Study Of A Heat And Cold Storage Solar Ejection-Compression Hybrid Refrigeration System

Energy shortage and environment pollution are serious threat to human survival and development.The continuous improvement and optimization of ejector refrigeration technology has important practical significance to low energy consumption,make full use of primary energy and environmental protection.In this paper,the performance of the heat and cold storage solar ejection-compression hybrid refrigeration system and the building integration is studied.The feasibility and practicability of the system in Taiyuan is analysied.Ejector structure design and performance calculation program are compiled by FORTRAN language which is based on one-dimensional constant pressure uniform mixture model and the theory of gas dynamics.Using R141b as refrigerant,the calculation results show that,under a a certain evaporation temperature,the entrainment ratio decreases with the increase of condensing temperature.Under the same condensation temperature,the entrainment ratio first increases then decreases with the increase of occurring temperature and decreases with the increase of condensing temperature.Corresponding to different evaporation temperature,the maximum entrainment ratio has the best occurring temperature to match,and the best occurring temperature decreased with the increase of evaporation temperature.The maximum entrainment ratio also increases with the rise of evaporating temperature and decressed with the increase of condensing temperature.And under the same evaporation and condensation temperature,the ejector of biggest throat area ratio has the largest maximum entrainment ratio.The solar collector uses flat collector.Thermal storage device adopts stratified heat storage tank.Based on TRNSYS software simulation of solar heating system,the performance of solar ejector refrigeration system in typical weather day(July 11)is studied.Results show that,the tendency of the entrainment ratio,refrigerating capacity and COPh is consistent in typical weather day(July 11)to three different throat area ratio ejectors as r = 6.6,r ＝7.5 and r ＝ 8.8.In the certain condensation temperature,the performance of the system increases with the evaporating temperature.The ejector refrigeration system with the largest throat area ratio has the best performance,however running time is the shortest.Using TRNSYS software simulates some small office building of area of 286.14 in Taiyuan.The results show that,the temperature of the air conditioning room fluctuates up and down at 26℃ due to the influence of various factors such as solar radiation intensity,environmental temperature and so on.Building summer maximum cooling load is 22.31 kW,which can provide the calculation basis for the design of using the heat and cold storage solar ejection-compression hybrid refrigeration system in summer.This paper designs the heat and cold storage solar ejection-compression hybrid refrigeration system based on the building maximum cooling load in summer and the solar heating part is simulated by TRNSYS.From the system of cooling capacity,power consumption comprehensive performance coefficient and so on analyzes the performance of the system in air conditioning season.The results show that,using cooperatively of the ejector refrigeration,compression refrigeration and cold storage system can completely meet the demand of hourly cooling load of users in air conditioning season.The ejector refrigeration system can provide users with more than 50%of the amount of cooling.The heat and cold storage solar ejection-compression hybrid refrigeration system can save more than 40%of the electricity compared with pure compression refrigeration system.The system integrated thermal performance coefficient can rearch to 0.36,the comprehensive mechanical performance coefficient is 18.97.Taiyuan area can promote the use of the system,but need to be further optimized.