Experimental and parametric analysis of exhaust heat exchanger used in thermoelectric generator

Abstract

A thermoelectric generator system consists of an exhaust heat exchanger, a thermoelectric module, and water heat exchanger. Perfect heat exchangers recover as much heat energy as possible from engine exhaust with an acceptable pressure drop. The capacity and efficiency of the heat exchanger depend on its shape, type, and material of the heat exchanger. The main objective of this research was to perform a parametric analysis of the test section of the exhaust heat exchanger by using simulation tools. The simulation results were validated with the experimental results to ensure the performance of the simulation model. The performance of the test section was measured in relation to geometry, pressure drop, temperature distribution, fluid velocity, and temperature uniformity coefficient. The test section of 60 mm × 60 mm × 180 mm (F-type) shows a higher surface temperature with an allowable pressure drop than the other types of test section without inserts. The inserts played a vital role in enhancing the surface temperature distribution and uniformity coefficient. The cone type (G-type), cone-cylinder type (H-type), and cone-cylinder-cone type (I-type) inserts were used to improve the performance of the F-type test section. The G-type and H-type test sections of the exhaust heat exchanger have a high surface temperature, high-temperature uniformity, and allowable pressure drop.