Simulation Analysis And Experimental Investigation Of Efficient And Compact Phase Change Heat Storage Heat Exchanger

As electronic components are gradually moving toward integration and miniaturization,their structures are becoming more compact and the thermal load generated is gradually increasing.The temperature control and temperature reduction of electronic components have gradually become a widespread concern in the fields of aerospace and Internet big data.Aiming at the problem of temperature instability in high heat density electronic component systems,phase change heat storage materials absorb a large amount of heat through melting to reduce the influence of temperature changes on the standard operating conditions of t he whole system,thereby effectively reducing the risk of system operation.The phase change material has high heat storage density and strong performance stability,and is suitable for the rapid cooling of heat load fluids and the maintenance of system temperature stability.In this paper,a compact phase change heat storage heat exchanger is developed based on a special heat dissipation requirement.Using n-tetradecane with a phase transition temperature of about 5.5 °C as a phase change material,and the internal heat storage unit uses a phase change microcapsule-like aluminum alloy tube to encapsulate the phase change heat storage medium.Each phase change heat storage unit is arranged in order,and the heat load fluid flows through the gap between the outer tube walls.Each phase change heat storage unit is arranged in sequence,and the heat load fluid flows through the gap between the outer tube walls,and the size of the phase change heat storage heat exchanger is designed by calculation.The best design is achieved.The average outlet temperature of the solution is 11.1 °C,and the maximum differential pressure between the inlet and outlet is 0.14 bar.The phase change heat storage heat exchanger has the advantages of low cost,high reliability,no influence by gravity,convenient installation,light weight and no pollution.The performance parameters such as the outlet temperature,inlet and outlet pressure difference,internal n-tetradecene melting rate and the outlet temperature of the phase change heat storage heat exchanger were studied by numerical simulation.The heat dissipation structure of the heat exchanger was designed and the heat dissipation effect was studied.The heat transfer performance of the phase change heat storage heat exchanger was studied through experiments.The test platform was built to study the changes of the outlet temperature and the pressure difference between the inlet and outlet of the phase change heat storage heat exchanger under different working conditions.The temperature difference between the average temperature of the heat exchanger outlet and the inlet temperature is reduced by more than 10.0 °C,and when the flow rate is 30 L/min and the inlet temperature is 25 °C,the average outlet temperature is 11.9 °C.The experimental results show that compared with the increase of the inlet flow rate,the increase of the inlet temperature has a more significant effect on the temperature difference between the average temperature of the outlet and the inlet temperature.Comparing the average temperature of the outlet of the phase change heat storage heat exchanger and the inlet and outlet pressure difference of numerical simulation and experimental results.By comparing the flow change of the phase change heat storage heat exchanger with the influence of the inlet temperature change on the performance parameters,it is found that the flow change has a great influence on the pressure difference between the inlet and outlet,and the change of the inlet temperature has a great influence on the average temperature of the outlet.The comparison results prove the correctness of the model simplification and complete the calibration of the numerical model,which provides a reference for the further optimization of the subsequent phase change heat storage heat exchanger.