Investigation of the coupling mechanism between structural parameters of thermoelectric coolers and heat sink thermal resistance

Current research on thermoelectric cooler (TEC) hot-end heat dissipation primarily focuses on enhancing cooling performance by reducing heat sink thermal resistance (Rh). However, some evidence suggests complex interactions exist between TEC structural parameters and heat sink thermal resistance, necessitating in-depth investigation into their intrinsic relationship to guide TEC structural optimization design. This study established a dynamic coupling model of thermal resistance and structural parameters, incorporating the heat sink thermal resistance as a key variable. Through integrating mathematical modeling, simulation analysis, and the response surface methodology, we discovered that the influence significance of thermoelectric leg dimensions on both cooling performance and thermal stress exhibits significant variations under different Rh conditions. Taking the maximum cooling capacity (Qcmax) as an example, at Rh = 0.1 K/W, reducing the thermoelectric leg height from 1.57 mm to 0.57 mm increases Qcmax by 29.322 W. At Rh = 1 K/W, however, Qcmax increases by only 1.664 W. This study revealed the non-uniform correlation among TEC structural parameters, heat dissipation conditions, and performance/stress. Such heterogeneity originates from a shift in dominant influencing mechanisms under varying thermal resistance conditions. Through comparative analysis, the research elucidated its intrinsic mechanism. This study offers a more comprehensive optimization perspective in this field, providing the theoretical basis for reducing TEC design costs and improving design effectiveness.