14.5

Shape Optimization using Fluent Adjoint MethodD

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— Demo

Fluent Meshing - TGrid Fluent Meshing Mode (integrated

) f CTgrid) for advanced CFD meshing• Faceted-CAD based meshing:

Import from CAD, Mesh and STLF d ti f f t ll l• Foundation for future parallel meshing

Faster turnaround for cases with large, complex meshescomplex meshes

• No file I/O between meshing and solving

• Mesh in serial then solve in parallel

User interface of the Fluent Meshing Mode. (Displayed model depicts human stomach

imported directly into Fluent in STL format). • Mesh in serial then solve in parallel

via dynamic process spawning• Automate and customize via

Scriptingp g Fluent (with TGrid meshing) in

Workbench• CAD import New Fluent (with TGrid meshing) component

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p• Solver parameters

New Fluent (with TGrid meshing) component available in ‘Component Systems’ and added in

‘Project Schematic’

Fluent meshing – CutCell

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Advanced CFD meshing for

Fluent Meshing -- TGrid

Advanced CFD meshing for large-scale, complex meshes

– Wrapper technology for massive geometry simplification and

HexCore with Inflationg y p

surface (re)meshing– Advanced prism/tet/HexCore

meshing for large meshes Wrapper

Tet

• > 100 million cells– Size functions, inflation, and

assembly meshingCavity

Re-meshingCavity

Re-meshingCavity

Re-meshing

– Extended meshing and mesh editing controls and tools

– Scripting

ANSYS Meshing backup tool– CAD import, size functions,

surface meshing inflation

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surface meshing, inflation, assembly meshing

CutCell

How can Fluent Meshing extend WB Meshing?

● Workbench Meshing is the proposed meshing solution, Fluent Meshing is a complement. With Workbench Meshing, you have ease-of-use, parametric and persistence throughout the meshing , p p g gprocess. But if the time/quality does not meet client needs for a specific model, Fluent Meshing could be your back-up solution.

● Note that geometry/mesh changes are not parametric with Fluent Meshing, except using advanced scripting

● Fluent Meshing has extended capabilities to produce high quality meshes

● Fluent Meshing is directly available to all Fluent users without any additional cost or licenses

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• Patch Independent technology

ICEM CFD

• Patch Independent technology– Dirty CAD, third party geometry, etc– Faceted data, scan data, STL– Combinations of CAD facets mesh

>250 million cell – Combinations of CAD, facets, mesh

• Efficiently mesh large/complex models with extended mesh controls

• Integrated geometry and meshing

million cell assemblies

Integrated geometry and meshing solution

• Hexa mesh, structured or unstructured, with automatic

St t(MultiZone) or advanced interactive blocking control

• Extended mesh diagnostics and advanced interactive mesh editing

Structured Hexa

mesh

advanced, interactive mesh editing• Flexible output for many solvers

– CFD, FEA, neutral formats…Available from Workbench

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• Available from WorkbenchInteractive Mesh Editing

Interactive Mesh Editing

Interactive Mesh Editing

• Similar to other Workbench systems

ICEM CFD 14.5 in Workbench

• Similar to other Workbench systems• Can drop on to a Design Modeler system or a Workbench

Meshing system• Transfers geometry and/or mesh

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Outline

Design Iteration/Optimization using CFX and DX— Demo— One-way FSI

ANSYS Meshing v14 5 ANSYS Meshing v14.5

ANSYS CFX v14.5ANSYS CFX v14.5

ANSYS Fluent v14.5

Shape Optimization using Fluent Adjoint Method

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— Demo

Mesh Motion Constrained Parallel to Boundary

S f h i ll d t lid Surface mesh is allowed to slide over original boundary mesh

No underlying geometry t tirepresentation nor

parameterization is required More complex geometry motion is

ibl ith i l hpossible with a single mesh topology

• Further minimize the need for interpolation between meshesinterpolation between meshes

• Mesh quality (e.g. orthogonality) is maintained over larger range of motiong g

• Less user-specified mesh motion controls are required

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Check valve with solution‐ dependent geometry motion, showing improved the mesh quality as the ball oscillates 

to a steady position 

Mesh Motion Constrained to Surface of Revolution

The user defines the axis of rotation The user defines the axis of rotation The surface mesh is allowed to slide on

the surface defined by axis and radial profile from initial boundary meshprofile from initial boundary mesh

Assumes constant radius at each axial position

Allows mesh motion beyond initial Allows mesh motion beyond initial boundary mesh

Key application is blade flutter (turbomachinery)(turbomachinery)

— Oscillating blade tip motion slides on shroud surfaceI d b t t— Improved robustness to

greater amplitudes— Maintains the mesh quality

Surface of Revolution boundary condition

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Surface of Revolution boundary condition for mesh motion constraint on moving valve and fluttering blade

Mesh Displacement Relative to Initial Mesh

Important feature for periodic— Important feature for periodic motion

• Avoids accumulation of error over timeover time

• Ensures consistent mesh from cycle to cycle

— Typical applications• Piston motion• Blade oscillationsBlade oscillations

Simulation of a vibrating turbine with prescribed ill bl d i l h bl d h d

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oscillatory blade motion normal to the blade chord, where consistent mesh is essential

Transient Blade Row Methods

● Continuous focus of turbomachinery development in recent● Continuous focus of turbomachinery development in recent releases and going forward in future releases

● Aim to minimize computational effort (CPU and Memory) for t i l ti f t i t i t ti b t bl daccurate simulation of transient interaction between blade rows

● Introduced in R14.0, enhanced and extended with R14.5

TBR methods require only 1-2 blade passages per blade row while still

capturing transient i t ti t l

TBR methods are designed for efficient simulation of transient

i t ti h th it h b t

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interaction accurately interaction where the pitch between blade rows is unequal (i.e. a ≠ b)

Transient Blade Row Applications

Single StageSingle StageSingle StageSingle Stage MultistageMultistageMultistageMultistage

Blade FlutterBlade FlutterBlade FlutterBlade FlutterGust AnalysisGust AnalysisGust AnalysisGust Analysis Blade FlutterBlade Flutter

PeriodPeriod

disp

lace

men

tdi

spla

cem

ent

Blade FlutterBlade Flutter

Period

disp

lace

men

t

Gust AnalysisGust AnalysisBlade Row

Gust AnalysisGust AnalysisBlade Row

IBPAIBPADam

ping

Coe

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ampi

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NbjjNb

IBPA

IBPADam

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Blade Flutter Analysis

Pragmatic approach to assessPragmatic approach to assess propensity to flutter

• Determine natural frequency of blade and its mode shapes, in a modal analysis

• Apply specified blade motion, based on modal analysis, in fluids simulation

• Assess system stability, looking at aerodynamic damping of prescribed blade vibration

• Result: prediction of whether or not• Result: prediction of whether or not blade will flutter

Can be applied to full wheel or use Fourier Transformation (FT) TBRFourier Transformation (FT) TBR method

Numerous related enhancements in support of this type of blade flutter l h b d ( ) d

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support of this type of blade flutter analysis

Axial compressor with prescribed motion (top) and resultant pressure fluctuations at 90% span (bottom)

Blade Flutter Analysis

Export of mode shapes from a modal p panalysis in ANSYS Mechanical with new functionality to create CFX profile file

Profile visualization and rendering to gverify profile alignment/scaling, check geometry

New mesh motion boundary condition yoption for periodic displacement

• User need only specify mode shape (profile), frequency, scale factor and phase anglephase angle

Solver assessment of work/power (per unit area) on the blade to assess aero-elastic damping of the applied motionelastic damping of the applied motion

Related general enhancements• Mesh motion, solution monitoring, …• Details on other slides

The ability to visualize imported profiles allows a priori confirmation of proper

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• Details on other slides allows a priori confirmation of proper alignment of mesh and profile

Vista CPD (Centrifugal Pump Design)

Workbench Integration of Vista CPD

( g p g )– Native Workbench application– Ability to use Vista CPD directly create

• Blade geometry model• Blade geometry model• Throughflow analysis • Volute geometry and mesh

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RPI Wall Boiling Model Enhancements

Model robustness improvements Model robustness improvements Additional control and flexibility

• Under-relaxation specification of wallspecification of wall superheat

• Consistent under-relaxation of individual

R14.0

relaxation of individual wall heat partition components

• User-specified areaR14.5

• User-specified area factors β

• User-specified additional components of wall heatcomponents of wall heat partition β

Key target application is fuel bundle cooling simulations Much improved convergence in a simulation 

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bundle cooling simulations of DEBORA test facility, thanks to new under‐relaxation improvements (Courtesy HZDR)

MAPDL Outputs Component for CFD-Post

MAPDL outputs component file (*.cm file) for CFD-Post

— Allows CFD-Post to read Named Selections and boundary condition regions set in Mechanical.

— Easier to post-process Mechanical results in CFD-Post for FSI simulations.

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Outline

Design Iteration/Optimization using CFX and DX— Demo— One-way FSI

ANSYS Meshing v14 5 ANSYS Meshing v14.5

ANSYS CFX v14 5 ANSYS CFX v14.5

ANSYS Fluent v14.5

Shape Optimization using Fluent Adjoint Method

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— Demo

Monitor Fluent Solutions in Workbench

Monitor the convergence when Fluent is running in the backgroundg

Track simulation convergence while updating design pointsp g g p

Track simulation convergence when using RSM

Example of a FLUENT Residual Chart View

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Within Workbench

Design Explorer with Mesh Morpher

Use Fluent Mesh Morpher and Optimizer (MMO) parametersOptimizer (MMO) parameters with Design Explorer (DX)

Leverage the extensive Leverage the extensive optimization capabilities of DX with Fluent MMO

• More sophisticated• More sophisticated optimization

• Parameter constraintsM ltiple objecti es• Multiple objectives

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System Coupling in Workbench

• Native Workbench application for multiphysics coupling– Currently supports Fluent and Mechanical solvers– User interface fully integrated in Workbench environment

• Extensible architecture for range of coupling scenarios

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– One-, two- & n-way, static data, co-simulation…

One-way Thermal Data Transfers

In Fluent thermal boundary yconditions set “via System Coupling” allow the specification of temperature or heat flow on surfaces via System Coupling.

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y p g

One-way Thermal Data Transfers

In Mechanical a Fluid-Solid Interface can be specified pin a Steady-State Thermal System on surfaces.

The Fluid-Solid Interface automatically writes the temperature and heat flow results to an AXDT file format to the solver directory. The Fluid-Solid Interface also accepts thermal data as a boundary

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p ycondition from System Coupling.

Contact Detection for Moving Meshes

Contact detection for valves, FSI, and other applications

Detects when surfaces come within a specified tolerance and prevents collision of moving zones

• User defines how to treat contact region and whether to restrict flow

—Default porous media Contact detection in a case where the opposite sides of a box deform in a sinusoidal wave pattern

zone treatment• UDF hooks to define

contact behavior Not currently compatible with

Systems Coupling

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Contact detection used in a bouncing ball case

New Non-Reflecting Boundary Conditions

Non-Reflecting Boundary Conditions with the Pressure-Based Solver eliminate

h i l fl ti f fl Pressure pulseunphysical reflections from flow boundaries during unsteady simulations

C tibl ith i

Reflecting Non‐reflecting

Pressure pulse

• Compatible with species transport and combustion

• Compatible boundary types:types:

—Pressure outlets—Pressure inlets—Mass flow InletsMass flow Inlets—Velocity inlets/outlets

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Improved Prediction of CO

Faster and more accurateFaster and more accurate premixed flamelet model for Carbon Monoxide (CO) emissions

— Based on the Flamelet Generated Manifolds (FGM) approach

Contours of CO mole fraction

— Solves transport equations for mixture fraction (mean and variance) and reaction progress (mean and variance)

Best suited for perfectly premixed p y pcombustion

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Versatile DPM Injections

Transient spray angle profile for cone Transient spray angle profile for cone injections

— Spray angle as function of time or crank angle via profilesangle via profiles

Cone injections for sector meshes• Simulate a “pizza slice” of axisymmetric

geometrygeometry New parcel release methods for DEM and

sprays— By default a single parcel is injected perBy default, a single parcel is injected per

injection stream per time step— New parcel release methods:

—Constant parcel diameter orpconstant mass for DEM

—Constant number of particles per parcel for spray simulations

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Improvements for Eulerian Wall Film Modeling

Adaptive time stepping speeds t i t l l tiup transient calculations

Improved accuracy:— Account for surface tension

effects in film momentum equations

— Random locations of DPM 3D Wing with Slats & Flap

injections capture film separation physics more accurately

g p

New modeling capabilities:— Coupling of EWFM with

mixture and Eulerian multiphase models, including thermal coupling

— Condensation-vaporization • Design of anti icing system

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of Eulerian wall films • Design of anti-icing system• Prediction of the trajectory

Accurate modeling of Marangoni Convection

S rface tension as a Surface tension as a function of space variable (e.g. species concentration) for more accurate modeling water

Liquid ethanol

for more accurate modeling of Marangoni convection

Important applications include: ac

e

Alcohol drop falling in water

include:— Coating— Welding

f onst

ant

surf

an

sion

— Microfluidics— Film drainage in

emulsions and foamsC

ote

n

rfac

e ti

on o

f tr

atio

n)

— Drying of semi-conductor wafers

Var

iab

le s

ur

nsi

on (

fun

ctan

ol c

once

nt

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Vte

net

ha

Ethanol concentrationLiquid volume fraction

Compressible VOF Liquid Modeling

Li id ibilit Liquid compressibility improves pressure prediction at start-up and provides better solution

Box initially half submerged in

better solution stability/convergence with moving deforming meshes

Available for both single

water

Compressible  Liquid(Good results)— Available for both single

phase and multiphase models Appropriate for high

( )

— Appropriate for high pressure applications

— Sound speed post-processing is available for

Contours of pressure after the 10th time step Incompressible  Liquid

(Unphysical results)processing is available for compressible liquid

(Unphysical results)

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Better Parallel Scalability with Particles

Improved DPM parallel scalability Improved DPM parallel scalability via Improved memory management

— 2 examples:10 illi ll 500

Overall Scalability for a 10 million cell Combustor Simulation

CRAY XE AMD 2.1GHz IL16

—10 million cell combustor case scales well overall to 1024 cores (example to right)

400450500

cores (example to right)

— For another typical customer DPM ti 24

250300350

atin

g

DPM case: time on 24-way parallel reduced from 20.4s to 11.7s

100150200R

a

050

0 500 1000 1500

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NumCores

Faster Linear Solver Thanks to GPUs β

Algebraic Multi-Grid (AMG) Solver on GPUs βSolver on GPUs β

— Accelerates AMG solver for 3D coupled pressure-based solver casesbased solver cases

— Available in serial and shared memory parallel FluentFluent

— Supported on NVIDIA Fermi based GPUs with CUDA 4 1 and aboveCUDA 4.1 and above

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Outline

Design Iteration/Optimization using CFX and DX— Demo

O FSI— One-way FSI

ANSYS Meshing v14 5 ANSYS Meshing v14.5

ANSYS CFX v14.5

ANSYS Fluent v14.5

Shape Optimization using Fluent Adjoint MethodD

37

— Demo

Adjoint Method

● Adjoint Solver for Fluent j

— Fully supported in v14— Provides information about a

fluid system that is veryfluid system that is very difficult and expensive to gather otherwiseComputes the derivative of— Computes the derivative of an engineering quantity with respect to inputs for the system

Shape sensitivity to down-force on a F1 car

Lift Force (N)Geometry Predicted Resultto inputs for the system

— Engineering quantities available

• Down force drag

Geometry Predicted ResultOriginal ‐‐‐ 555.26Mod. 1 577.7 578.3Mod. 2 600.7 599.7Mod. 3 622 621.8

• Down-force, drag, pressure drop

— Robust for large meshesT t d t 15M ll

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• Tested up to ~15M cellShape sensitivity to lift on NACA 0012

More Capabilities for the Adjoint Solver

New compound observables for New compound observables for the Adjoint Solver

— Specify observables specifically for the engineeringspecifically for the engineering purpose (e.g. lift/drag ratio, mass flow rate variance)

— Easily define global— Easily define global improvement direction (minimize or maximize)

R14: Minimize drag OR i i lift

R14.5 Maximize (Lift/Drag) ratio

Use the Adjoint solver in cases with periodic boundary conditions

Translational and rotational

maximize lift (Lift/Drag) ratio

2D translation i di l — Translational and rotational

periodics— SRF, MRF, and sliding mesh

are not supported

periodic example, showing optimal displacement vector field to improve lift/drag for the blade

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are not supported for the blade