The step-change cooling performance of miniature thermoelectric module for pulse laser

Abstract

This article investigates a miniature thermoelectric module (MTEM) for pulse laser cooling. A step-changed cooling model is developed to predict the thermal performance of the MTEM. Interfacial effects of the MTEM are analyzed by considering the thermal non-equilibrium between electrons and phonons adjacent to thermoelectric/metal interface. Parametric studies were performed to analyze the effect of the pulse-width of laser, thermal resistance of hot-end heat exchanger, cooling load and the step-changed voltage on the system cooling performance. Particular attention is paid to the influence of scaling effect and supercooling effect on enhancing the miniature thermoelectric cooling (MTEC) performance. At a specific cooling load, the effects of pulse-changed and step-changed voltage on MTEC are numerically and experimentally studied. The MTEM can deal with not only the low cooling load of continuous laser, but also high cooling load of pulse laser which surpasses its’ maximum cooling capacity. The transient response of cold-end temperature experiences an underdamped oscillation and finally reaching a steady-state value. A curve fitting equation for cold-end temperature is used to provide more accurate temperature and understand the temperature control strategy for pulse laser. The numerical result shows that the prediction by the model agrees well with the performance curve of datasheet and experimental data. It is also found that the voltage for achieving the maximum cooling capacity experiences step decrease with the increase of thermal resistance of hot-end heat exchanger.