Energy analysis of a coupled power—refrigeration cycle

Abstract

This article presents the energy analysis of a coupled power—refrigeration cycle which eliminates the requirement of electrical power for driving the compressor of the vapour compression refrigeration cycle. The coupled cycle which uses pentafluropropane R-245ca as the working fluid in top power loop and bottom refrigeration loop have been assessed with different combinations such as cycle with recuperator, reheater, and economizer with a view to augment its performance. In the condenser temperature range of 30–42 °C and recuperator effectiveness range of 0.7–0.9, the overall coefficient of performance (COP) of the coupled cycle with the introduction of the recuperator, increased by 19.5–50.7 per cent and in the cycle with recuperator, reheater and economizer, it increased by 41.6–59.3 per cent. Overall COP at a constant turbine inlet temperature remains almost invariant with boiler pressure in the condenser temperature range of 30–42 °C for a coupled power–refrigeration base cycle and cycle with recuperator, reheater, and economizer. Significant decrease in overall COP is observed for boiler pressure greater than 5 MPa at constant turbine inlet temperature and recuperator effectiveness for the coupled cycle with recuperator.