喷射器在跨临界CO₂热泵中的优化研究

Optimization of Ejector in Transcritical CO₂ Heat Pump

摘要: CO₂跨临界循环系统的研究一直是各界学者积极关注的热点，在目前的研究中采用喷射器代替节流阀植入到系统中是个不错的选择，一方面可以大量减少节流损失，另一方面可以提升压缩机的吸气压力，减少压缩机的耗功，从而可以起到提升热泵系统性能的作用。喷射器作为整个系统的核心部件它的工作性能对系统性能起着至关重要的作用。本文运用气体动力学函数法的基本理论，对喷射器的性能指标以及结构尺寸进行了分析和设计，并采用Fluent软件对CO₂工质在喷射器的内部流场和温度场变化展开了求解，将喷嘴效率、吸收室效率、与扩压室效率的计算取值与结构尺寸和工况参数进行了关联性研究，以表征各部件产生的流动不可逆损失。从而确定系统性能优化的方向。

Abstract: Study of CO₂ across critical circulation system is the attention of the scholars from all walks of life to actively, in the current study uses the injector to replace the throttle valve into the system is a good choice, on the one hand can substantially reduce the throttling loss, on the other hand can improve compressor suction pressure, reduce the power consumption of the compressor, which can improve the performance of heat pump system. As the core component of the whole system, the performance of the ejector plays an important role in the performance of the system. In this paper, by using the basic theory of gas dynamics function method, the performance of the injector and to analyze the structure size and design, and uses the Fluent software for CO₂ laser in the interior of the ejector to solve the flow field and temperature field, the efficiency of nozzle efficiency, absorption chamber, and the calculated values and structure size of the expansion pressure chamber efficiency and operating conditions for the correlation research, to represent the flow of the parts produced irreversible loss so as to determine the direction of system performance optimization.