Analysis And Study On Cooling Performance Of Single-Stage Thermoelectric Cooling Devices

With the figure of merit of thermoelectric material increase, thermoelectric refrigeration has been widely used in military, aerospace, medical, microelectronics precision for rapid cooling or high-accuracy temperature control. Comparing with vapor compression refrigeration, thermoelectric refrigeration is pollution-free, low noise, high reliability and easily integrated, etc., but Its cooling performance is pretty low, usually with COP of 0.2-0.6 for a single-stage thermoelectric cooler(TEC), far below the vapor compression refrigeration's COP, Which make it impossible to compete with vapor compression refrigeration in civilian areas. So the improvement of the performance of TEC is of great significance to broaden its application areas and helpful for the development of the TEC.To improve the performance of TEC, firstly we need to determine the influencing factors of the performance of TEC. In this paper, mathematical model of a single-stage thermoelectric cooler is developed, according to the mathematical model, analytical solutions for Qc and COP are derived in the steady-state conditions. Comprehensive analysis of the parameters (current, resistance, geometirc factor, number of thermocouples in a TE module) on the performance of TEC device is done. Main influencing parameters on the performance of TEC device is identified and the range of each parameter for a optimal COP is given under a certain design condition.Then an one-dimensional simulation model of thermoelectric refrigerator(TER) is established and numerical simulation on transient thermal behavior of a thermoelectric refrigerator under different power inputs is developed using the finite differences method. Based on the numerical simulation , transient cooling performance of a 20L thermoelectric refrigerator is tested. Results show that there are good agreements between numerical simulation and experiments. Then the transient temperature changes of the cold and hot junctions of the thermoelectric module under increasing or decreasing power supply are discussed through both simulation and experiments.This study shows that the performance of TEC is determined by multiple parameters, and the parameters for optimal COP vary with different design conditions. But they can refer to this study to determine its value. Meanwhile the author proposes an idea of transient cooling by incremental power supply. This study has a certain significance on the thermoelectric cooler and module design.