Abstract:
To solve the problem of ambient temperature increasing due to the direct discharge of condensation waste heat from air conditioners, the organic Rankine cycle was adopted to recover the condensation heat of the vapor compression refrigeration cycle. A combined cooling and power system with vapor compression refrigeration cycle and organic Rankine cycle was constructed. R134 a and R245 fa/R123(0.5/0.5) were used for vapor compression refrigeration cycle and organic Rankine cycle, respectively. Based on the first law of thermodynamics, the thermodynamic model of cycle was constructed, and the effects of evaporation temperature and condensation temperature on the performance of the combined cooling and power system under the conditions of absorbing total condensation heat and superheated part condensation heat were investigated and compared. The results show that with the increasing of condensation temperature of the vapor compression refrigeration cycle, the net power output of the organic Rankine cycle is increased from 5.7 kW to 6.4 kW, and the power generation is increased from 4.9 kW to 5.5 kW. The net power output is increased from 3.2 kW to 8.4 kW, and the net power generation is increased from 2.5 kW to 7.5 kW with the increasing of evaporation temperature of organic Rankine cycle. However, they are decreased with the increasing of evaporation temperature of vapor compression refrigeration cycle and condensation temperature of organic Rankine cycle. The COP(coefficient of performance) of the VCC-ORC with absorbing all condensation heat is increased by 17.9% to 26.9%. When the working fluid of organic Rankine cycle system absorbs the total condensation heat released by the steam compression refrigeration cycle system, the performance of working and electricity generation is obviously better than that of the recovery method with only absorbing the superheated part heat.