Post on 15-Aug-2020
Caterpillar Engine Research
An Engine System Approach to Exhaust Waste Heat Recovery
Principal Investigator: David J. Patterson DOE Contract: DE-PS26-04NT42099-02 Presenter: Richard W. Kruiswyk DOE Technology Manager: John Fairbanks Caterpillar Inc. NETL Program Manager: Ralph Nine 15 August 2007 DEER Conference
Note: This presentation does not contain any proprietary or confidential information.
� Program Objectives
� Technical Approach
� Accomplishments
� Packaging Concepts
� Summary and Conclusions
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Program Objectives
� Recover energy lost in the exhaust processes of an internal combustion engine and utilize that energy toimprove engine thermal efficiency
� Improve engine efficiency with: � No increase in emissions
� No reduction in power density
� Compatibility with anticipated aftertreatment
� TARGET – Demonstrate 10% improvement in overallthermal efficiency (OTE)
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Ambient
Stack
Engine C15
A/C
LP Comp
HP Comp
LP Turb
HP Turb
DPF
CGICooler
HP Turb
Technical Approach
Recover energy lost
in the exhaust
processes
Baseline Engine
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CGI
Brake Power
Ambient
Stack
Engine C15
A/C
LP Comp
HP Comp
LP Turb
HP Turb
DPF
CGI Cooler CGI
BrakePower
Ambient
Stack
Engine C15
A/C
LP Comp
HP Comp
LP Turb
HP Turb
DPF
CGICooler
HP Turb
0.00
50.00
100.00
150.00
200.00
250.00
Ava
ilabl
e E
nerg
y (k
w)
Technical Approach
CGI
Brake Power
A/C
Ambient CGI
BrakePower
~ 34% of Exhaust availability used
~8% (primarily ports)
~16% (throttling, turbines, DPF)
~ 34% exits stack
~8% CGI flow (dumped)
Need System Level Approach to Maximize Exhaust Recovery
Peak Torque ConditionEngine C15
HP Comp HP Turb
Stack
LP Comp LP Turb
StackDPF
EnergyCGI
Cooler
Destruction
Heat LossCGI Energy
LP Work
HP Work
From Cylinder Caterpillar Confidential: XXXXEngine Research
Ambient
Stack
Engine C15
A/C
LP Comp
HP Comp
LP Turb
HP Turb
DPF
CGICooler
HP Turb
turbines, DPF)
umped)
~8% (primarily ports)
~8% CGI flow (d
Technical Approach
0.00
50.00
100.00
150.00
200.00
250.00
Ava
ilabl
e E
nerg
y (k
w)
Heat Loss
HP Work
LP Work
CGI Energy
Stack Energy
Destruction
CGI
Brake Power
Ambient
Stack
Engine C15
A/C
LP Comp
HP Comp
LP Turb
HP Turb
DPF
CGI Cooler CGI
BrakePower
~ 34% of Exhaust availability used
~16% (throttling,
~ 34% exits stack
Recovery Method
Insulation
Bottoming Cycle
Bottoming Cycle
Turbomachinery Intercooling
Peak Torque Condition
From Cylinder Caterpillar Confidential: XXXXEngine Research
(0.5%) (0.5%) (1.3%)
High Eff.LP Turb
Compressors
ry)
ompound or Bottoming Cycleoc
Technical Approach Port Insul. PipingPoPort Insul.rt Insul. PipingPiping
(0.5%)(0.5%) IntercoolingIIntercoolingntercooling(0.5%)(0.5%) (1.(1 3%3 ). %)
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High Eff. HP Turbine (2.0%)
ine (1.0%)
(0.7%)
Stack Recove (4.0%
* Turb
High Eff.HP Turbine(2.0
High Eff.
%)HP Turbine(2.0%)
High Eff. LP Turbine(1.0%)
ineHigh Eff.LP Turb(1.0%)Compressors
(0.7%)(0Compressors
.7%)
Stack Recovery (4.0%)
StSt
* Turbocompound or Bottoming Cycle
ack Recovery(4.0%)
ack Recovery(4.0%)
* Turbocompound or Bottoming Cycle
Baseline is ’07 C15 Series Turbocharged On-Highway Truck Engine
XXXX
Nozzled / Divided Turbine vs Production
0.680
0.700
0.720
0.740
0.760
0.780
0.55 0.6 0.65 0.7 0.75 0.8
Velocity Ratio, U/C
Turb
ine-
Mec
h Ef
ficie
ncy
(%)
RND Data
Prod.Data
0.680
0.700
0.720
0.740
0.760
0.780
Accomplishments HPT +2.0%
Target: + 2.0% overall thermal efficiency ¾ Translates to ~ +10% turbine stage efficiency
Radial / Nozzled / Divided (RND) Turbine � High efficiency radial turbine wheel � Divided housing for engine breathing / pumping � Nozzled inlet for incidence control, turbine efficiency
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+5% Turbine Efficiency Demonstrated Nozzled / Divided Turbine vs Production
0.55 0.6 0.65 0.7 0.75 0.8
Velocity Ratio, U/C
Turb
ine-
Mec
h Ef
ficie
ncy
(%)
RND Data
Prod. Data
XXXX
HPT +2.0%
Target: + 2.0% overall thermal efficiency ¾ Translates to ~ +10% turbine stage efficiency
Accomplishments
Mixed Flow Turbine � High efficiency wheel designed for improved pulse utilization � Inclined volute for maximum stage efficiency � Ball Bearings for low mechanical losses
Hardware Procured, Testing Underway
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Flow Kg/s
Research Compressor
Production Compressor
Flow kg/sFlow Kg/s
Research Compressor
Production Compressor
Flow Kg/s
Target: + 0.7% overall thermal efficiency ¾ Translates to ~ +2.5% compressor stage efficiency
Accomplishments Comp. +0.7%
High Efficiency Radial Compressor � Highly backswept wheel � Low solidity vaned diffuser
0.850.80.855
0.80.0.88
0.750.70.755
0.70.0.77
0.650.60.655
0.60.0.66
0.550.50.555
+2.5-3% Compressor Efficiency Demonstrated
Research Compressor
Production Compressor
Effic
ienc
y -%
EfEffic
ienc
y -%
ficie
ncy
-%
Caterpillar Confidential: XXXXEngine Research 0.2 0.25 0.3 0.35 0.4
-– 0.0.2 0.25 0.3 0.35 0.4
-2 0.25 0.3 0.35 0.4
-Flow – kg/s
Supp.+4.0%
AdvantagesTurbocompound � Known Technology
� ‘Easy’ to package
Rankine Cycle � Cycle Efficiency � Insensitive to BP � ORC - additional fluid
Brayton Cycle � No additional fluid � Cycle Efficiency � Insensitive to BP � Packaging � Lower cost (compared
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Target: + 4.0% overall thermal efficiency
Accomplishments
Stack Recovery Methods
� Packaging / cost
Disadvantages � Sensitive to BP
Ambient
Stack
Engine C15
A/C
LP Comp
HP Comp
LP Turb
HP Turb
DPFHE
Turb CompHP Turb
DPF
Turb
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CGI
Brake Power
AmbientStack
Ambient
Stack
Engine C15
A/C
LP Comp
HP Comp
LP Turb
HP Turb
DPF
CGI
BrakePower
HE
Turb Comp
Target: + 4.0% overall thermal efficiency
AmbientAmbientStack
Accomplishments
Supp. +4.0%
Brayton
Cycle
Mechanical or electrical connection
Target: + 4.0% overall thermal efficiency
Accomplishments
Supp. +4.0%
Brayton Cycle – Engine Simulation Results � Simulated over speed load range w/ Brayton + port insul + IC
LPT comp
pipi
ng
Brayton
Insu
l.
+4%
+1.3% +0.5%
IC � Assumptions: 85% Brayton compressor 85% Brayton TurbineHPT 90% Heat Exch. Effectiveness3% Heat Exch. ΔP/P93% transmission efficiency
+5.8% Target at Design Pt. Backpressure representative of NOx A/T
plus partially loaded DPF
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1000
1500
2000
1000
1500
2000
Accomplishments Target: + 4.0% overall thermal efficiencySupp.
+4.0%
Brayton Cycle – Engine Simulation Results � Simulated over speed load range w/ Brayton + port insul + IC
30030 000
25025 000 5.8%5.8% 6.2%6.2%
Simulated Thermal Efficiency Δ
Design Point: + ~6%Drive Cycle: + 4-5%
Engi
ne L
oad
Engi
ne L
oad
4.3%4.3% 5.3%5.3%
4.0%4.0% 4.4%4.4%
500500
00500 1000 1500 2000500 1000 1500 2000Engine SpeedEngine Speed
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Target: + 4.0% overall thermal efficiency
Accomplishments
Supp.+4.0%
Brayton Cycle – Engine Simulation Results � Simulated over speed load range w/ Brayton + port insul + IC
� Assumptions: 85% Brayton compressor 85% Brayton turbine 90% Heat Exch. effectiveness
Simulated Thermal Efficiency Δ 3% Heat Exch. ΔP/P Design Point: + ~6% 93% transmission efficiency Drive Cycle: + 4-5%
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System will work if component performance targets are met
Effic
ienc
y (t/
s) @
Diff
user
Exi
t
Target: + 4.0% overall thermal efficiency
Accomplishments
Supp. +4.0%
Brayton Cycle Component Development 0.88� Compressor Wheel (85% target) 0.86 � Aero Design Complete 0.84
0.82
0.80
0.78
0.76
0.74
0.72 1.0 1.2 1.4 1.6 1.8 2.0 2.2
� Turbine Wheel (85% target) � Aero Design CompleteCaterpillar Confidential: XXXXXEngine Research
Prototype Compressor Measured Performance
1.0
1.5
2.0
2.5
3.0
3.5
4.0
0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 normalized flow
pres
sure
ratio
85%
83%
81%
Normalized Flow
Pres
sure
Rat
io
Measured Performance
27G Axial Turbine Predicted
2.4 2.6 2.8 3.0
PressRatio(t/s) @ Diffuser Exit Ef
ficie
ncy
Pressure Ratio
Predicted Performance
Target: + 4.0% overall thermal efficiency
Accomplishments
Supp. +4.0%
Brayton Cycle Component Development � Heat Exchanger (targets: 90% effective, 3% ΔP/P)
5 � Current ACPS technology: ~2ft3
Volu
me
(ft^3
) 4
3
2
1
0 80 85 90 95
Effectiveness (%)
� Unique microchannel manufacturing technology: ~1ft3
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Ongoing research to achieve further reductions
Packaging
Base EngineCaterpillar Confidential: XXXXXEngine Research
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Remote Mounting
Packaging
Base Engine On-Engine, 1ft3 H.E. On-Engine, 0.5ft3 H.E.
Foil Bearings
Summary
� Program goals can be achieved
� Path defined to achieve engine thermal efficiency of +10% at design point, + ~7% over drive cycle. Capability confirmed via engine simulation.
� Key components have been designed, analyzed, procured, and tested; component efficiencies at or close to target levels demonstrated
� Heat exchanger technology development key to packaging of system in mobile applications
� Next Steps: On-engine demonstration of advanced turbocharger technologies and design / procurement / bench-testing of Brayton cycle components
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Acknowledgements
Caterpillar Thanks:
Turbomachinery design consulting, component procurement and integration.
Turbomachinery design consulting and optimization.
Turbomachinery design consulting and optimization.
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Acknowledgements
Caterpillar Thanks:
• Department of Energy • Gurpreet Singh • John Fairbanks
• DOE National Energy Technology Laboratory• Ralph Nine
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