Thermodynamic Analysis of Vapour Compression- Absorption Two Stage Refrigeration Cycle

Abstract

At low temperature applications and large cooling capacities, ammonium refrigerant used widely and these type refrigeration applications have electrical energy consuming by using vapour compression cycle. This causes increasing cooling cost, consuming more fossil fuel and to create environment problem. The vapour compression-absorption two stage refrigeration cycle is alternative to solve this overcoming problems. In this study, a thermodynamic analysis of the vapour compression-absorption two stage refrigeration (novel cycle) was performed. While NH 3 -H 2 O was used as fluid pair in the absorption section, NH 3 was used in the vapour compression section. It was presented that electrical energy consumption in the novel cycle is 60% lower than classical one stage vapour compression refrigeration cycle and 24% lower than single effect vapour compression-absorption cascade refrigeration cycle. The thermodynamics analysis was performed for different condenser and generator temperatures. The result shows that COP of the novel cycle increases by increasing the generator temperature, while it decreases by increasing the condenser temperatures. The exergetic efficiency of the system decreases on increasing the generator and condenser temperatures. The novel cycle provide by using inexpensive alternative heat energy sources like solar energy, geothermal energy and waste heat at low temperatures.