Abstract

Using thermoelectric generators (TEG) to reduce exhaust heat loss from internal combustion engines can improve emissions and the fuel economy of conventional and electrified vehicles. However, TEG potentials have not been investigated in hybridized, compressed natural gas (CNG), twin-turbocharged, and spark-ignited (SI) engines. This work demonstrates TEG's effectiveness in boosting a hybridized 3.0 L CNG engine using model-based development. TEG experiments are performed to measure thermal performances under different inlet gas conditions for model validations. Simplified user-defined functions of flow friction and heat transfer coefficients are used to calibrate the model. A fast-calibration model can reproduce measured heat transfer, pressure drop, and thermal performances. The engine performances are validated against measured 35 steady-state conditions from the production engine used in light-duty CNG trucks under the JE05 drive cycle. Next, the model is connected to the turbocharging system downstream of the well-calibrated four-cylinder SI engine model. Under the peak performance condition (peak brake thermal efficiency BTE at 2400 RPM and 102 kW load), the results show that the engine BTE is improved by 0.56% using a 7 × 9 TEG module arrangement (three-sheet TEG with 1.5× A4 size). A 9 × 10 arrangement can enhance the BTE to 0.8%. Effective electrical power is generated up to 1.168 kW from the TEG, depending on the JE05 operating regions, without significant brake power loss.

References

1.
Ministry of Foreign Affairs of Japan
,
2021
, “Intended Nationally Determined Contributions (INDC): Greenhouse Gas Emission Reduction Target in FY2030”, https://www.mofa.go.jp/ic/ch/page1we_000104.html, Accessed April 2022.
2.
Japan Science and Technology Agency
, Accessed Achieving Thermal Efficiency of Over 50% in Passenger Car Engines. https://www.jst.go.jp/EN/achievements/research/bt2019–04.html, Accessed April 2022.
3.
Iida
,
N.
,
2017
, “
Research and Development of Super-Lean Burn for High Efficiency SI Engine—Challenge for Innovative Combustion Technology to Achieve 50% Thermal Efficiency
,”
Proceedings of the 9th International Conference on Modeling & Diagnostics for Advanced
,
Okayama, Japan
,
July 25–28
.
4.
Jung
,
D.
, and
Iida
,
N.
,
2017
, “
An Investigation of Multiple Spark Discharge Using Multi-Coil Ignition System for Improving Thermal Efficiency of Lean SI Engine Operation
,”
Appl. Energy
,
212
(
2
), pp.
322
332
.
5.
Sok
,
R.
,
Yamaguchi
,
K.
, and
Kusaka
,
J.
,
2021
, “
Prediction of Ultra-Lean Spark Ignition Engine Performances by Quasi-Dimensional Combustion Model With a Refined Laminar Flame Speed Correlation
,”
ASME J. Energy Resour. Technol.
,
143
(
3
), p.
032306
.
6.
Sok
,
R.
,
Kusaka
,
J.
,
Daisho
,
Y.
,
Yoshimura
,
K.
, and
Nakama
,
K.
,
2015
, “
Experiments and Simulations of a Lean-Boost Spark Ignition Engine for Thermal Efficiency Improvement
,”
SAE Int. J. Engines
,
9
(
1
), pp.
379
396
.
7.
Sok
,
R.
,
Kusaka
,
J.
,
Daishi
,
Y.
,
Yoshimura
,
K.
, and
Nakama
,
K.
,
2015
, “
Thermal Efficiency Improvement of a Lean-Boosted Spark Ignition Engine by Multidimensional Simulation With Detailed Chemical Kinetics
,”
Int. J. Automot. Eng.
,
6
(
4
), pp.
97
104
.
8.
Daisho
,
Y.
,
Miyagawa
,
K.
, and
Mihara
,
Y.
,
2019
, “
Research and Development on Utilizing Exhaust Gas Energy and Reducing Mechanical Losses by “Loss Reduction Team” in the SIP's “Innovative Combustion Technologies
,”
J. Combust. Soc. Japan
,
61
(
197
), pp.
213
223
.
9.
Kaminaga
,
T.
,
Yamaguchi
,
K.
,
Ratnak
,
S.
,
Kusaka
,
J.
,
Youso
,
T.
,
Fujikawa
,
T.
, and
Yamakawa
,
M.
,
2019
, “
A Study on Combustion Characteristics of a High Compression Ratio SI Engine With High-Pressure Gasoline Injection
,”
14th International Conference on Engines & Vehicles
,
Capri, Italy
,
Sept. 15–19
, Vol. 1.
10.
Sok
,
R.
,
Yoshimura
,
K.
,
Nakama
,
K.
, and
Kusaka
,
J.
,
2021
, “
Experimental and Numerical Analysis on the Influences of Direct Fuel Injection Into Oxygen-Depleted Environment of a Homogeneous Charge Compression Ignition Engine
,”
ASME J. Energy Resour. Technol.
,
143
(
12
), p.
122302
.
11.
Sok
,
R.
, and
Kusaka
,
J.
,
2022
, “
Experimental Investigation of Direct Fuel Injection Into Low-Oxygen Recompression Interval in a Homogenous Charge Compression Ignition Engine
,”
ASME J. Energy Resour. Technol.
,
144
(
1
), p.
012301
.
12.
Sok
,
R.
, and
Kusaka
,
J.
,
2022
, “
Fuel-Reforming Effects on a Gasoline Direct Injection Engine Under a Low-Temperature Combustion Mode: Experimental and Kinetics Analyses
,”
Energy Convers. Manage.
,
255
(
3
), p.
115304
.
13.
Chen
,
J.
, and
Wu
,
C.
,
2000
, “
Analysis on the Performance of a Thermoelectric Generator
,”
ASME J. Energy Resour. Technol.
,
122
(
2
), pp.
61
63
.
14.
Crane
,
D. T.
, and
Bell
,
L. E.
,
2009
, “
Design to Maximize Performance of a Thermoelectric Power Generator With a Dynamic Thermal Power Source
,”
ASME J. Energy Resour. Technol.
,
131
(
1
), p.
012401
.
15.
Champier
,
D.
,
2017
, “
Thermoelectric Generators: A Review of Applications
,”
Energy Convers. Manage.
,
140
(
5
), pp.
167
181
.
16.
Maduabuchi
,
C.
,
Singh
,
S.
,
Ozoegwu
,
C.
,
Njoku
,
H.
, and
Eke
,
M.
,
2022
, “
The Combined Impacts of Leg Geometry Configuration and Multi-Staging on the Exergetic Performance of Thermoelectric Modules in a Solar Thermoelectric Generator
,”
ASME J. Energy Resour. Technol.
,
144
(
4
), p.
041303
.
17.
Pang
,
D.
,
Zhang
,
A.
,
Wen
,
Z.
,
Wang
,
B.
, and
Wang
,
J.
,
2022
, “
Energy Conversion Efficiency of Thermoelectric Power Generators With Cylindrical Legs
,”
ASME J. Energy Resour. Technol.
,
144
(
3
), p.
032104
.
18.
Liu
,
T.
, and
Yang
,
Z.
,
2018
, “
Performance Assessment and Optimization of a Thermophotovoltaic Converter–Thermoelectric Generator Combined System
,”
ASME J. Energy Resour. Technol.
,
140
(
7
), p.
072010
.
19.
Buchalik
,
R.
,
Nowak
,
I.
,
Rogozinski
,
K.
, and
Nowak
,
G.
,
2020
, “
Detailed Model of a Thermoelectric Generator Performance
,”
ASME J. Energy Resour. Technol.
,
142
(
2
), p.
021601
.
20.
Amini
,
A.
,
Ekici
,
Ö
, and
Yakut
,
K.
,
2019
, “
Investigating the Effect of Medium Liquid Layer Circulation on Temperature Distribution in a Thermoelectric Generator Heat Exchanger Assembly
,”
ASME J. Energy Resour. Technol.
,
141
(
4
), p.
041902
.
21.
Schock
,
H.
,
Brereton
,
G.
,
Case
,
E.
,
D'Angelo
,
J.
,
Hogan
,
T.
,
Lyle
,
M.
,
Maloney
,
R.
, et al
,
2013
, “
Prospects for Implementation of Thermoelectric Generators as Waste Heat Recovery Systems in Class 8 Truck Applications
,”
ASME J. Energy Resour. Technol.
,
135
(
2
), p.
022001
.
22.
Hussain
,
Q.
,
Brigham
,
D.
, and
Maranville
,
C.
,
2009
, “
Thermoelectric Exhaust Heat Recovery for Hybrid Vehicles
,”
SAE Int. J. Engines
,
2
(
1
), pp.
1132
1142
.
23.
Kempf
,
N.
, and
Zhang
,
N.
,
2016
, “
Design and Optimization of Automotive Thermoelectric Generators for Maximum Fuel Efficiency Improvement
,”
Energy Convers. Manage.
,
121
(
8
), pp.
224
231
.
24.
Ran
,
Y.
,
Deng
,
Y.
,
Hu
,
T.
,
Su
,
C.
, and
Liu
,
X.
,
2018
, “
Energy Efficient Thermoelectric Generator-Powered Localized Air-Conditioning System Applied in a Heavy-Duty Vehicle
,”
ASME J. Energy Resour. Technol.
,
140
(
7
), p.
072007
.
25.
Kim
,
T. Y.
,
Kwak
,
J.
, and
Kim
,
B.
,
2019
, “
Application of Compact Thermoelectric Generator to Hybrid Electric Vehicle Engine Operating Under Real Vehicle Operating Conditions
,”
Energy Convers. Manage.
,
201
(
12
), p.
112150
.
26.
Quan
,
R.
,
Yue
,
Y.
,
Huang
,
Z.
,
Chang
,
Y.
, and
Deng
,
Y.
,
2022
, “
Effects of Backpressure on the Performance of Internal Combustion Engine and Automobile Exhaust Thermoelectric Generator
,”
ASME J. Energy Resour. Technol.
,
144
(
9
), p.
092301
.
27.
Sok
,
R.
, and
Kusaka
,
J.
,
2023
, “
Experimental and Modeling Analysis on Thermoelectric Heat Recovery to Maximize the Performance of Next-Generation Diesel Engines Dedicated for Future Electrified Powertrains
,”
Appl. Therm. Eng.
,
219B
(
1
), p.
119530
.
28.
Allison D
,
O.
,
1972
,
Polynomial Approximations of Thermodynamic Properties of Arbitrary Gas Mixtures Over Wide Pressure and Density Ranges
,
NASA Technical Note
,
Hampton, VA
,
23365
. https://ntrs.nasa.gov/citations/19720021272
29.
Sok
,
R.
,
Kusaka
,
J.
,
Nakashima
,
H.
, and
Akaike
,
M.
,
2021
, “
A Modeling Study on Fuel Consumption Improvement of a Light-Duty CNG Truck Equipped With a Hybrid Powertrain
,”
Proceedings of the 5-6th Thermal and Fluids Engineering Conference
,
Virtual
,
May 26–28
.
30.
White
,
F. M.
,
1986
,
Fluid Mechanics
, 2nd ed.,
McGraw Hill
,
London, UK
.
31.
Cruz
,
D. A.
,
Coelho
,
P. M.
, and
Alves
,
M. A.
,
2012
, “
A Simplified Method for Calculating Heat Transfer Coefficients and Friction Factors in Laminar Pipe Flow of Non-Newtonian Fluids
,”
ASME J. Heat and Mass Transfer
,
134
(
9
), p.
091703
.
32.
Nikuradse
,
J.
,
Strömungsgesetze in rauhen Rohren
,
2013
, VDI-Forschungsheft 361. Beilage zu “Forschung auf dem Gebiete des Ingenieurwesens” Ausgabe B Band 4, July/August 1933.
33.
GT-Suite
,
2021
,
User Manual
,
Gamma Technologies LLC
,
IL, USA
.
34.
Swamee
,
P. K.
, and
Jain
,
A. K.
,
1976
, “
Explicit Equations for Pipe-Flow Problems
,”
J. Hydraul. Div.
,
102
(
5
), pp.
657
664
.
35.
Fogla
,
N.
,
Bybee
,
M.
,
Mirzaeian
,
M.
, and
Millo
,
F.
,
2017
, “
Development of a K-k-∊ Phenomenological Model to Predict In-Cylinder Turbulence
,”
SAE Int. J. Engines
,
10
(
2
), pp.
562
575
.
36.
Sok
,
R.
,
Yamaguchi
,
K.
, and
Kusaka
,
J.
,
2019
, “
0D/1D Turbulent Combustion Model Assessment From an Ultra-Lean Spark Ignition Engine
,”
SAE Technical Paper 2019-01-1409
.
37.
Sok
,
R.
,
Takeuchi
,
K.
,
Yamaguchi
,
K.
, and
Kusaka
,
J.
,
2020
, “
Numerical Methods on VVA and VCR Concepts for Fuel Economy Improvement of a Commercial CNG Truck
,”
SAE Technical Paper 2020-01-2083
.
38.
Sok
,
R.
,
Kataoka
,
H.
,
Kusaka
,
J.
,
Miyoshi
,
A.
, and
Reitz
,
R. D.
,
2023
, “
A Novel Laminar Flame Speed Equation for Quasi-Dimensional Combustion Model Refinement in Advanced, Ultra-Lean Gasoline Spark-Ignited Engines
,”
Fuel
,
333
(
2
), p.
126508
.
39.
Sok
,
R.
, and
Kusaka
,
J.
,
2023
, “
Development and Validation of Thermal Performances in a Novel Thermoelectric Generator Model for Automotive Waste Heat Recovery Systems
,”
Int. J. Heat Mass Transfer
,
202
(
3
), p.
123718
.
40.
Dong
,
J.
,
Chen
,
J.
,
Chen
,
Z.
,
Zhang
,
W.
, and
Zhou
,
Y.
,
2006
, “
Heat Transfer and Pressure Drop Correlations for the Multi-Louvered Fin Compact Heat Exchangers
,”
Energy Convers. Manage.
,
48
(
5
), pp.
1506
1515
.
41.
Jeon
,
C. D.
, and
Lee
,
J.
,
2001
, “
Local Heat Transfer Characteristics of Louvered Plate Fin Surfaces
,”
Proceedings of the ASHRAE 2001 Winter Meeting CD, Technical and Symposium Papers
,
Atlanta, GA
,
Jan. 1
, pp.
1075
1082
.
42.
Yamagishi
,
T.
,
Shingyouchi
,
H.
,
Yamaguchi
,
K.
,
Mizushima
,
N.
,
Noyori
,
T.
,
Kusaka
,
J.
,
Okajima
,
T.
,
Sok
,
R.
, and
Nagata
,
M.
,
2021
, “
A Novel Integrated Series Hybrid Electric Vehicle Model Reveals Possibilities for Reducing Fuel Consumption and Improving Exhaust Gas Purification Performance
,”
SAE Technical Paper 2021-01-1244
.
You do not currently have access to this content.