An Study On Transient Supercooling Characteristic Of Thermoelectric Cooler Under A Pulse Voltage

Following the decreasing size and increasing power consuming of the electronic components,the cooling performance is confronted of great challenges that conventional heat dissipating technologies can no more full-fill the demands.Thermoelectric coolers have attracted a great deal of attention because of its small size,no pollution,wide cooling range and high reliability.In this paper,the steady-state and transient super-cooling characteristics of thermoelectric refrigeration are analyzed experimentally and numerically.The results of the study provide a reference for the application of thermoelectric refrigeration technology.The main research work and the results are as follows:(1)In this paper,the basic characteristics of the thermoelectric cooler are analyzed,and the influence of the Thomson effect on the refrigeration performance is discussed.The results show that the Thomson effect can improve the cooling capacity and COP of the thermoelectric cooler to a certain extent.(2)Based on the basic theory,the influence of the parameters such as the working voltage,the cold junction load and the heat transfer intensity at the hot end on the thermoelectric refrigeration performance was studied by experimental method.The experimental results show that the cooling performance of the thermoelectric cooler is closely related to the working voltage,and the optimum operating voltage is obtained for different heat transfer coefficient and cold end load,so that the refrigeration performance is optimal.The optimal working voltage is 9V with air cooling on the hot end,while it is 12 V with water cooling.(3)The influence of pulse voltage amplitude,pulse time and cold side load on transient super-cooling effect was discussed experimentally.The experimental results show that,when the impulse voltage signal that is several times than the reference voltage is applied to the thermoelectric module,the transient super-cooling effect is generated.The optimal pulse amplitude and the pulse time are different for different reference voltages.In addition,when the pulse voltage periodically changes,the cold end temperature is also a certain range of cyclical fluctuations,the longer the pulse period,the cyclical transient super-cooling effect is better.(4)This paper also establishes a model of thermoelectric refrigeration transient change,which takes into account the influence of Thomson effect.The finite difference method is used to calculate the model,and the influence of pulse waveform on transient undercooling is also analyzed.The results show that the minimum super-cooling time of the pulse voltage of the square wave waveform is the shortest,and a good transient super-cooling effect can be obtained at the beginning of the pulse,and the transient super-cooling effect of the triangular waveform is optimal in the whole pulse time.