RDE COM Meeting16.12.2011ACEAPage 1

Random Cycle Generator

RDE COM Meeting16.12.2011ACEAPage 2

Random Cycle GeneratorScheme

PC-Roller Test

WLTP Database(> 450TShorttrips)Max.

acceleration-Ability vehicle. (f/v)

V_profileN, Mdexhaust

v_profilePhases

Random Cycle Generator

Shiftpoints

Transmission-

model

RDE-Evaluation (bags, windows,….)

RDE results

WLTP Database(> 450TShorttrips)

WLTP Database(> 450TShorttrips)

RDE COM Meeting16.12.2011ACEAPage 3

Main principle

Speed

time

Vmax < 60 km/h Vmax 60 – 100 km/h Vmax 100 km/h

rural

RDE COM Meeting16.12.2011ACEAPage 4

0

5

10

15

20

25

30

0 500 1000 1500 2000 2500

random Cycle in s

1300 Complete Random Cycles

400 Complete Random Cycles

Rel.

Fre

qu

en

cy [

%]

Random Cycle Duration Statistical Distribution

RDE COM Meeting16.12.2011ACEAPage 5

Work Plan Testing

RDE COM Meeting16.12.2011ACEAPage 6

Work Plan TestingRandom Cycle / PEMS Testing

a_mean_pos [m/s²]

NOx [g/km]

Comparison NOx emissions of diesel hot start tests

0

0,2

0,4

0,6

0,8

1

1,2

1,4

0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9

Random Cycle PEMS

RDE COM Meeting16.12.2011ACEAPage 7

First Experiences

I. Practicability- System readiness about 50% (10 weeks basis)- Modifications needed on cars - IUVP critical - Stationwagon cars and SUV’s most suitable- legalization from authority

II. Sources of errors1. Device issues

1. PEMS-tests not reproducible2. No plausibility check possible3. Need to ensure correct operation of PEMS before every test

2. Ruggedization

III. Safety - Risk of CO-exposure - Mounting of equipment - Risk of burning due to accessible pipes - Drive on public roads with Helium and Hydrogen bottles

PEMS

RDE COM Meeting16.12.2011ACEAPage 8

Timeline

RDE COM Meeting16.12.2011ACEAPage 9

Timeline

RDE COM Meeting16.12.2011ACEAPage 10

Timeline

Lab procedure: • First prototype of Random Cycle available in mid Jan 2012.• Generator is based on a Matlab tool to be used by everyone.• Total new approach in the emission legislation (No experience).• Driveability information so far limited to fixed RDE cycles

(one time effect).• Prototype allows to “simulate” PEMS road testing @ lab by

choosing similar profile, check comparability to road measurement

Road procedure:• PEMS measurements in principle known for HD, but application for

PC new.• First experiences exists for some weeks show already the need for

further investigation. • Very few (<10) PEMS measurement results in the database.