Application Research Of Thermoacoustic Heat Transportation Characteristics For Heat Dissipation

Thermoacoustic technology is a new and reliable energy conversion technology,which can realize the mutual conversion of heat energy and sound energy(mechanical energy).Thermoacoustic refrigeration technology has shown its application potential in some fields.Still,there is room for further improvement in commercial efficiency.Besides the optimization of the structure and performance of the thermoacoustic refrigerator,it is also important to find innovative application methods to promote the commercialization of thermoacoustic refrigeration technology.Therefore,the heat transfer problem of thermoacoustic refrigerator is numerically studied as follows.(1)Aiming at the model of standing wave refrigerator,the working mode of heat dissipation of standing wave thermoacoustic engine is proposed.Delta EC software is used to simulate and analyze the heat transport characteristics of the two working modes of refrigeration and heat dissipation and the temperature distribution along the plate stack.The research shows that the heat flow direction in the cooling mode is the same as that in the cooling mode,and more heat can be transferred in the cooling mode.In this mode,the temperature difference is related to the heat transfer capacity.The higher the temperature difference is,the stronger the heat transfer capacity is.With the change of heat load temperature,the temperature distribution first increases and then decreases.The heat conduction direction in cooling mode is different from that in cooling mode,and compared with heat transfer,the heat conduction quantity is almost negligible.(2)In order to improve the performance of the standing wave refrigerator regenerator,the characteristics of sound field distribution,heat flow distribution,phase difference distribution,minimum refrigeration temperature,refrigerating capacity and COP of the regenerator were analyzed by seven layered methods.The research shows that with the decrease of refrigeration temperature,the porosity of the regenerator is increased through the stratification of the regenerator,which is beneficial to the improvement of flow loss,the effective reduction of refrigeration temperature and the improvement of refrigeration efficiency.The internal sound field distribution which is the basis of the performance calculation of the refrigerating machine is verified by the developed standing-wave refrigerating machine test bench.The stratification of the regenerator can provide an effective means for the optimization of the performance of the thermoacoustic refrigerating machine.(3)Based on the model of the traveling wave toroidal thermoacoustic engine driving refrigerator,the heat transport characteristics under refrigeration and heat dissipation mode are simulated and analyzed.The results show that in the refrigeration mode,the heat transfer,the average thermal efficiency of the unit and the COP of the unit continue to increase with the increase of the refrigeration heat load temperature.In the heat dissipation mode,the heat transfer continues to increase,and the sound power consumption gradually decreases.In the process of increasing the temperature of heat dissipation heat load,the working mode of refrigerator unit changes to that of engine.