Study On Low Temperature Cooling Dehumidification System And Its Heat Recovery Technology

It’s beneficial for the quality of either production or life to apply the reliable,economical,and efficient dehumidifying process to the humidity control of the specific places,alongside with developed energy-saving facility to recover the extra cooling-energy.Firstly in this paper,an experimental study of an air handling units with the apparatus dew point below 0 ℃ was carried out to get the combination mode,the reheating and defrosting control logic of the system.Then the mechanically pump-driven separate heat pipes were employed in the air handling units for heat recovery.To improve the defrosting performance of the system,the heat pipe and refrigerating system recombination cycle was brought up and the defrosting and working condition transforming performance of which was experimentally investigated.The experimental results have indicated that the low temperature refrigerating cycle has high COP as it’s working under heat pump mode,while the dehumidifying capacity per energy consumption of the system is higher than 4.7kg/(h · kW),showing the low energy consumption of dehumidifying;the dehumidifying capacity of the system employed with heat pipe is increased approximately by30%,and the ratio of the cooling energy recovered by heat pipe and the cooling capacity of the system reached 66%,showing the high energy-saving performance of heat pipe;Under mild,moderate,and severe frosting situation,respectively, the defrosting duration of heat pipe made up 40.4%、33.9%、30.3% to that of the hot-gas bypass defrosting,respectively.In addition,the heat source is provided by the inlet high-temperature air,and the energy consumption is extremely small.Lastly in this paper,the modeling of the flow field based on the an impeller of a magnetic pump was built and the simulation was preliminarily conducted.Difference of the numerical and experimental results was relatively small,which is instructive to the prevention of cavitation,as well as the stability of the heat pipe.In this paper,the research group inventively applied the mechanically pump-driven separate heat pipe with the low-temperature dehumidifying system to recover energy and defrost the heat exchanger,which significantly improves the dehumidifying efficiency and decreases the dehumidifying consumption.The research results are instructive for the engineering application in the dehumidifying field.