Performance of a beta Stirling refrigerator with tubular evaporator and condenser having inserted twisted tapes and driven by a solar energy heat engine

This paper investigates the performance of a beta-type Stirling refrigerator. The proposed refrigerator has twin tubular evaporator and condenser. The tubes of both evaporator and condenser have insertions of multiple twisted metallic tapes inside them. In the proposed refrigerator, a wire net regenerator is suggested. The working fluid is selected to be Helium. Rhombic drive mechanism controls the synchronization of the reciprocation of both the displacer and the piston. A computer program in the form of a spreadsheet is prepared to solve the refrigerator cycle numerically. The results get the more suitable dimensions of the evaporator, the condenser, the regenerator, and the more suitable stroke to bore ratio of both piston and displacer. The refrigerator develops 0.000283 TR/cc, COP = 0.5297 at 800 rpm. The comparison among the present work and previous ones shows that; the present refrigerator explores an enhancement in COP up to 100%, especially at low-speed levels. (C) 2018 Published by Elsevier Ltd.