Numerical Investigation of Thermoelectric Generator for Waste Heat Recovery of Diesel Engine

Abstract

Thermoelectric generators hold immense promise in addressing the ever-increasing global energy demands and environmental concerns. Harnessing waste heat from various sources, such as exhaust gases from internal combustion engines, represents a vital avenue for improving energy efficiency and reducing emissions. In light of this, the present study introduces a comprehensive model for evaluating the performance of thermoelectric generators in heat recovery from diesel engine exhaust, shedding light on the potential of this technology to contribute to sustainable energy solutions. In this study, a model is presented for evaluating a thermoelectric generator's performance in heat recovery. The model is validated using experimental data from the literature. In this setup, 14 thermoelectric modules are placed at both the bottom and top of a rectangular gas channel of a diesel engine to recover heat from the exhaust gas. The hot head is heated by the exhaust gas, while the cold head is cooled by water, maintaining a constant temperature of 293 K. However, the temperature of the hot head varies depending on the engine's speed and load. The study investigates 12 different engine operating modes, including three motor speed modes (1000, 1500, and 2000 rpm) and five motor load modes (0.2, 0.4, 0.6, 0.8, and 1.0 MPa). Numerical analysis is performed concurrently with finite element simulations. The numerical and experimental finite element results are compared, and the findings confirm the consistency of the results.