Refrigerant evaluation and performance comparison for a novel hybrid solar-assisted ejection-compression refrigeration cycle

Abstract

This paper presents an investigation on refrigerant evaluation and performance comparison of a novel solar-powered hybrid ejection-compression cycle for space cooling or refrigeration. By reducing heat consumption and solar collector area, the novel ejection-compression cycle can have better practicality and performance than conventional hybrid ejection-compression cycle. A model for the novel hybrid cycle is proposed including a validated 1-D ejector model. Five refrigerants are selected from a series of candidate refrigerants and are further evaluated based on cycle performance. Finally, R152a is recommended for its good characteristics and performance. With R152a, the novel cycle is compared with conventional cycle. The results show that the novel cycle has both higher electric efficiency (COPele) and thermal efficiency (COPth), when rationally low solar heat is provided. At low heat region and Tg = 90 °C, the novel cycle only consumes 66.6 kW heat to increase COPele from 3.01 to 3.76, while the traditional cycle consumes 3 times the solar heat to achieve the same COPele. When more heat is consumed, the COPele of conventional cycle increases. However, the increasing installation space and capital cost of increasing collector greatly reduce the practicality of conventional cycle. Therefore, the novel cycle has better feasibility and good energy performance.