Two-phase ejectors are used in the refrigeration cycles to decrease the throttling losses and improve the performance. The subject of this paper is the motive nozzle which is the critical component of the ejector since the pressure distribution throughout the motive nozzle affects the secondary fluid to be entrained into the ejector. A simplified version of the one of the previously established one-dimensional (1-D) converging-diverging motive nozzle models is developed in this paper to calculate the pressure, temperature, velocity, and Mach number distributions. 1-D model of the nozzle is established based on the conservation equations of mass, momentum, and energy and the equation of state under steady, frictional, and adiabatic flow assumptions with the homogeneous equilibrium condition. Maximum differences of the pressure drop throughout the nozzle between the literature data and the calculated results are around 6% and 8% for CO₂ and R134a nozzles, respectively. The main objective is investigating the effects of the subcooling temperature difference, inlet pressure (condenser temperature or pressure), mass flow rate, and motive nozzle outlet diameter for R134a, R1234yf, and R1234ze(E). Parametric comparisons and evaluations are used to lead the motive nozzle designs for the further numerical and experimental studies including these new generation refrigerants for R134a replacement.

在制冷循环中使用两相喷射器可减少节流损失并提高性能。本文的主题是动力喷嘴，它是喷射器的关键组件，因为整个动力喷嘴的压力分布会影响要夹带到喷射器中的二次流体。本文开发了一种先前建立的一维（1-D）收敛-发散动力喷嘴模型的简化版本，以计算压力，温度，速度和马赫数分布。基于质量，动量和能量守恒方程以及均质平衡条件下的稳态，摩擦和绝热流动假设下的状态方程，建立了喷嘴的一维模型。_2个喷嘴和R134a喷嘴。主要目的是研究R134a，R1234yf和R1234ze（E）的过冷温度差，入口压力（冷凝器温度或压力），质量流量和喷嘴出口直径的影响。使用参数比较和评估来引导喷嘴的设计，以进行进一步的数值和实验研究，包括用于替换R134a的这些新一代制冷剂。