Effect of Heat Exchanger Material and Fouling on Thermoelectric Exhaust Heat Recovery

Journal Article · Sat Jan 01 04:00:00 EST 2011 · Proceedings of the Institution of Mechanical Engineers - Part D: Journal of Automobile Engineering

OSTI ID:1027826

Love, Norman ^[1]; Szybist, James P ^[2]; Sluder, Scott ^[2]

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1. University of Texas, El Paso
2. ORNL

This study is conducted in an effort to better understand and improve the performance of thermoelectric heat recovery systems for automotive use. For this purpose an experimental investigation of thermoelectrics in contact with clean and fouled heat exchangers of different materials is performed. The thermoelectric devices are tested on a bench-scale thermoelectric heat recovery apparatus that simulates automotive exhaust. The thermoelectric apparatus consists of a series of thermoelectric generators contacting a hot-side and a cold-side heat exchanger. The thermoelectric devices are tested with two different hot-side heat exchanger materials, stainless steel and aluminum, and at a range of simulated exhaust gas flowrates (40 to 150 slpm), exhaust gas temperatures (240 C and 280 C), and coolant-side temperatures (40 C and 80 C). It is observed that for higher exhaust gas flowrates, thermoelectric power output increases while overall system efficiency decreases. Degradation of the effectiveness of the EGR-type heat exchangers over a period of driving is also simulated by exposing the heat exchangers to diesel engine exhaust under thermophoretic conditions to form a deposit layer. For the fouled EGR-type heat exchangers, power output and system efficiency is observed to be significantly lower for all conditions tested. The study found, however, that heat exchanger material is the dominant factor in the ability of the system to convert heat to electricity with thermoelectric generators. This finding is thought to be unique to the heat exchangers used for this study, and not a universal trend for all system configurations.

• Research Organization: Oak Ridge National Laboratory (ORNL); Fuels, Engines and Emissions Research Center; National Transportation Research Center
• Sponsoring Organization: ORNL LDRD Director's R&D
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 1027826
• Journal Information: Proceedings of the Institution of Mechanical Engineers - Part D: Journal of Automobile Engineering, Journal Name: Proceedings of the Institution of Mechanical Engineers - Part D: Journal of Automobile Engineering Journal Issue: 1 Vol. 89
• Country of Publication: United States
• Language: English

Related Subjects

30 DIRECT ENERGY CONVERSION
33 ADVANCED PROPULSION SYSTEMS
36 MATERIALS SCIENCE
ALUMINIUM
DIESEL ENGINES
EFFICIENCY
ELECTRICITY
FOULING
HEAT EXCHANGERS
HEAT RECOVERY
NESDPS Office of Nuclear Energy Space and Defense Power Systems
PERFORMANCE
STAINLESS STEELS
THERMOELECTRIC GENERATORS
Thermoelectric
efficiency
exhaust heat recovery