sreekanth r, rangarajan s, anand g -system simulation€¦ · driveline optimization 3- fe...

PWT CAE| System Simulation GT-SUITE User Conference | Jan 15, 2018

Passenger Car baseline Fuel Economy Validation with Test data on IDC & FE Improvement

Strategies Prediction to improve CAFE Ratings

Sreekanth R, Rangarajan S, Anand G

-System Simulation

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CONTENTSOutcome of the Seminar

1. Modelling & Validation of FE on Indian Driving Cycle in GT-SUITE.

2. Modelling FE improvement ideas using GT-SUITE as POC.

FE Challenges for Automotive

Industry

FEBaseline validation on Indian Driving

Cycle(IDC)

Component level FE ideas

1. Driveline optimization

2.Drag Coefficient & LOW RRC Tires

ECU control logic FE ideas

1. Stop-Start

2. Power-Eco mode

Summary, Conclusions

and

Future Scope

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Contents

Introduction

Baseline Fuel Economy validation on IDC

FE improvement ideas

Summary & Conclusions

Challenges & Future scope

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How to balance them..??

Background- FE Challenges

1- INTRODUCTION

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Vehicle FE improvement concept freeze

Challenges in Real World Testing Benefits with 1D GT-SUITE Simulation

Challenges and Motivation

• Vehicle performance evaluation

• Modeling using simulation tools in upstream development stages (Limited/no test data)

• Prototyping & final test

.

1- INTRODUCTION

• Prototype

• Cost involved

• Vehicle test facility

• Complexity

• No Prototype

• Less Cost

• Less efforts

• Good accuracy withRepeatability

detailed physics of

system to be modeled !!

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Physical Layout-Chassis Dyno Simulation Layout in GT-SUITE

Deliverables

1D GT-SUITE vehicle model

1- INTRODUCTION

FE Improvement

• Transmission Optimization

• Drag Coefficient & Low RRC Tires

• Start-Stop

• Power-Eco Modes

FE Validation

• Vehicle Modelling

• FE Validation on IDC

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Simulation Steps

1- INTRODUCTION

Co

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l

Co

mp

oe

nt

Le

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l

imp

rove

me

nt

Sys

tem

Le

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PO

C v

alid

ati

on

Modeling & System Integration

• Drive model

• Engine, ECU (Simple / Detailed

FRM), Fuel Cut off logic.

• Transmission, TCU

• Carbody

Driving Cycle

• Fuel Economy simulation on

IDC

FE improvement

• Component level improvement

• ECU logic improvement

Driving Cycle

• IDC

• Real World Driving Cycle/

Customer driving cycle

Component

System Level

Control Logic

Validation

IDC (Indian Driving Cycle)

• Vehicle speed & gear position target as timeprofile.

• Drive model: Speed target PID.

• Engine: Map based model with EngineBSFC map.

• Transmission: 6 speed MT gear box & FDR.

• Drag coefficient and Tire rolling resistancetarget data.

• Stop-Start logic and Power-Eco modeaccelerator pedal map scaling.

• FE validation of baseline

• Validation of Stop-Start and Power Ecomode POC with real world FE improvementdata from OEMs(Open claims/resources)

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Baseline FE validation on IDC

2- Baseline FE validation on IDC

0

1

2

3

4

5

6

0

20

40

60

80

100

0 200 400 600 800 1000 1200

Veh

icle

sp

eed

(Km

ph

)

Time(sec)

Indian Driving Cycle(IDC Cycle)

Vehicle Speed(Kmph) Gear(-)

Gear(-)

0 200 400 600 800 1000 1200

Engin

e s

peed(R

PM

)

Time(sec)

Engine speed_IDC Cycle

Baseline configuration

IDC Cycle data:

Engine speed:

3500

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0 200 400 600 800 1000 1200

Fuel

Co

nsu

mp

tio

n(g

ram

s)

Time(sec)

Baseline cumulative fuel consumption

Baseline

Baseline model Fuel Consumption-Simulation:

2- Baseline FE validation on IDC

700

Baseline FE validation on IDC

Test(Chassis Dyno) Simulation

Fuel E

conom

y(K

mpl)

15

23

-2.4%

Baseline FE Validation:

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Driveline optimization

3- FE improvement POC 1

Driveline optimization:

Engine speed comparison:

0 200 400 600 800 1000 1200

Engin

e s

peed(R

PM

)

Time(sec)

Engine speed comparison

Baseline configuration Optimized configuration

30

03500

0 6000

20

Driveline inputs in GT-SUITE:

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Base line simulationDriveline optimization

Fuel Consumption comparison:

FE improvement:

Cumulative Fuel Flow

Baseline Driveline Optimization


Fuel C

onsum

ption(g

ram

s)

Time (s)0

700

1200

Driveline optimization

Fuel E

conom

y(K

mpl)

15

23

+3 %

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Factors impacting Air drag:


Note: CAR model only for representation

Drag inputs in GT-SUITE:

Air drag reduction

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Baseline Aerodynamic drag reduction


Fuel C

onsum

ption(g

ram

s)

Time (s)

700

0 1200

Air drag reduction

15

23

Base line simulationAir drag reduction

FE improvement:

Fuel E

conom

y(K

mpl)

+3 %

15

23

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Low RRC Tires + Tire pressure up

Factors impacting Tire rolling resistance:

construction

Tire Pressure

Tire Size

Pattern


Tire model inputs in GT-SUITE:

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0 200 400 600 800 1000 1200Fuel

Co

nsu

mp

tio

n(g

ram

s)

Time(sec)


Baseline Low RRC Tires


700

Low RRC Tires

Base line simulation

Low RRC tires + Tire pressure UpFE improvement:

Fuel E

conom

y(K

mpl)

15

23

+7 %

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Stop-Start System

Start-Stop control modelled in GT-SUITE:

• Vehicle speed= 0 Kmph &

• Engine speed = Idle speed &

• Driver accelerator demand = 0 % &

• Coolant temperature > ex: 35 deg.C

Traffic

condition

Engine

Stop-Start

Selection

Stop-Start

Control in

GT-SUITE


Stop-Start in GT-SUITE:

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0 200 400 600 800 1000 1200

Fuel

Co

nsu

mp

tio

n(g

ram

s)

Time(sec)


Baseline Start-Stop System


700

Stop-Start System


Stop-Start

Fuel E

conom

y(K

mpl)

15

23

+6.7 %

FE improvement:

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Power-Eco Mode:

POWER-ECO Mode modelled in GT-SUITE:

facilitates driver to select between the 2 modes “Power” and “ECO”.

ECO mode provides better fuel economy by limiting the maximum

Torque cure.

Simulation Carried on Real

World Driving cycle


Pedal Map in GT-SUITE:

Note: While using RWDC with ECO-Mode, the zones with high vehicle

acceleration are not followed by simulation vehicle due to low max. torque in

ECO mode.

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Fuel Consumption comparison on Real World Driving Cycle:


0

30

20

0 6000

Power-Eco Mode:


Eco mode

Fuel E

conom

y(K

mpl)

15

23

+6.3 %

FE improvement:

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ECO MODE

W.r.to Base

Driver aggressiveness monitoring

systems are being implemented

Base

+3%

+6%

FE Summary & Conclusions for IDC & Real World Drive Cycle

5- Summary

+7%

W.r.to BaseSTART-STOP

FE improvement varies based on Drive

Cycle Conditions. Technologies to gain

FE without compromise in cabin comfort

are in development

+3%AERO-KIT

W.r.to Base

Low drag vehicle designs are being

developed

Ex: eliminating ORVMs, Plasma

aerodynamics

+3%

W.r.to Base

DRIVELINE OPTIMIZATION

AT, CVT, DCT Drivelines

W.r.to Base

LOW RRC TIRES + Tire

pressure up

Low weight tires, Advanced material are

the future

+7%

+6%

IDC cycle

IDC cycle

IDC cycle

IDC cycle

Real World Cycle

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Challenges in FE improvement ideas

Aero dynamic drag

•Reducing air drag will affect the air flow in frontal area and leads to lesser cooling efficiency in Radiator and intercooler etc.

•Reducing the height and width of the car will reduce the frontal area which will reduce the drag force. But which will make uncomforatability of passengers seating.

Lower Rolling

resistance•Reduced traction effect (Braking distance/Skidding)during rain or wet climatic condition .

•Poor Stability/rattling noise in High speeds.

Eco modes & Engine

start/stop •Eco mode:

•Lower performance feel.

•Engine start/stop:

•Impact on starter motor life.

•Passenger’s discomfortness due HVAC cut off.

Poor Stability & more braking

distance

Air flow

Engine start/stop

5- Summary

http://www.chevrolet.com/camaro-zl1

http://www.chevrolet.com/camaro-zl1

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Future scope

Integration of lubrication, ETM, HVAC and Vehicle cooling

Advanced engine technologies & Co-Simulation

Hybrid powertrain configurations

Efficient thermal and waste heat management

Energy synthesis and optimization

5- Summary

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Acknowledgments

Dan Marsh, P.Dimitrakopoulos & Jonathan Zeman - Gamma Technologies, USA. Amit Patankar & Sandeep Jain – ESI Group, India. Vinayaga Moorthy –DGM, Powertrain CAE, RNTBCI, Chennai, India.

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Thank You

sreekanth r, rangarajan s, anand g -system simulation€¦ · driveline optimization 3- fe...

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