Study On Heat Transfer And Flow Performance Of Multiple Parallel Flow Heat Exchanger With Small Temperature Difference Of Heat Transfer

Under the conditions of the small temperature difference of heat transfer and high density of heat flux, separated type heat pipe system with auxiliary power is designed for the purpose of electronic equipment heat dissipation, which can run reliably and saving energy. Circulate power of the system comes from a shielding pump, the latent heat from refrigerant’s phase change is used for heat dissipation. Multiple parallel flow heat exchangers which have high thermal efficiency and compact structure are used as condensers and some evaporators in order to satisfy the heat dissipation.This paper mainly studies on the characteristics of flow and heat transfer of parallel flow heat exchanger which has a high density of heat flux and small temperature difference of heat transfer. According to the characteristics of the system operating conditions, system scheme is confirmed after comparison. Multiple parallel flow heat exchangers are designed based on the principles of high speed of head-on wind, suitable fin coefficient and process distribution, then assembled the prototype and studied it through experiment combined with numerical simulation.The results shows:(1) The COP of the separated type heat pipe with high heat transfer efficiency parallel flow heat exchanger is over10.(2) The heat transfer performance and refrigerant’s flow resistance of parallel flow heat exchanger are both decreasing when environmental temperature is rising, these two conditions should be balanced in a design work for the purpose of satisfy the request of both heat transfer performance and refrigerant’s flow resistance.(3) There is a suitable scope for refrigerant flow of a heat exchanger, and its heat transfer performance will have a significant reduction when refrigerant flow is beyond the scope.(4) The separated type heat pipe with parallel flow heat exchanger has a quick response, system’s time constant is around5minutes, and it is good for keep object’s temperature stable. Based on the above analyses, the parallel flow heat exchanger’s design principles show satisfactory results under the conditions of small temperature difference of heat transfer and high density of heat flux.