Improvement Of The Performance Of A Diffusion Absorption Refrigeration System Using Mixed Refrigerants

The reutilization of low grade energy attracts more attentions nowadays. The absorption refrigerator is a promising devoice to reutilize the low grade energy. The solution pump in the absorption system also consumes valuable electricity, while the diffusion absorption refrigerator (DAR) can only be driven by the low grade thermal energy instead of electricity to produce cooling. The conventional DAR uses ammonia/water/hydrogen as the working substance, which is unable to reach low-temperature due to the confine of the thermodynamic properties of the the working substance. Based on the review of DAR system at home and abroad, this paper investigated the DAR operating with the ternary mixture R23/R32/R134a or binary mixture R23/R227e as refrigerant, DMF as absorbent. He as inert gas. Main contents of the research are as follows:1. A review of the development of the DAR cycle and research status of the working substances of the DAR.2. Parameters of the state points in the DAR cycle were calculated using the self-developed programs based on VB software. The performances of the systems operating with R23/R32/R134a and R23/R227e were analyzed in detail. This work can be a reference for the optimization of the working substance in the DAR system.3. The experimental apparatus was improved three times, on the basis of that existed. The performance debugging of the system guaranteed the stable operation of the experimental system Preliminary experiment was conducted and experimental results were obtained for the R134a, R23/R134a and R23/R32/R134a systems, which lays a sound basis for the experimental optimization of the performance of the diffusion absorption refrigerator..