Experimental Analysis And Optimization Of Vehicle-mounted Refrigerator Based On Thermoelectric Cooling

In recent years,thermoelectric refrigeration is regarded as a promising method of refrigeration or heating.With the increase of the number of cars per capita,the number of vehicle-mounted refrigerators is increasing.Vehicle-mounted thermoelectric refrigerator has become a new favorite of the automobile industry because of its advantages such as clean and pollution-free,compact structure,reliable performance and long service life.Therefore,it is of great value for human and industrial application to explore the refrigeration characteristics and influencing factors of vehicle-mounted thermoelectric refrigerator.In this paper,the refrigeration principle of the vehicle-mounted thermoelectric refrigerator is introduced,the experimental bench is built,the theoretical refrigeration performance of the thermoelectric refrigerator is made,and under the condition of multi-objective constraints,the parameters that affect the refrigeration performance of the vehicle-mounted thermoelectric refrigerator are experimentally analyzed,and the refrigeration performance is obtained.Also,SolidWorks flow simulation software is used to optimize the structure of the thermoelectric refrigerator and the inner wall of the box.The main conclusions are as follows:1)When the cooling mode of the hot end of the thermoelectric refrigerator is air cooling,circulating water cooling and heat pipe cooling,the experimental test system is stable in 8 minutes,12 minutes and 15minutes respectively.When the temperature is stable,the difference between the average temperature in the box and the outdoor temperature is8.5℃,9.5℃and 13.5℃,respectively.2)The influence of volume,velocity,working medium and non-circulating water velocity of circulating water on the refrigeration performance of thermoelectric refrigerator is analyzed.It is concluded that the experimental system is stable in 12 minutes and has nothing to do with the volume and velocity of water.3)The results show that the temperature difference of inside and outside of the box increases with the increase of the working voltage of the thermoelectric module(within the rated range),and finally tends to be flat.4)The influence of the number of thermoelectric modules on the refrigeration capacity is studied.The results show that:when the heat dissipation capacity of the hot end is enough,the more the number of thermal modules,the lower the temperature in the box,the better the temperature uniformity;the cooling capacity Q_C of the thermoelectric module,the temperature difference between the hot and cold ends,the heat power introduced into the thermoelectric box and the cooling power that the internal radiator of the box cannot derive increase with the number of thermal modules;the cooling coefficient COP_C,decreases with the number of thermal modules.5)The results show that when designing the thermoelectric refrigerator,the cold end of the refrigerator should increase the fluid contact area with the refrigerator as much as possible,and the temperature in the refrigerator is the lowest;there is a gap between the refrigeration assembly and the box wall,and when the fan blows against the radiator at the cold end of the thermoelectric module,the temperature in the refrigeration box is the lowest and the refrigeration effect is the best.6)The size of the slot between the refrigeration assembly and the wall of the thermoelectric refrigeration box is simulated and optimized.The results show that the temperature in the box is the lowest and the refrigeration effect is the best when the size of the slot around the refrigeration body is 41.7 mm×41.7 mm×20 mm.The average temperature curve of the box under different slot sizes is given.7)The simulation and optimization of the support frame in the slot between the refrigeration assembly and the wall of the thermoelectric refrigeration box are carried out.The results show that the support frame should meet the requirements of symmetrical structure,circular hollowing on four sides,and the hollowing should be as large as possible and not exceed the frame.At this time,the temperature in the box is the lowest,and the refrigeration effect of the refrigeration box is the best.