Numerical Simulation Of Velocity Field And Temperature Field Of Heat Sink In Vacuum Environment Simulator

The main function of the space environment simulator is to simulate the harsh environment such as the vacuum,cold and dark in the experiment on the ground.The high technology of heat sink development determines the accuracy of the space environment provided by the space environment simulator,and affects the test and research of spacecraft or satellite on the ground.As the main component of the space environment simulator,the heat sink is the main component of providing the low temperature environment for the space environment simulator.The uniformity of temperature is the first prerequisite to ensure In the thermal experiment.In this paper,the main research objective is to study the velocity and temperature field of heat sink.And discussing the relationship between the velocity distribution and temperature distribution in the heat sink.By changing the influencing factors of heat sink,the corresponding changes of heat sink velocity field and temperature field were analyzed.Summarizing the influence law of influencing factors and obtaining the optimal design parameters.Therefore,The feasible Suggestions for improving the temperature uniformity of heat sink are put forward.Besides,on the premise of uniform temperature distribution and good velocity distribution of heat sink,the cooling rate of heat sink is obtained,and the dynamic reaction performance of heat sink is evaluated,providing theoretical basis for heat sink design and improving the performance of heat sink.In this paper,numerical simulation of heat sink is conducted based on CFD.First,the velocity field of tube-plate heat sink was numerically analyzed in liquid nitrogen and gas nitrogen.The effects of inlet velocity and branch pipe diameter of different refrigerant carriers on heat sink pressure and velocity were analyzed.Then,the temperature field of the heat sink pipe is simulated numerically.The influence of different velocity of coolant carrier,width of radiator-fan and branch pipe diameter on the temperature distribution of heat sink in single branch pipe and the cooling rate of heat sink in unsteady state were analyzed.Finally,the conclusion of numerical simulation is given based on the above two parts.The simulation study in this paper shows that for the velocity field distribution of heat sink skeleton,changing the inlet velocity has little effect on the uniformity of velocity distribution of heat sink,and the velocity in the heat sink skeleton will increase as a whole.Changing the diameter of the branch pipe has an obvious influence on the velocity distribution in the branch pipe.The smaller the diameter of the branch pipe,the less uneven the velocity distribution will be.For the distribution of the temperature field of heat sink,increasing the flow velocity of coolant carrier in the branch pipe of heat sink can increase the heat transfer coefficient between the coolant carrier and the inner wall of the pipe and improve the thermal uniformity of heat sink.By reducing the width of heat sink radiator-fan,the absorption area of heat sink to heat radiation is reduced,the heating load of each branch pipe is reduced,and the heat uniformity of heat sink is better.Increasing the thickness of heat sink radiator-fan has little effect on the thermal uniformity of heat sink.However,if the fin thickness is too thin,the heat transfer effect of the fin will be very poor,and the structural strength of the heat sink will also be poor,affecting the normal operation of the heat sink.And,if the fin thickness is too thick,the heat transfer performance will be slightly enhanced,but the heat sink structure is relatively heavy and the cost will increase.The thermal uniformity of heat sink can be improved by increasing the diameter of heat sink branch pipe,but it also increases the amount of refrigerant carrier,which increases the cost of heat sink operation.In addition,the unsteady numerical simulation of the temperature field of the heat sink single branch pipe is carried out in this paper,and the cooling rate and trend of the heat sink single branch pipe are obtained.The cooling rate of the heat sink conforms to the design regulations of the heat sink.