Aiming to reduce thermal energy loss at the cold side of a thermoelectric generator (TEG) module during thermoelectric conversion, a thermoelectric energy conversion system for heat recovery with a water-cooling energy exchange circuit was devised. The water-cooling energy exchange circuit realized sufficient recovery and reuse of heat accumulated at the cold side of the TEG, reduced the danger of heat accumulation, improved the stability and output capacity of thermoelectric conversion, and provided a low-cost and high-yield energy conversion strategy in energy conversion and utilization. Through the control variable method to adjust the heat generation of the heat source in the thermoelectric conversion, critical parameters (e.g., inner resistance of the TEG, temperatures of thermoelectric modules, temperature differences, output current, voltage, power, and efficiency of thermoelectric conversion) were analyzed and discussed. After using the control variable method to change the ratio of load resistance and internal resistance, the impacts of the ratio of load resistance to inner resistance of the TEG on the entire energy conversion process were elaborated. The results showed that the maximum value of output reached 397.47 mV with a current of 105.56 mA, power of 41.96 mW, and energy conversion efficiency of 1.16%. The power density of the TEG module is 26.225 W/m². The stability and practicality of the system with a water-cooling energy exchange circuit were demonstrated, providing an effective strategy for the recovery and utilization of heat energy loss in the thermoelectric conversion process.

Because the performance of giant magnetostrictive materials (GMMs) can vary at different temperatures, the positioning accuracy of a giant magnetostrictive actuator is affected by heat. In this work, a new simplified control strategy under compulsory water cooling is proposed to maintain a constant GMM temperature. Based on this strategy, a coupled turbulent flow field and temperature field finite element model is created for a GMM smart component. The model is simulated using COMSOL Multiphysics software version 5.3. Through simulations, the temperature field distribution of GMM smart components is analysed under different drive input currents and cooling water flow rates. Based on the obtained simulation results, a GMM intelligent component temperature control device is constructed. The experimental results are in good agreement with the simulation results; a thermostatic control effect is achieved in the thermostat of the giant magnetostrictive rod. Thus, the proposed temperature control strategy is proven effective via simulations and experiments.

Air-cooled finned heatsink (FHS) are more compact than water-cooled heatsink due to no water channel, which is beneficial to simplify the structure of the cooling side of the thermoelectric generator (TEG) system. Therefore, a mini channel finned heatsink (MCFHS) was designed in this study based on Venturi effect. In this study, the mathematical model of TEG with MCFHS and FHS were developed and verified. The effects of the heating temperature and air flow velocity around the heatsinks on the TEG performance were analyzed and demonstrated. The TEG performance was investigated in terms of the temperatures of the two sides of the TEG, the TEG voltage, and the TEG efficiency. The results revealed that the smaller thermal resistance of heatsink is favorable for greater output of TEG. And the use of the MCFHS can effectively improve the performance of the TEG under different conditions. The maximum TEG efficiency with MCFHS could be 155% higher than the TEG with FHS.