Parametric study of a thermoelectric generator system for exhaust gas energy recovery in diesel road freight transportation. (1st February 2017)

• Record Type: Journal Article
• Authors: Vale, S.; Heber, L.; Coelho, P.J.; Silva, C.M.
• Is Part Of: Energy conversion and management. Volume 133(2017)
• Page Start: 167
• Page End: 177
• Publication Date: 2017-02-01
• Subjects: Energy recovery -- Thermoelectric generator -- Exhaust gas heat transfer -- Diesel vehicles for freight transport; Direct energy conversion -- Periodicals; Energy storage -- Periodicals; Energy transfer -- Periodicals; Énergie -- Conversion directe -- Périodiques; Direct energy conversion; Periodicals; 621.3105
• DOI: 10.1016/j.enconman.2016.11.064
• Languages: English
• ISSNs: 0196-8904

Abstract

Highlights: 1-D numerical TEG model in diesel freight vehicles exhaust pipe. Over 800 W of electrical power for the heavy-duty vehicle. Plain fins provide better performance than offset strip fins. The height of the thermocouple legs plays a significant role. 2% maximum efficiency needs further improvements. Abstract: A parametric study and optimization approaches of a thermoelectric generator (TEG) for the recovery of energy from the exhaust gas in Diesel vehicles used in freight transport is reported. The TEG is installed in the tailpipe of a commercial vehicle (3.5 tonnes) and a heavy-duty vehicle (40 tonnes). The exhaust gas is used as the heat source and the cooling water as the heat sink. Two different heat exchanger configurations are considered: plain fins and offset strip fins. The influence of the height, length and spacing of the fins on the electrical and net power is analysed for the fixed width and length of the TEG. The influence of the length and width of the TEG and of the height of the thermocouple legs is also investigated. According to the criteria used in this study, plain fins are the best choice, yielding a maximum electrical power of 188 W for the commercial vehicle and 886 W for the heavy-duty vehicle. The best recovery efficiency is about 2%, with an average thermoelectric material efficiency of approximately 4.4%, for the light-duty vehicle. Accordingly, there is significant room for further improvement and optimisation based on the thermoelectric modules and the system design.