An improved absorption refrigeration cycle driven by unsteady thermal sources below 100 degrees C

This paper deals with an improved absorption refrigeration cycle with stage d absorption. Instead of having only one absorber, the improved cycle uses a series of absorbers among which one is cooled by the external medium and the others are cooled by refrigerant at staged pressures between the evapor ation pressure and condensation pressure. Ammonia-lithium nitrates (NH3-LiN O3) are selected as the working fluids and the calculation results for the two-staged cycle and the three-staged cycle are analysed in detail. It is d emonstrated that the improved cycle is able to steadily run when driven by low-grade thermal sources as low as 65 degrees C, and to produce deep refri geration temperature as low as -40 degrees C. Copyright (C) 2000 John Wiley & Sons, Ltd.