Technological watch

Waste heat recovery of diesel engine using porous medium-assisted thermoelectric generator equipped with customized thermoelectric modules

In this study, thirty of customized bismuth-telluride (Bi2Te3) thermoelectric modules (TEMs) were fabricated for waste heat recovery of a diesel engine using a thermoelectric generator (TEG). By installing a plate-type porous medium whose porosity ranges from 0.121 to 0.516 in the TEG, the effects of the porosity on energy harvesting performance were investigated. Experimental results show that at the highest engine rotation speed of 1400?rpm, a maximum power output of 98.3?W was obtained using the lowest porosity (0.121), and a maximum energy conversion efficiency of 2.83% was obtained using the optimal porosity (0.416). The most significant improvements in the power output and conversion efficiency compared with the base case without porous media were 44.5% and 10.1% with porosities of 0.121 and 0.416, respectively, at the lowest engine speed of 1000?rpm. We concluded that the conversion efficiency and power output of the present TEG can be maximized via application of porous media with porosities of 0.461 and 0.32, respectively. The use of a porous medium with a porosity of <0.32 in the present TEG configuration should be avoided, as the backpressure would exceed the allowable limit of ~3?kPa for a passenger vehicle.

Publication date: 01/10/2019

Author: Young Choi, Assmelash Negash, Tae Young Kim

Energy Conversion and Management

This project has been co-funded with the support of the LIFE financial instrument of the European Union [LIFE17 ENV/ES/000438] Life programme

The website reflects only the author's view. The Commission is not responsible for any use thay may be made of the information it contains.
Last update: 2019-05-09