| In this paper,the performance of a small LiBr absorption chiller and its practical application were studied.First,a 10kW small effect single LiBr absorption refrigeration air-conditioning system was set up,and the performance of the chiller was experimentally studied combined with fan coil,capillary mat radiation ceiling and displacement ventilation,capillary mat radiation ceiling,respectively.For the terminal of fan coil and capillary mat radiation ceiling alone,hot water go back to the tank after using in the LiBr absorption chiller and the chilled water from chiller is let into the terminal directly.For the terminal of capillary mat radiation ceiling combined with displacement ventilation,after hot water is used for the heat source of LiBr absorption chiller,the discharged water is driven into the rotary dehumidifier and used for the heat source of regeneration air;and the chilled water generated by LiBr absorption chiller is first used for the cold source of rotary dehumidifier and then driven into capillary mat ceiling for cooling radiation.Then,for the three different types of air conditioning terminals,the system performances were tested under different hot water temperatures and flow rates,different cooling water flow rates and chilled flow rates.The optimum temperature and flow rate of hot water,flow rate of cooling water and cold water were obtained,the relative best condition of each terminal were found,and the system operating characteristics were analyzed when chiller worked under the relative best condition.The results show that the system design of capillary mat radiation ceiling and displacement ventilation is feasible.The chiller has the highest cooling capacity and COP,the lowest temperature in the air-conditioned room and no dew condensation on the surface of the suspended ceiling when using capillary network alone because of higher temperature of suspended ceiling surface dew point temperature of inndoor air,so the system performance is optimal when the small LiBr absorption chiller with capillary network.In addition,ultrasonic waves are applied to the chiller.The results show that:compared with the unused ultrasonic,the outlet temperature of the refrigerant water decreased significantly by 6.4%on average while the cooling capacity of the chiller unit increased by an average of 8.8%,and the COP increased by an average of 13.3%.Considering ultrasonic enhanced heat transfer and ultrasonic enhanced mass transfer,it is concluded that the cavitation effect,mechanical effect of ultrasonic wave and vacuum environment of the generator jointly promote the heat and mass transfer process in the generator and improve the performance of the chiller.Particularly,experiment of heat pump combined with CPC-PV/T and small LiBr absoption chiller was conducted.First,main components and working principle of the system was described,and cooling water outlet temperature,electrical efficiency,thermal efficiency and other parameters of CPC-PV/T were obtained.After analyzing the feasibility of the overall scheme,the experiment of combined heat pump was carried out.The results show that the average hot water outlet temperature at the low temperature side of the heat pump is 35.1 °C,which is lower than the measured inlet temperature of the cooling water of the solar panel(36.5 ?),when using the cooling water produced by the PV/T collector as the heat source of the heat pump.The circulation of cooling water of CPC-PV/T is closed.The temperature of hot water on the high temperature side of the heat pump reaches 90 ?,which can meet the requirements of the temperature of the heat source of the chiller. |
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