Research On Topology Optimization Of Liquid-cooled Heat Dissipation For Phased Array Antenna

With the development of micro-technology,electronic equipment is moving towards miniaturization.However,this trend will make the heat flux of electronic components sharply increase,the heat generated can not be timely distributed,and ultimately lead to the damage of components and shorter life.Nowadays,in order to meet the requirements of military operations,the number and power of T/R components on the array surface of phased array antenna are rising sharply.If the heat dissipation of T/R components is not good,it is very likely that the T/R components cannot work normally because of the high temperature of the array surface.Therefore,the key to improve the performance of phased array antenna is to control the temperature of array and ensure the normal operation of T/R components.In order to improve the cooling capacity of phased array antenna,many scholars at home and abroad have designed a variety of cold plate structures by using liquid cooling technology,such as traditional channel cold plate and bionic topological cold plate.However,the flow channel structure of these cold plates is based on experience.This design method has little freedom and lacks certain flexibility.In this thesis,topology optimization technology is applied to the design of cold plate structure of phased array antenna,which provides a new solution for efficient heat dissipation of phased array antenna.The specific work is as follows:(1)Taking the 4 × 6 phased array antenna T/R component as the research object,and taking the different heat source power of the antenna array as the thermal condition,it is proposed to apply the staggered multi-entry structure to the phased array antenna cold plate topology optimization structure design.In order to improve the temperature uniformity of the phased array antenna front and reduce the fluid pressure drop in the cold plate,two multi-objective functions are respectively formed by coupling the minimum temperature difference of the front,the minimum average temperature of the front and the minimum fluid dissipation power,which are used as the topology optimization objective is simulated.Finally,two topology models that meet the target requirements are obtained,and the influence of the simulation boundary condition — inlet flow on the topology results is studied.(2)The two-dimensional topological structure is stretched three-dimensionally,and the heat source temperature distribution of the three-dimensional topological model and the flow heat transfer performance of the cold plate are studied.At the same time,the traditional three-dimensional model of the channel is introduced for comparison to obtain the optimal model.The results show that under the same pump power(0.35×10-3W),the surface temperature difference of the cold plate structure designed by using topology optimization technology is reduced by 28.1%,the maximum temperature is reduced by3.2%,the thermal resistance is reduced by 25.8%,the Nusselt number is increased by36.0%,and the inlet and outlet pressure drop is lower,and the flow heat dissipation performance is better.At the same time,among the two topological models,the model aiming at the minimum temperature difference and pressure drop has the largest Nusselt number,the smallest thermal resistance,and the smallest front temperature difference,while the average temperature is similar to the numerical results of the model aiming at the minimum temperature difference and pressure drop,so its flow heat dissipation performance is optimal.(3)Using the Nusselt number as an index,the flow heat transfer stability of the optimal model under different thermal conditions is studied.The results show that the Nusselt number of the model under different thermal conditions does not differ by more than 1%,indicating that the model has a stable flow heat transfer capacity.(4)Design and build an experimental platform,conduct convective heat transfer experiments on the topology model with the best flow heat transfer performance,and analyze and compare experimental and simulation data.The results show that the temperature distribution trends of the heat source obtained by the experiment and simulation are consistent,and the maximum relative error between the pressure drop at the inlet and outlet of the cold plate and the average Nusselt number under different flow rates does not exceed 10%.Meanwhile,the uncertainty of the experimental Nusselt number is6.28%.The reliability of the liquid-cooled cold plate design using topology optimization technology and the accuracy of the numerical simulation results are further verified.