© 2011 ANSYS, Inc. June 25, 2014 1

Multi-Physics Analysis with Thermo-fluidic and EM/HF simulation

Jeongwon Lee FBU Application Engineer, Ph.D

ANSYS, Inc. Korea

© 2011 ANSYS, Inc. June 25, 2014 2

Contents

• Overview of Multi-Physics Simulation Workflow

• Case Study : HFSS-Icepak co-simulation – Connector

• Case Study : Maxwell-Icepak co-simulation – Busbar

• Summary

© 2011 ANSYS, Inc. June 25, 2014 3

Multi-Physics Simulation Workflow

Maxwell

HFSS

Siwave

Q3D

Apache

Icepak

Fluent

(CFD)

Mechanical

Parameterization and Optimization

ANSYS Workbench

© 2011 ANSYS, Inc. June 25, 2014 4

Icepak vs Fluent vs ANSYS Mechanical

ANSYS Mechanical

Conduction, Radiation (No Flow)

Only Temperature

ANSYS Fluent

Conduction, Radiation and Convection

Flow and Temperature

ANSYS Icepak

Customization

Modeling, Trace import

Meshing, Electronic Libraries

ANSYS Fluent

Conduction, Radiation and Convection

Flow and Temperature

© 2011 ANSYS, Inc. June 25, 2014 5

• SIwave and ANSYS Icepak exchange both power map and temperature data

– Accounts for copper resistive losses in printed circuit boards and packages for accurate PCB temperatures

Coupling with SIwave

Current Density (SIwave)

Temperature (Icepak)

Power Map

Temperature

© 2011 ANSYS, Inc. June 25, 2014 6

• Import volumetric and surface losses from Q3D into Icepak

– Conservative mapping of loss to Icepak mesh

Coupling with Q3D Extractor

Forced convection cooling of a coaxial cable, DC computation in Q3D to compute losses for Icepak thermal simulation

© 2011 ANSYS, Inc. June 25, 2014 7

• Import resistive and dielectric loss information from HFSS into Icepak

– Volumetric and surface loss

– Conservative mapping of loss to Icepak mesh

Coupling with HFSS

Forced convection cooling of a hybrid ring plate. The model includes resistive losses in copper traces and dielectric loss in the substrate layer

© 2011 ANSYS, Inc. June 25, 2014 8

• Import resistive loss information from Maxwell into Icepak

– Magnetostatic and eddy losses

– Conservative mapping of loss to Icepak mesh

Coupling with Maxwell

Natural convection cooling of a coil and plate assembly with eddy current heating

© 2011 ANSYS, Inc. June 25, 2014 9

• Apache Sentinel TI and ANSYS Icepak exchange converged power map and convective film coefficients

– Enables thermal evaluation of package in actual operating environment to accurately simulate junction temperatures

Coupling with Apache Sentinel TI

Power Map

HTC

Apache Sentinel TI Package Model

Icepak System Model with Package

© 2011 ANSYS, Inc. June 25, 2014 10

• Import temperature data from ANSYS Icepak to ANSYS Mechanical for thermal-stress analysis

Coupling with ANSYS Mechanical

Thermal-stress simulation for a computer graphics card -performed in the ANSYS Workbench environment

© 2011 ANSYS, Inc. June 25, 2014 11

• Simplorer extracts thermal RC network models from transient parametric sweeps calculated with ANSYS Icepak

– Based on linear superposition of Icepak results

Coupling with Simplorer

Run parametric trials in Icepak

Report files from Icepak

Read Icepak files into

Simplorer

Automatic creation of RC network

model in Simplorer

© 2011 ANSYS, Inc. June 25, 2014 12

• Perform design point studies, optimization, design of experiments and robust design solutions with Icepak and DesignXplorer

Optimization with DesignXplorer

Design of Experiments solution to obtain response surface and MOGA used to find power values from measured temperatures for PBGA package model

© 2011 ANSYS, Inc. June 25, 2014 13

HFSS-Icepak Co-simulation : Connector

© 2011 ANSYS, Inc. June 25, 2014 14

Introduction

• Real world system conditions = Multi-physics environment • Areas of concern

Electromagnetics

ANSYS HFSS

CFD & Heat transfer

ANSYS Icepak

Structural

ANSYS Mechanical

RF Losses

Temperature field

Temperature dependent

EM Properties

Thermal stress

Cyclic loads

Thermal

deformation

Fatigue

Failure

Design Revisions

Frequency drifts

from intended design

Overview HFSS Design Modeler Icepak Summary

© 2011 ANSYS, Inc. June 25, 2014 15

Multi-Physics : Starting point

• Temperature field born out of EM All possible problems start here

• HFSS-Icepak analysis should follow HFSS analysis

Electromagnetics

ANSYS HFSS

CFD & Heat transfer

ANSYS Icepak

RF Losses

© 2011 ANSYS, Inc. June 25, 2014 16

Heat loss in RF/Microwave Applications

• Metals and dielectrics – both play important roles in high frequency electromagnetics

• RF losses can be converted to heat dissipation in both

• Dielectrics – heat is generated as volumetric heat density : qvol

• Electric conductors (metals)

Current flow is limited to a very narrow skin at the surface Effectively, heat is generated as surface heat flux : qsurf

© 2011 ANSYS, Inc. June 25, 2014 17

Summary of Workflow Complete

the HFSS analysis

Establish connection

for geometry sharing

Establish connection for

volume/surface losses mapping

Select volume/surface

mapping in Icepak

Complete data mapping

by selecting zones

in Icepak

Complete

the setup in Icepak

and update solution

© 2011 ANSYS, Inc. June 25, 2014 18

Setup in Icepak : Volumetric Losses

• Open EM Mapping panel in Icepak File → EM Mapping

• Select Volumetric heat losses option

• Volumetric heat losses panel Lists all Icepak Blocks and Plates Select all components for volumetric

heat losses are needed Click Accept to close panel

© 2011 ANSYS, Inc. June 25, 2014 19

Setup in Icepak : Surface Losses

• Open EM Mapping panel in Icepak File → EM Mapping

• Select Surface heat losses option

• Surface heat losses panel Lists all Icepak Blocks and Plates Select all components for surface heat

losses are needed Click Accept to close panel

© 2011 ANSYS, Inc. June 25, 2014 20

Check EM Losses Mapping

Data assigned to selected Fluent solid zones ... Total loss on zone 134 is 3.431e-24 (Watt) Total loss on zone 136 is 0.000e+00 (Watt) Total loss on zone 138 is 0.000e+00 (Watt) ∙ ∙ ∙ Total loss on zone 178 is 4.112e-20 (Watt) Total loss is : 4.0170e-14 (Watt) "Ok"

Mapped volume loss on fluent

Calculated volume loss from HFSS

Volume Losses are

well mapped

on FLUENT domain

© 2011 ANSYS, Inc. June 25, 2014 21

Post-Processing for Icepak : Temperature

Temperature field on all components

Temperature field on connectors

© 2011 ANSYS, Inc. June 25, 2014 22

Post-Processing for Icepak : Flow Field

© 2011 ANSYS, Inc. June 25, 2014 23

Maxwell-Icepak Co-simulation : Busbar

© 2011 ANSYS, Inc. June 25, 2014 24

Introduction

• Real world system conditions = Multi-physics environment • Areas of concern

Electromagnetics

ANSYS Maxwell

CFD & Heat transfer

ANSYS Icepak

Structural

ANSYS Mechanical

EM Losses

Temperature field

Temperature dependent

EM Properties

Thermal stress

Cyclic loads

Thermal

deformation

Fatigue

Failure

Design Revisions

Frequency drifts

from intended design

© 2011 ANSYS, Inc. June 25, 2014 25

Multi-Physics : Starting point

• Temperature field born out of EM All possible problems start here

• Maxwell-Icepak analysis should follow Maxwell analysis

Electromagnetics

ANSYS Maxwell

CFD & Heat transfer

ANSYS Icepak

EM Losses

© 2011 ANSYS, Inc. June 25, 2014 26

Electric Machine Electromagnetic and Thermal Coupled Design

• Important aspects of electric machine design

– Electromagnetic

– Thermal

– Thermal stress and deformation

• Electromagnetic and thermal designs are interrelated

– Losses from electromagnetic design affect thermal

– Temperature rise will change material properties

– Thermal induced mechanical stress

• Electromagnetic and thermal coupled design is highly desired

© 2011 ANSYS, Inc. June 25, 2014 27

Summary of Workflow Complete

the Maxwell analysis

Establish connection

for geometry sharing

Establish connection for

volume losses mapping

Select volume

mapping in Icepak

Complete data mapping

by selecting zones

in Icepak

Complete

the setup in Icepak

and update solution

© 2011 ANSYS, Inc. June 25, 2014 28

Post-Processing for Icepak : Temperature

© 2011 ANSYS, Inc. June 25, 2014 29

Post-Processing for Icepak : Flow Field

© 2011 ANSYS, Inc. June 25, 2014 30

Summary

• Based on the ANSYS EM/HF-Icepak coupling analysis for PCB connector and Busbar, the following conclusions can be drawn :

EM/HF simulates the Electromagnetic fields including current density,

magnetic field and EM losses on PCB connector and busbar.

Design Modeler can help the user easily sharing the geometry from EM/HF to Icepak, as well as clearing unnecessary parts to Icepak.

Information of EM losses on EM/HF simulation can be easily transferred to Icepak through the GUI based connection on ANSYS Workbench environment.

Icepak can generate meshes through Mesh-generator with a little efforts of mesh-control parameters.

Volumetric and surface losses are well mapped on the Icepak without loss of quantity. Based on these precise EM losses information, Icepak can give us physically reliable results on both flow and thermal analysis.

© 2011 ANSYS, Inc. June 25, 2014 31

Questions and Answers

Contact for Tutorial files :

Jeongwon.lee@ansys.com