A Study of A Solar-driven Diffusion-absorption Refrigerator with an Adiabatic Spray Absorber

摘要

In order to utilize solar energy to drive absorption refrigeration system to meet the requirements of reserving food and air conditioning in a family at the same time, a new type of diffusion-absorption refrigeration experiment set with an adiabatic spray absorber is designed and manufactured. The triple fluid of LiNO3/NH3/He is used as working fluid. Based on the prototype machine and the stable thermodynamic models, theoretical results shows that the system can operate at evaporating temperature of-20~C when the generating temperature was in the range of 86～100°C and the corresponding coefficient of performance (COP) varied in the range of 0.11～0.49. Experiments are carded out on the prototype machine in which an adiabatic spray absorber is used and several plate-type heat exchangers are respectively used as generator, condenser, solution heat exchanger, solution cooler and evaporator. A NI LabView data acquisition (DAQ) system is set to measure the operating parameters such as temperatures, pressure and volumetric flow rates. Primary experiments show that the system can operate stably and produce cooling when the driving hot water temperature is in the range of 81～85°C, and the lowest evaporator temperature can reach -11.3~C if the condensing temperature and absorbing temperature are below 27.5°C. But the COP is just about 0.055～0.067 which is much lower than theoretical value. It also indicated that the heat transfer performances of the solution heat exchanger and solution cooler greatly affect the temperature of spray absorber (i.e. the absorbing temperature) and condensing temperature, which deteriorates the performance of the new type DAR.