Optimizing Analyses On Performances Of An Absorption Refrigeration System Operating With Mixed Refrigerants

With the increasingly serious problems of the energy shortage and environment pollution,reducing the energy consumption and improving the energy comprehensive utilization rate are the fundamental way to solve the energy problem. Absorption refrigeration systems can bedrven by the low grade thermal energy, such as waste heat, solar thermal heatetc. But traditional absorption refrigeration systems are is limited by their working fluids and the cycle configurations, which are not suitable for deep freezing applications.More and more attentions have been attracted into the absorption refrigeraton systems because they can be used in the deep freezing applications where a lot of waste heat can be utilized. Based on the review of absorption refrigeraton systems at home and abroad, this paper carried on the theoretical analyses on both Linde-Hampson absorption refrigeraton system and Auto-Cascade absorption refrigeraton system. An experiment setup was also built up to conduct experimental investigations. Main contents and consequences of the research were as follows:(1) Optimizing analyses on performances of the Linde-Hampson and Auto-Cascade absorption refrigeraton systems operating with R23/R134a/DMF and R23/R227ea/DMF were conducted. The optimal cycle pressures and optimal concentrations of the working fluidss were obtained as well as the optimization method.(2) An experiment setup was also built up to conduct experimental investigations for Linde-Hampson and Auto-Cascade absorption refrigeraton systems. The influences of the expansion valves, flowrate of the solution pump, component of the refrigerant mixture, liquid level of the generator and absorbor on the system performance were investigated.(3) The experimental results showed that the main refrigerant valveopening, condensing temperature and generation temperature have great influences on the high pressure, but the bottom valve opening, evaporation temperature, absorption temperature have great influences on the low pressure.(4) In experiment, a lower refrigerating temperature was obtained in the Auto-Cascade absorption refrigeraton system comparing with Linde-Hampson absorption refrigeraton system under the same working condition, which confirmed the results of the theoretical analysis at some extent.