| With the function and scale of large spacecraft like manned spacecraft or spacestation unceasingly expand, the heat generated by internal electronic equipment ordevices is increasing, and high heat flux in some locations becomes common.Utilizing the traditional single phase fluid circuit for heat dissipation will lead to largesize and mass of thermal control system, and it is difficult to control heat flux ortemperature to a certain level accurately. While vapor compression heat pump canimprove the radiation temperature by means of improving the condensing temperaturethrough compressor, so as to reduce the area and weight of radiator obviously,therefore it has great potential application.According to the requirement of application in cooperation with a space project,a miniature100W heat pump system for chip cooling in satellite is designed and built.It mainly consists of a rotary compressor produced by American aspen company, twomicro-channel phase change heat sinks served as evaporator, and some othercomponents. For there exists two heat sources in practical application, the two groupsof heat sinks in heat pump system are connected respectively in parallel and series forrelated research.In the heat pump system with two heat sinks in parallel, heat load is fixed as100W, the impact of refrigerant charge, capillary length, cooling water temperatureand the compressor speed on the cooling effect of heat sink and performance of thesystem are studied respectively. The results show that: the optimal refrigerant chargeis120g, the appropriate length of capillary is3m, the system can exhaust more than100watt heat just at compressor’s lowest speed, compressor power≤50W, COP≥3.In the condition that evaporating temperature is about12℃and condensingtemperature is43.6℃, the system can maintain the two heat sink’s temperature at20℃when heat load is less than140W, and40℃when heat load is less than180W.In the heat pump system with two heat sinks in series, the optimal refrigerantcharge is tested, the ability of thermal control and refrigeration characteristics arestudied when the heating power on the two heat sinks is inconsistent. Finally theperformance of heat pump is also studied when the cooling load is more than100W. Itis found that temperature of the two heat sinks can be cooled to12℃and kept steadywhen cooling load is100W, but when load exceeds140W the temperature of thesecond heat sink won’t descend.Finally, the experiment results of the two different heat pump system aresummarized, characteristics and differences of them are analyzed. |
