Maximising thermoelectric cooling performance through optimal leg geometry and phase change materials adopted heat sink configuration.

As electronic devices continue to shrink, the issue of heating in electronic circuit components has become more prominent. Thermoelectric (TE) coolers have emerged as a solution to these problems, thanks to their scalability, silent operation for thousands of hours, and precise temperature control. While the thermoelectric properties of TE elements are crucial for the cooling performance of TE coolers, other factors, such as the leg geometry, heat sink parameters, and air velocity rate, also significantly impact performance. This paper presents a numerical study on the cooling performance of two-leg TE coolers with equal volumes but differing in four-leg geometries: rectangular, cylindrical, frustum prism, and frustum cone. The investigation considered an electric current, heat sink parameters, and air velocity. It was observed that the cooling performance of the frustum cone and frustum prism structures is superior to that of the cylindrical and rectangular structures. In terms of heat sink parameters, increasing the fin count, length, height, and thickness, along with air velocity, enhances superficial heat transfer. Simulation results concluded that for optimal cooling performance, the leg geometry should be conical, the applied current should be 0.5 A, the air velocity should be 3 m/s, and the heat sink should have eight fins with a thickness of 0.6 mm, a height of 8 mm, and a length of 4 mm. Moreover, passive PCM cooling can be a viable substitute for free air cooling, delivering consistent temperature management over time, which is particularly useful in instances where TEC is used for short periods or in confined spaces without available free air, such as compact electronics.