cfd - ansys software key features and best...

Computation Fluid Dynamics – ANSYS Software Key Features

and Best Practices

Dr. Wim Slagter Lead Product Manager, ANSYS, Inc.

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ANSYS, the company • ANSYS design, develops, markets

and globally supports a comprehensive range of engineering simulation software

• Proven software technologies for o Fluid Dynamics o Structural Mechanics o Acoustics o Electromagnetics o Multiphysics

• Specialized tools, incl. o ANSYS Icepak (thermal/flow

for electronics) o ANSYS nCode DesignLife (for

fatigue) • World’s largest pool of experts

providing CFD Best Practices

Emag

Acoustics

Structural

CAD Import

Parametric Simulation

Design Exploration

Meshing

Post-processing

Fluid

ANSYS – addressing your current & future CFD challenges

Transient or steady-state Laminar and turbulent flows

Heat transfer

Buoyant flows

Incompressible / compressible

Multi-component flows, multi-phase Real gas modeling

Filters/porous regions Reactions and combustion

Moving geometry and mesh

Rotating machinery

Solution-based adaptive remeshing

1-way and 2-way Fluid-Structure Interaction Courtesy of GE Energy

Courtesy of BMW AG

Key Enablers: • Links to almost any CAD system • Parametric, persistent process • Simulation focused: allows

engineers to do simulation driven product development

• Direct modeling allows for re-animating dumb CAD (geometry without parameters) models

• Extensive modeling solutions

Engineering Productivity: Geometry Modeling Bi-directional CAD connections

Feature-Based Modeling

Direct Modeling

CAD Neutral: Direct and Feature-Based Modeling!

Setup Wizards

Engineering Productivity: Workflow

Geometry

Meshing

Problem Setup

Post Processing Customized Menus

Increased Productivity through Automation and Customization!

• Advanced physical models • High-performance solvers

Engineering Productivity: Accuracy & Speed

User-defined LES for highest accuracy; RANS for all other areas

RANS

LES Re=395

New steady-state scheme as accurate as transient Wigley hull simulation

Free surface profiles • Steady-state scheme • Transient scheme • Experiment

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Hofmann et al [20]CFD

Recondisation simulation Cavitating flow in a centrifugal pump can also be modeled in steady state

Get reliable answers faster, without compromise on flow physics!

Integrated Design Exploration & Optimization

Tradeoff Chart

Parametric CAD model

Response Surface and Sensitivity Chart

Section Length

Guide Curve Angle

Guide Curve

Radius

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Section Length

DOE generated with Design Points Guide Curve

Angle (Deg)

Guide Curve Radius

(mm)

Section Length (mm)

EFA (mm2)

Baseline 63 41 51 1100.2

Optimized 50 30 60.5 1180.4

Baseline Design Optimized Design

Gain deep insights necessary to optimize product performance, and

produce better products faster!

Drag sensitivity

Downforce sensitivity

Total pressure drop sensitivity

Total pressure drop sensitivity

Estimated downforce improvement = 41.6N Actual downforce improvement = 39.1N

Adjoint flow solver: • An understanding of the shape sensitivities with respect to design variables

in a single computation! • A quantitative performance estimate due to a design change without the

need to simulate the actual change!

Adjoint is a very efficient means of quickly exploring a design space with thousands degrees of design freedom!

Shape Sensitivities wrt Design Variables

Fluid Flow

Thermal Stress

Fluid-Structure Interaction Rigid Body FSI 1-way FSI 2-way FSI

Deformation

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Comprehensive suite of FSI capabilities for accurate prediction of

a broad range of design scenarios

• Design objective: o Maximize amplification ratio for a given size and power consumption o 3 main design parameters, i.e. gap in annular ring, internal profile of ring,

profile of external ramp • Customer benefits include:

o Explored 10-fold of design variations than would otherwise have been possible (each day 10 instead of 1)

o Improved performance 250% over original design

Customer Example: Dyson Air Multiplier™ Fan

Courtesy of Dyson

• Design objective: o To optimize the dual-outlet exhaust manifold for robust performance o 4 main design parameters, i.e. outlet diameter of the manifold, thickness

at inlet, external temperature, engine RPM • Design constraint:

o Maximum displacement should not exceed 1.5 mm!

Customer Example: Exhaust Manifold

Fluid Flow

Deformation

Von Mises Stress

Temperature

• Design objective: o To optimize the dual-outlet exhaust manifold for robust performance o 4 main design parameters, i.e. outlet diameter of the manifold, thickness

at inlet, external temperature, engine RPM • Design constraint:

o Maximum displacement should not exceed 1.5 mm!

Customer Example: Exhaust Manifold

Fluid Flow

Deformation

Von Mises Stress

Temperature

All samples report maximum deformation below 1.5 mm

Effect of engine speed and thickness at outlet on maximum deformation

www.ansys.com

THANK YOU!