基于仿生学的热电发电装置设计、仿真与实验

Abstract Inspired by bionics, six flat plate heat collectors with leaf-shaped fins in symmetrical, staggered and alternating arrangements, based on bionics principle, along with three flat plate coolers with 2, 4 and 6 fins, were designed to enhance waste heat recovery in thermoelectric generators (TEG). Flow simulations identifies an optimized heat collector with short-long alternating elliptical fins, achieving a temperature uniformity of 0.977 and a cooler with 4 fins, achieving a velocity uniformity of 0.852. The final TEG device integrated an optimized heat collector sandwiched between the two optimized coolers, with twenty thermoelectric modules (TEMs) symmetrically arranged in two columns per side and five modules per column. The effects of hot fluid inlet temperatures on surface temperatures, heat flux density, convective heat transfer coefficients and total heat transfer coefficients across different TEM regions were simulated. The influences of parallel and counter flow arrangements on heat transfer characteristics were also analyzed. Results show that the heat transfer parameters at a constant volumetric flow rate do not monotonically increase with intake temperature due to changes in gas thermophysical properties. Compared to parallel flow, counter-flow significantly enhances convective heat transfer coefficient within the heat collector and overall heat transfer coefficient of the TEM modules. Electrical measurements under varying hot air inlet temperatures, with cooling water at 290 K, show peak output powers of 7.6 W for series-connected modules and 7.7 W for parallel-connected modules at an inlet temperature of 623 K, achieving a thermoelectric conversion efficiency of 1.43 %. The study demonstrates that optimizing fin structure and position, TEM placement, and thermal fluid parameters enhance heat transfer and improve electrical output performance.