PERFORMANCE ANALYSIS OF PARALLEL FLOW SINGLE AND DOUBLE EFFECT ABSORPTION CYCLES
Thermodynamic analysis of parallel flow single and double effect LiBr-H2O absorption system has been carried out. In the single effect cycle, the refrigerant leaving the evaporator is divided to flow in parallel and get absorbed partly in a heat recovery absorber and the remaining in a heat rejecting absorber. This reduces heat load of the generator to a great extent and hence, improves COP of the cycle. Similarly in the double effect parallel flow cycle, the solution leaving the absorber is divided into two parts, one being sent to the main generator and the other to the secondary generator. Such type of arrangement in the double effect system increases COP of the cycle as compared to the series flow cycle. The refrigerant distribution ratio (RDR) in the single effect refrigerant-parallel flow cycle and the solution distribution ratio (SDR) in the double effect solution-parallel flow cycle have been optimized. The optimization results, corresponding to the maximum COP, yield: RDR=0.30 and SDR=0.45. A comparative study between the single effect simple cycle, single effect cycle using heat recovery absorber, double effect parallel flow cycle and double effect series flow cycle has been presented. The analysis has been done by varying evaporator temperature (Te) from 5oC to 12.5oC and condenser/absorber temperature (Tc) from 30oC to 40oC.