压缩机和喷射器耦合的双级蒸发喷射循环性能分析

Performance analysis of a novel compressor-ejector cycle with two-stage evaporation

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。

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.