Thermodynamic analysis including energetic and exergetic analysis is carried out employing Engineering Equation Solver for the five modified cycles: dual expansion cycle, internal heat exchanger cycle, work recovery cycle, work recovery with internal heat exchanger cycle and vortex tube expansion cycle. Contours are developed to study the effect of gas cooler temperatures and evaporator temperatures on the system performance and optimum gas cooler pressure. The modified cycle with work recovery turbine offers relatively higher COP and higher exergetic efficiency with lower compressor discharge pressure. The exergy loss in compressor, gas cooler, throttle valve and vortex tube (VT) are considerably higher than that in internal heat exchanger (IHX), evaporator and turbine. It is observed that COP of modified cycle with VT is slightly less than that with IHX, whereas the cycle with work recovery turbine brings the highest COP with the improvement of 25% at the gas cooler exit temperature of 305 K and evaporator temperature of 248 K.

中文翻译：

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改进的CO ₂跨临界制冷循环的能量和能量研究

使用工程方程求解器对五个改进的循环进行热力学分析，包括高能和高能分析：双膨胀循环，内部换热器循环，功回收循环，带有内部换热器循环的工作回收和涡流管膨胀循环。开发轮廓用于研究气体冷却器温度和蒸发器温度对系统性能和最佳气体冷却器压力的影响。带有工作回收涡轮机的改进循环可在较低的压缩机排气压力下提供相对较高的COP和较高的效率。压缩机，气体冷却器，节气门和涡流管（VT）的火用损失比内部热交换器（IHX），蒸发器和涡轮的火用损失高得多。