| Previous experiment results show that the heating capacity decreases with the increment of water flow rate, if the water temperature at inlet of evaporator and condenser, and the water flow rate in evaporator are constant. In allusion to this special phenomenon, new experimental studies of cyclic characteristics of zeotropic mixtures are carried out.The refrigerant is zeotropic mixture (mass ratio: R22/R142b, 0.26/0.74). On the base of the improvements of the existing system and optimized experiment methods, previous experiments are repeated. The new results show that the condensation pressure and compressor power are lower, the heating capacity and COP are higher, compared to the previous experiment results. The same changing rule with previous experiment of cyclic parameters and performance indexes is obtained. The heating capacity still deceases with the increment of water flow rate. Experiments for different water flow rate in evaporator are carried out at five water temperature at inlet of evaporator. The results indicate that with the increment of water flow rate, the evaporation pressure does not change, superheat degree increases. Cooling capacity decreases with the increment of water flow rate.The temperature distribution profile of refrigerant and heat transfer fluid is drawn by using experiment data and theoretical model of heat exchanger. According to the profile, local and total heat transfer coefficient is calculated. Results show that the increment of water flow rate in condenser does not bring the increment of total heat transfer coefficient between working fluid and water, but evaporator does. The thermodynamics perfection is introduced to evaluate the effect on the system taken by the change of water flow rate from the view of second law of thermodynamics. The increment of water flow rate in condenser decreases the thermodynamics perfection, and in evaporator increases the thermodynamics perfection.
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