Two-Stage Variable Compression Ratio (VCR) System to ... Presentations/Day 1 Session 1 SI... ·...
17
Baltimore, February 25 th , 2014 Two-Stage Variable Compression Ratio (VCR) System to Increase Efficiency in Gasoline Powertrains 2014 CRC Advanced Fuel and Engine Efficiency Workshop Henning Kleeberg, Dean Tomazic, Steve Bowyer, FEV NA Inc. Juergen Dohmen, Bernd Haake, FEV GmbH Andreas Balazs, RWTH Aachen University
Transcript of Two-Stage Variable Compression Ratio (VCR) System to ... Presentations/Day 1 Session 1 SI... ·...
Baltimore, February 25th, 2014
Two-Stage Variable Compression Ratio (VCR) System to Increase Efficiency in Gasoline Powertrains
2014 CRC Advanced Fuel and Engine Efficiency Workshop
Henning Kleeberg, Dean Tomazic, Steve Bowyer, FEV NA Inc. Juergen Dohmen, Bernd Haake, FEV GmbH Andreas Balazs, RWTH Aachen University
© by FEV – all rights reserved. Confidential – no passing on to third parties
Content
Introduction and Motivation
Layout of FEV’s Two-Stage VCR System
CO2 Reduction Potential
Combination with Future Technologies
Summary and Conclusion
CRC_AFEEworkshop2014_VCR_Kleeberg_20140225.pptx 2
© by FEV – all rights reserved. Confidential – no passing on to third parties
Introduction and MotivationPrinciple Influence of Compression Ratio on Fuel Consumption
3
Compression ratio (CR) [-]
BSF
C [%
]
high
100
low
CRbase
2000 rpm / WOT
2000 rpm / BMEP = 2 bar
148
VCR
CRC_AFEEworkshop2014_VCR_Kleeberg_20140225.pptx
© by FEV – all rights reserved. Confidential – no passing on to third parties
Introduction and MotivationClassification of VCR Systems
Variable piston TDC position
min
max
Unconventional cranktrains
Variable distancehead - crankshaft
Variable kinematic lengths
4CRC_AFEEworkshop2014_VCR_Kleeberg_20140225.pptx
© by FEV – all rights reserved. Confidential – no passing on to third parties
Layout of FEV’s Two-Stage VCR SystemWorking Principle: Conrod
55CRC_AFEEworkshop2014_VCR_Kleeberg_20140225.pptx
© by FEV – all rights reserved. Confidential – no passing on to third parties
Layout of FEV’s Two-Stage VCR SystemWorking Principle: Mechanical Actuation
6
Cam disc carrier
View from top
horizontalmovement
valve body
functional surface
CRC_AFEEworkshop2014_VCR_Kleeberg_20140225.pptx
© by FEV – all rights reserved. Confidential – no passing on to third parties
Layout of FEV’s Two-Stage VCR SystemTransition Time During Load Step
7
actual CR ideal CR
high
low-0.2 0.0 0.2 0.4 0.6 0.8 1.0
2500
2000
1500
1000
500
0
CR
[-]
Acce
lera
tor
Peda
l [-]
Manifold
pressure[m
bar]
Time [s]
Full Load
Part Load
n = 2000 rpmOil temp. = 90°C
CRC_AFEEworkshop2014_VCR_Kleeberg_20140225.pptx
© by FEV – all rights reserved. Confidential – no passing on to third parties
Layout of FEV’s Two-Stage VCR SystemInfluence of Oil Temperature
8
0.0 0.2 0.4 0.6 0.8 1.0
high
low
CR
[-]
Time [s]
n = 2000 rpmBMEP = 8 barOil temp.:
0°C 90°C
CR ‘low high‘ CR ‘high low‘=
CRC_AFEEworkshop2014_VCR_Kleeberg_20140225.pptx
© by FEV – all rights reserved. Confidential – no passing on to third parties
US Emission Cycles based Simulations – Boundary Conditions
Large Passenger Car (Vehicle Weight = 1670 kg)
7-speed Wet Dual-Clutch Transmission
2.0L-I4 Turbocharged GDI Engine
Max. Power = 180 kW
Max. Torque = 350 Nm (BMEP = 22bar)
Base CR – 10.5 with Premium Fuel – 10.0 with Regular Fuel
9CRC_AFEEworkshop2014_VCR_Kleeberg_20140225.pptx
Two-Stage VCR SystemCO2 Reduction Potential
© by FEV – all rights reserved. Confidential – no passing on to third parties 10CRC_AFEEworkshop2014_VCR_Kleeberg_20140225.pptx
Two-Stage VCR SystemCO2 Reduction Potential
US Emission Cycles based Simulations – FTP 75 Results
FTP 75Full size sedan
Baseline CR = 9/12 CR = 9/13 CR = 9/14 CR = 10/12 CR = 10/13 CR = 10/14
CO
2 Em
issi
ons
[g/k
m]
170
175
180
185
190
195
200 Premium Fuel Regular Fuel
-4.8%-3.9%-2.8%
-4.5% -5.3% -6.0% -4.8% -6.5%-5.6%
-2.8% -4.0% -4.8%
CR
= 1
0.5
CR
= 1
0
© by FEV – all rights reserved. Confidential – no passing on to third parties 11CRC_AFEEworkshop2014_VCR_Kleeberg_20140225.pptx
Two-Stage VCR SystemCO2 Reduction Potential
US Emission Cycles based Simulations – FTP 75
Fuel share in FTP75 [%]
BM
EP [b
ar]
0
2
46
8
10
12
14
16
18
20
22
24
Engine Speed [rpm]1000 2000 3000 4000 5000 6000
Turbocharged DI 2.0L CR=10/14
CR = 14
CR = 10
6
5
4
3
2
1
0
© by FEV – all rights reserved. Confidential – no passing on to third parties 12CRC_AFEEworkshop2014_VCR_Kleeberg_20140225.pptx
Two-Stage VCR SystemCO2 Reduction Potential
US Emission Cycles based Simulations – US06
BM
EP [b
ar]
0
2
4
6
8
10
12
14
16
18
20
22
24
Engine Speed [rpm]1000 2000 3000 4000 5000 6000
Turbocharged DI 2.0L CR=10/14
CR = 14
CR = 10
8
7
6
5
4
3
2
1
0.8
0.5
0.3
0
Fuel share in US06 [%]
© by FEV – all rights reserved. Confidential – no passing on to third parties
Two-Stage VCR SystemCombination with Future Technologies
Alternative Fuels
Gasoline ControlledAuto Ignition (GCAI)
13
‘Extreme Downsizing’
CRC_AFEEworkshop2014_VCR_Kleeberg_20140225.pptx
© by FEV – all rights reserved. Confidential – no passing on to third parties
Combination with Future TechnologiesTwo-Stage VCR Combined with GCAI - Gasoline Controlled Auto Ignition
14
Base vehicle: 1372 kg, 1.8L -4% CO2 in NEDC
Fixed CR = 9.8
GCAI operation area
Load too low for GCAI
Two-stage VCR CR = 9.8/13-12% CO2 in NEDC
Load too high for GCAI
CRC_AFEEworkshop2014_VCR_Kleeberg_20140225.pptx
© by FEV – all rights reserved. Confidential – no passing on to third parties
Two-Stage VCR SystemCombination with Future Technologies
15CRC_AFEEworkshop2014_VCR_Kleeberg_20140225.pptx
Two-Stage VCR Potential for Alternative Fuels
© by FEV – all rights reserved. Confidential – no passing on to third parties
Two-Stage VCR SystemSummary and Conclusions
VCR can help to resolve the conflict between part load and full load CR layout especially for boosted downsized gasoline enginesThe presented two-stage VCR system is based on a variable length conrod with eccentric piston wrist pin suspension and can be adapted with moderate effort to existing enginesVarious CR settings can be chosen with small conrod design changesThe transition duration of the system with 0.6 seconds is sufficiently short especially for boosted engines and is almost independent from oil temperatureCO2 reduction potential for moderately downsized GDI engines 5 – 7% within the FTP75 cycleOperating area of GCAI technology can be significantly enlarged resulting in up to 12% CO2 reduction in combination with two-stage VCR in NEDCThe higher knock resistance of alternative fuels can be used via adaptation of the VCR shift line in the map
16CRC_AFEEworkshop2014_VCR_Kleeberg_20140225.pptx
© by FEV – all rights reserved. Confidential – no passing on to third parties
2014 CRC Advanced Fuel and Engine Efficiency WorkshopTwo-Stage Variable Compression Ratio (VCR) System
Thank you for your attention!
17CRC_AFEEworkshop2014_VCR_Kleeberg_20140225.pptx
