Study On Performance Of Adsorption Refrigeration System Based On Hybrid Adsorbent

The rapid development of social economy make people’s standard of living has improved significantly. However, most buildings’ cooling way is still using the high quality energy and few recycle of the low quality energy, which caused a serious waste of energy. Therefore, the research and development of new type of cooling way is imminent. The research and development of new pollution-free refrigerants and new type refrigeration mode have become increasingly urgent. Owing its advantages like energy saving and environment protection and using a low quality energy for external heat source, absorption refrigerant has been the research focus of refrigerant industry. But extensive application and popularization of absorption refrigerant has been limited by its low COP.In the purpose of improving the COP of absorption refrigerant system, our team started from easing contradiction between heat and mass transfer of adsorbent. The previous study found that the hybrid adsorbent with the quality ratio of 10:7 mixed by active carbon and iron performance the best mass and heat transfer. To research the performance factors of this hybrid adsorbent in refrigerant system. This thesis referenced, classified and summarized the research status and progress of adsorption refrigerant system, and conduct theoretical analysis. on this basis, the mathematical model of the adsorption refrigeration system with basic cycle is established. When the parameters change, the adsorption refrigerant system performance changing law has been calculated by MATLAB. Meanwhile,heat and mass transfer adsorption refrigerant test bench was designed and built. This thesis researched adsorption refrigerant system performance changing law affected by desorption temperature Tg2 and contrast the experiment results and simulation results.Through the simulation of MATLAB, found that with the adsorption temperature Ta2=10℃, the evaporation temperature Te=4℃, the condensation temperature Tc=34℃ and the desorption temperature Tg2 increasing from 80 ℃ to 94 ℃, the adsorption refrigerant system cycle COP would increase. The experiment found that when the desorption temperature Tg2 maintain a constant the refrigeration cycle with mass and heat recovery COP reaches the maximum 0.236; however the basic adsorption refrigeration cycle COP reaches the minimum 0.087. The simulation results show that with the desorption temperature Tg2 increasing from 80℃ to 94℃, the adsorption refrigerant system cycle COP would increase from 0.324 to 0.371 in a speed slowing over time. Comparing the result of the experiment and simulation results shows that the theory of adsorption refrigeration system cycle COP is greater than the actual cycle COP.When the desorption temperature Tg2 maintain the constant, through the simulation of MATLAB, found that when with the adsorption temperature Ta2 increasing from 5℃ to 40℃, adsorption refrigerant system cycle COP would decrease from 0.378 to 0.151; with the evaporation temperature Te increasing from 2℃ to 10℃, the adsorption refrigerant system cycle COP would increase from 0.033 to 0.853; with the condensation temperature Tc increasing from 30℃ to 46℃, adsorption refrigerant system cycle COP would decrease from 0.456 to 0.07.Through the research of pressure, refrigerating capacity and SCP of the adsorption refrigeration system, found that before reaching the max desorption temperature of hybrid adsorbent, adsorption refrigerant system cycle would shrink with the increasing of desorption temperature; for adsorption refrigerant system with three cycle ways, as desorption temperature increasing from 82℃ to 94℃, the system cooling capacity is proportional to the desorption temperature Tg2 and cycle COP and SCP will increase with a speed lowing over time; for adsorption refrigerant system with three cycle ways, when desorption temperature Tg2 is constant, adsorption refrigerant system utilizing mass and heat recovery gets maximum system cooling capacity and SCP, respectively 1.460 k W and 50.339W/Kg. The basic adsorption refrigerant system gets minimum system cooling capacity and SCP, respectively 0.535 k W and 18.450W/Kg.