Theoretical analysis of a new hybrid system with two ejectors.

Theoretical analysis of a new energy system. The proposed cycle combines the Rankine cycle and the ejector refrigeration cycle by adding a turbine between the boiler and the two ejectors. The combined cycle can produce both power and refrigeration at two different pressure and temperature levels with only one heat source. A simulation was carried out to evaluate the cycle performance using R123 as a working fluid. A one-dimensional mathematical model of the ejector was developed using the equations governing the flow and thermodynamics based on the constant-area ejector flow model. The ejector is studied in optimal operating regime. The model includes effects of friction at the constant area mixing chamber. The programming language is FORTRAN and thermophysical properties of refrigerants are evaluated using the base REFPROP V 9.1.The influence of thermodynamic parameters on the system performances is studied. The results show that the condenser temperature, the evaporation temperatures, the extraction ratio, the turbine inlet pressure and temperature has a significant effect on the system performances.

新型能源系统的理论分析。所提出的循环将朗肯循环（Rankine cycle）与喷射制冷循环（ejector refrigeration cycle）相结合，在锅炉与两个喷射器之间增设了涡轮机。该复合循环仅需单一热源，即可在两种不同的压力与温度工况下同时产出电能与冷量。为评估该循环的性能表现，研究以R123作为工质开展了仿真研究。基于等截面喷射器流动模型，结合流动与热力学控制方程，建立了喷射器的一维数学模型，并针对其最优运行工况展开研究。该模型纳入了等截面混合室内的摩擦效应。本研究采用FORTRAN语言完成编程，制冷剂的热物理性质通过REFPROP V9.1基准版本进行计算。研究分析了热力学参数对系统性能的影响规律。结果表明，冷凝器温度、蒸发温度、抽汽率、涡轮机进口压力与进口温度均对系统性能具有显著影响。