radtherm – advanced thermal modeling & coupling with hwpa

RadTherm – Advanced Thermal Modeling

& Coupling with HWPA Altair EATC 2013, Turin, Italy

Antti Jussila

Your Partner in Thermal Management Solutions

2 Total Thermal Solutions

Agenda

ThermoAnalytics RadTherm Introduction

Fast Transient Thermal Solver

Coupling with HWPA

Hypermesh, RADIOSS, AcuSolve

3 Total Thermal Solutions 3 Total Thermal Solutions

Headquarters in UP Michigan • Service & Training Office in Detroit • Distributors Worldwide • European Office

ThermoAnalytics



RadTherm Thermal Simulation Software

CAE Software for

Virtual Product

Development

Thermal Analysis/

Heat Protection of

Components,

Materials, and Full

Vehicle.

Integration of testing

and simulation


Ambient Air

Solar

Loading

Conduction ALONG & THROUGH

Elements

Complete Thermal Analysis

Environmental Effects

Solar: Direct, Diffuse & Reflected

Global Position and Weather

Sky and Wind Models

Radiation

Multi-bounce Surface-to-Surface

Thermal and Solar Radiation

Automatic View Factors

Convection

Automatic Convection Library

1D Fluid Flow (Advection)

Import CFD Results

Conduction

Automatic Vertical and Lateral

Conduction

Different Part Types handle special

cases (e.g. Multi-layer, Transparent)

Solid & Shell Element Support

Radiation

Exchange

with Sky


Natural Environment Modeling


CAE Thermal Simulation

System Tools Concept 1D Models

Long Transients Solved Quickly

RadTherm

Simple 2D or Detailed 3D Geometry

Radiation, Conduction, & Convection

Long Transient

CFD

Highly Detailed 3D Geometry

Steady State or Short Transient

Optimization

Geo

metr

y D

eta

il

Simulated Time

System

Tools

CFD RadTherm


Human Thermal Model Fiala, Berkeley, TAI

physiology 20 body segments,

each with three sectors and four layers.

Thermal Model Metabolic Heating

Shivering

Respiration

Sweating

Peripheral Vasomotion

Solves Bio-Heat Transfer Equation

Predicts Skin Temp, Interior Tissue Temps, Blood Pool Temp, Core Temp


Battery Electrical & Thermal Scenarios

0.0

10.0

20.0

30.0

40.0

50.0

60.0

70.0

80.0

90.0

0 60 120 180 240 300 360 420 480 540 600

Spe

ed

(mp

h)

Time (seconds)

US 06 Drive Cycle Goal: Thermal & Electrical Modeling

of Battery Cells & Packs SAE Paper #2012-01-0117 &

2012-01-0332

Scope: Transient drive cycle with thermal &

electrical simulation

Transient hot soak & pre-heating simulation in natural environments

Evaluate battery packaging performance (insulation, cooling, etc)

RadTherm standalone OR coupled with CFD

Benefits: Simulate Packaging & design options under

real transient vehicle operation

Quantified relative benefits of various individual changes (insulation, materials, etc.) and combined effects

Determine Cooling & Packaging, Heating Capability

Combine with Total Energy Use in a vehicle e.g. HVAC study


Coupling with HyperWorks

Hypermesh

RADIOSS

AcuSolve


HyperMesh Geometry Export

Complex surface descriptions of component systems can be imported using Nastran or Patran file types Triangular and quadrilateral elements – shell conduction

Hexahedral, prism, tetrahedral and pyramid elements – solid conduction

HyperMesh generated mesh export Generate shell and/or solid mesh from starting geometry

Use “Export Solver Deck” option

Select File Type – Nastran

Save file to be imported to RadTherm


Coupling with RADIOSS

RadTherm Thermal Model (temperatures)

RADIOSS FEA/Stress Model

13 Total Thermal Solutions 13 13

Transient Brake Thermal Analysis

Goal: Brake Assembly and Component Thermal Performance

Common Scope: Brake thermal performance

3D conduction, radiation, convection

Material sensitivity study

Transient drive cycle and stop condition

Fluid flow library or coupled with CFD

Benefits: Understand design performance

Brake fluid line thermal analysis

Identify & eliminate problems before prototypes

Develop thermal verification process that works with testing process


RadTherm Thermal model

20 min Transient brake model 10 stops / vehicle velocity 0 to 96 km/hr

The brake converts the kinetic energy of a vehicle into heat generated by friction between the pads and the disc rotor

Extreme rotor heating scenario commonly used in testing

The thermal model is coupled with a CFD model to capture the convection explicitly due to the flow complexity of a multiple stop scenario

Brake geometry Rotor, pads, caliper

Heat applied to pad surface

276,000 total elements (solid conduction)

2nd Braking event 10th Braking event

Cool-off while moving Simulation Start


Radioss Coupled Simulation

Comprehensive modeling approach Heat absorbed by the rotor during the high multiple stop scenarios can cause thermal

cracking

Significant thermal stresses by the temperature variation within the assembly It is important to be able to capture the physics of this complex problem

RadTherm used to determine the temperature distribution of the disc brake

Radioss used to analyze the Von-Mises stress distribution using the imported temperatures

Coupling Approach RadTherm exports geometry with mapped temperature results in Nastran format

The geometry with temperature boundary conditions is imported to solve a bulk Radioss case

Temperature data is used as a load collector which is added to the subcase

Von-Misses stresses are calculated based on the temperature distribution

Inboard Surface Outboard Surface


RadTherm - AcuSolve Coupling

RadTherm calculates surface to surface radiation, conduction, and convection to the surfaces

CFD calculates flow characteristics and the heat transfer to the air

Calculated values are passed between each code

RadTherm CFD

HTC & Tfluid

Twall


RadTherm - AcuSolve Coupling

AcuSolve CFD model – 30 minute cool-down scenario Initial interior temperature is set to 55°C

A/C discharge temperature profile is used at inlet

Air entering the cabin through 10 ducts

Patran format is used for data exchange Ntl file is written containing H coefficient and fluid temperature data

One or multiple time step result outputs can be appended through CFD manager in RadTherm

Imported data is used as boundary conditions

RadTherm Human Thermal module Human Thermal Comfort model used to predict occupant comfort based on

environmental factors

Convection Coefficient, W/m^2-K


CFD Coupling:

Transient RadTherm + Multiple Steady-State CFD

CFD Steady-state repr. t=0

RadTherm Steady-state at t=0


0 1 2 3 4 5 6 7 8 9 Time


RadTherm Initial Thermal Model (estimated convection)

RadTherm Transient from t=0 to t=4

RadTherm Transient from t=0 to t=9


Thank You!

Antti Jussila

Email: [email protected]

Tel: 906-482-9560 ext. 107

Please, visit our booth!

radtherm – advanced thermal modeling & coupling with hwpa

Technology