The Role of Simulation at Change

Daimler AG

Full Vehicle Thermal Management (VTM)

Seite 2The Role of Simulation at Change/Walter Bauer RD/FNT / 01.06.2016 /

How is simulation integrated into the development process?

What are the success factors of simulation of today?

Are simulation and testing equivalent ?

Daimler AG

• ca. 400 000 cells

• 3 weeks of computation time

• 9 months for meshing

• Role of simulation: nice to have

The Role of Simulation at Change/Walter Bauer RD/FNT / 01.06.2016 / Seite 3

First Generation of Simulation Model for Underhood (1990)

Daimler AG

•1.4 Mio cells in total

•1.0 Mio engine compartment

•0.2 Mio underbody

•0.2 Mio external region

•Role of simulation: treated more serious

Second Generation of Simulation Model for Underhood

The Role of Simulation at Change/Walter Bauer RD/FNT / 01.06.2016 / Seite 4

Daimler AG

Latest Generation of Simulation Model for VTM

Seite 5The Role of Simulation at Change/Walter Bauer RD/FNT / 01.06.2016 /

•120 Mio cells (Hexahedral mesh)

•40 Mio cells (Polyhedral mesh)

•Role of simulation: fully accepted

Daimler AG

� Vehicle components

� Exhaust system

� Heat exchange package

� engine

� Dynamic load cases

� Reproduction of the time depend temperature behavior of all thermal relevant components

Latest Generation of VTM Physical Modeling

The Role of Simulation at Change/Walter Bauer RD/FNT / 01.06.2016 / Seite 6

Daimler AG Seite 7The Role of Simulation at Change/Walter Bauer RD/FNT / 01.06.2016 /

Load case vmaxLoad case up hill drive

Load Cases - vmax, up hill drive,

etc.

Full VTM Process Testing

Simulation -

which boundary conditions ?

Daimler AG8

Safety of Prediction Flexibility Efficiency

General Requirements on Full VTM Simulation

The Role of Simulation at Change/Walter Bauer RD/FNT / 01.06.2016 / Seite 8

Omission of Vehicle

Hardware Substitution

by Simulation

Shortening and Modifications of

Development Process

“Mass Production of VTM

Simulation”

0

10

20

30

40

50

60

70

Duration of a CFD Simulation [days]

Daimler AG

Continuous Improvement Process for VTM Simulation

Source: M. Disch (upcoming Ph.D thesis, FKFS)

The Role of Simulation at Change/Walter Bauer RD/FNT / 01.06.2016 / Seite 9

Dissertation Dr. Weidmann

„Engine Soak“�

Dissertation Mario Disch

Simulation Transient Driving Up hill

Dissertation Frau Michel

„Transient Load Cases TAG E/E“

Dissertation Frau Urban

„Water Separation“

Dissertation Herr Enriquez-Geppert

„Modeling Full Exhaust System“�

�

75

85

95

105

115

300 600 900 1200 1500 1800 2100

Zeitachse [s]

Tem

pe

ratu

r [°

C]

0

5

10

15

20

25

30

35

40

Ges

ch

win

dig

ke

it [

km

/h]

Oberflächentemperatur Bauteil Geschwindigkeit

PHASE 1Aufheizung

PHASE 2stationär

PHASE 3Nachheizen

Dissertation Frau Pulz

„Modeling Full Engine/Transmission“�

�

Daimler AG Seite 10The Role of Simulation at Change/Walter Bauer RD/FNT / 01.06.2016 /

Generic Digital Prototype Process

Daimler AG Seite 11The Role of Simulation at Change/Walter Bauer RD/FNT / 01.06.2016 /

Full Vehicle Thermal Management Process

Evaluation

Component Temperatures

Digital E-Vehicle

Evaluation

Global Concept

Digital Phase 1

Evaluation

Local Concept

Digital Phase 2

Digital B-Vehicle

E-Vehicle-

Testing

B-Vehicle-

Validation

Start of Project SoP

Optimization Component

Temperatures

Digital AssessmentDigital and Physical

Assessment

Tandem of simulation engineer and testing engineer is responsible for VTM

Daimler AG

VTM Co-Simulation

Seite 12

Thermal Convection

Thermal Conduction

Thermal Radiation

The Role of Simulation at Change/Walter Bauer RD/FNT / 01.06.2016 /

• Change from pure CFD

engineer towards VTM

engineer

• Increase of the complexity

of simulation

Daimler AG

Costs of VTM

The Role of Simulation at Change/Walter Bauer RD/FNT / 01.06.2016 / Seite 13

Flow Mesh

Generation

Solid Mesh

Generation

Analysis

Analysis

Result

Preparation

Result

Preparation

Co

Sim

CAD data

preparation

Result

Assessment

License costsEngineer service costs ? Engineer service costs ?

Reducing the number of physical prototypes increases costs for digital prototypes

Daimler AG14

Efficient Full VTM Simulation Process

The Role of Simulation at Change/Walter Bauer RD/FNT / 01.06.2016 / Seite 14

Pre-ProcessingTools used: TIG** , STAR-CCM+

• Need for Automation

• Investment in Software

CAD-PreparationTool used: Model Manager**

• Need for Automation

• Investment in Software

**Customized Software Tools for Daimler

ProcessingTools used: Event Manager,**

STAR-CCM+

• Need for Automation

• Investment in Software

Post ProcessingTools used: Post Tools,** STAR-CCM+

• Need for Automation

• Investment in Software

0

2

4

6

8

10

12

14

Vehicle 1 Vehicle 2 Vehicle 3 Vehicle 4

Number of Referenz Vehicles per DPT Loop

0

1000

2000

3000

4000

5000

6000

7000

8000

2008 2009 2010 2011 2012

Number of Components per Vehicle

Daimler AG15

Imprinting of adjacent Component Parts by means of LFE Tools

The Role of Simulation at Change/Walter Bauer RD/FNT / 01.06.2016 / Seite 15

Daimler AG

Full VTM Post Processing

Seite 16The Role of Simulation at Change/Walter Bauer RD/FNT / 01.06.2016 /

Daimler AG

Key Factors for successful VTM simulation

• Geometrical Data for Pre processing

• Powerful Simulation tool

• Post processing

• Simulation process

Robust and flexible

Costs effective

• External Costs for VTM

• License Fee

• Engineering Services

• Software Development

Seite 17The Role of Simulation at Change/Walter Bauer RD/FNT / 01.06.2016 /

Daimler AG

New Role of Full VTM Simulation

Simulation is

• dominating the development process

• accepted by the management

• under costs and time pressure more than ever

• comparable to testing

Simulation engineers have more responsibility

Seite 18The Role of Simulation at Change/Walter Bauer RD/FNT / 01.06.2016 /

Thank you for your attention!