To analyze the thermoelectric power generation for sports utility vehicle (SUV) application, a novel thermoelectric generator (TEG) based on low-temperature Bi₂Te₃ thermoelectric modules (TEMs) and a chaos-shaped brass heat exchanger is constructed. The temperature distribution of the TEG is analyzed based on an experimental setup, and the temperature uniformity optimization method is performed by chipping peak off and filling valley is taken to validate the improved output power. An automobile exhaust thermoelectric generator (AETEG) using four TEGs connected thermally in parallel and electrically in series is assembled into a prototype military SUV, its temperature distribution, output voltage, output power, system efficiency, inner resistance, and backpressure is analyzed, and several important influencing factors such as vehicle speed, clamping pressure, engine coolant flow rate, and ambient temperature on its output performance are tested. Experimental results demonstrate that higher vehicle speed, larger clamping pressure, faster engine coolant flow rate and lower ambient temperature can enhance the overall output performance, but the ambient temperature and coolant flow rate are less significant. The maximum output power of AETEG is 646.26 W, the corresponding conversion efficiency is 1.03%, and the increased backpressure changes from 1681 Pa to 1807 Pa when the highest vehicle speed is 125 km/h.

The output performance of thermoelectric generator using thermoelectric modules can be improved by optimizing the heat exchanger structure, but this may cause compatibility issues in the exhaust heat recovery process, such as high backpressure and poor performance for the internal combustion engine. In this study, a polyhedral-shape heat exchanger-based thermoelectric generator system for vehicle exhaust recovery was constructed for the uniform temperature and easy thermoelectric module layout, and the influencing factors of heat transfer and backpressure was evaluated using a realizable k-ϵ turbulence model, and the influence order was analyzed based on the analysis of variance method. Finally, a multi-objective grey wolf optimizer was used to improve the thermoelectric generator system based on the proposed compatibility performance index and optimization objective function. The findings show that the heat transfer performance and backpressure of heat exchanger is obviously affected by different fin length, fin width, fin intersection angle and fin spacing distance. Compared with the empty cavity structure based one and those without optimization, the optimized fin parameters not only obtain high power and satisfactory thermoelectric conversion efficiency, but also ensure low pressure drop and ideal temperature uniformity, which well meets the compatibility requirements for automobile exhaust recovery application.

To study on the thermoelectric power generation for industrial waste heat recovery applied in a hot-air blower, an experimental thermoelectric generator (TEG) bench with the hexagonal heat exchanger and commercially available Bi₂Te₃ thermoelectric modules (TEMs) was established, and its performance was analyzed. The influences of several important influencing factors such as heat exchanger material, inlet gas temperature, backpressure, coolant temperature, clamping pressure and external load current on the output power and voltage of the TEG were comparatively tested. Experimental results show that the heat exchanger material, inlet gas temperature, clamping pressure and hot gas backpressure significantly affect the temperature distribution of the hexagonal heat exchanger, the brass hexagonal heat exchanger with lower backpressure and coolant temperature using ice water mixture enhance the temperature difference of TEMs and the overall output performance of TEG. Furthermore, compared with the flat-plate heat exchanger, the designed hexagonal heat exchanger has obvious advantages in temperature uniformity and low backpressure. When the maximum inlet gas temperature is 360 °C, the maximum hot side temperature of TEMs is 269.2 °C, the maximum clamping pressure of TEMs is 360 kg/m², the generated maximum output power of TEG is approximately 11.5 W and the corresponding system efficiency is close to 1.0%. The meaningful results provide a good guide for the system optimization of low backpressure and temperature-uniform TEG, and especially demonstrate the promising potential of using brass hexagonal heat exchanger in the automotive exhaust heat recovery without degrading the original performance of internal combustion engine.