Cycle analysis of an air-cooled LiBr/H2O absorption heat pump of parallel-flow type

A gas-fired absorption heat pump with cooling capacity of 2 RT was analysed as an air-conditioner for domestic use during the summer. The absorption heat pump considered was an air-cooled, double-effect, LiBr/H₂O system of parallel-flow type. The performance of the absorption heat pump in the cooling mode of operation was investigated through cycle simulation to obtain the system characteristics depending on the inlet temperature of air to the absorber, the working solution concentrations, the solution distribution ratio of the mass of solution into the first generator to the total mass of solution from the absorber, and the LTDs (leaving temperature differences) of the heat-exchanging components. When the predicted results were compared with the measured data for similar design conditions, reasonable agreement was observed. The optimum design and operating conditions of an air-cooled absorption system are suggested based on this cycle simulation analysis.