Abstract:

Ejector cycle and two-stage evaporation cycle are two different ways to improve coefficient of performance (COP) for vapor-compression refrigeration or heat pump systems. They decrease the irreversible losses in throttling and heat transfer process, respectively. To further improve COP, a novel compressor-ejector cycle with two-stage evaporation is proposed. In this cycle, an ejector is applied to lift the lower evaporating pressure by recovering the expansion work. A thermodynamic model is developed to analyze performance of the new cycle. Numerical results indicate that COP of the new cycle under basic operating conditions is 20.4%, 10.9%, 7.6% higher than basic refrigeration cycle, ejector cycle and two-stage evaporation cycle, respectively. The improvement of COP is applicable to different refrigerants.

摘要：

喷射循环和双级蒸发循环都能有效提高蒸气压缩制冷循环COP，因为它们分别降低了由等焓节流和温差传热造成的热力学损失。为了进一步提高循环能效，通过复合使用上述两项节能措施，提出了一种压缩机和喷射器耦合的双级蒸发喷射循环。通过建立新型循环的热力学模型，使用数值计算的方法验证了其显著的节能效果。在特定工况下，双级蒸发喷射循环制冷COP较简单循环、喷射循环和双级蒸发循环分别可提升20.4%、10.9%和7.4%，且该循环在使用多种不同制冷剂时均能获得能效提升效果。