Organic flash cycle (OFC) can effectively use low‐ and medium‐temperature heat sources. The non‐isothermal phase change characteristic of R600a/R601a mixtures can improve the thermal match between the cycle and heat sink. In this study, a thermodynamic model of the OFC system was proposed. The OFC system was driven by heat source temperatures of 100–200 °C. R600a/R601a mixtures were selected as the working fluids. The effects of the mole fraction of the mixtures and the heat source temperature on the net power output, cycle efficiency, and second‐law efficiency were investigated. The exergy destruction in the component was also discussed. Results showed that when the heat source temperature was 100–180 °C, the relative increments in the net power outputs of the mixture systems were 0.62–5% compared with that of the R601a system. At 190–200 °C, the R601a system demonstrated the largest net power output. A characteristic temperature (T_ct) was also observed. When T_HS,in ≤ T_ct, the net power output was mainly affected by the thermal match between the cycle and the heat sink, flashing process destruction, and low‐pressure throttle valve destruction. When T_HS,in > T_ct, the net power output was mainly affected by the thermal match between the cycle and the heat sources.

中文翻译：

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R600a / R601a混合物对有机闪蒸循环的热力学分析▴

有机闪蒸循环（OFC）可以有效地使用中低温热源。R600a / R601a混合物的非等温相变特性可以改善循环和散热片之间的热匹配。在这项研究中，提出了OFC系统的热力学模型。OFC系统是由100-200°C的热源温度驱动的。选择R600a / R601a混合物作为工作流体。研究了混合物的摩尔分数和热源温度对净功率输出，循环效率和二次律效率的影响。还讨论了组件中的火用破坏。结果表明，当热源温度为100–180°C时，与R601a系统相比，混合系统的净功率输出的相对增量为0.62–5％。在190–200°C下，R601a系统展示了最大的净功率输出。特征温度还观察到了T _ct）。当Ť _HS，在≤ Ť_克拉，净功率输出主要受周期和散热器，闪烁过程破坏，和低压节流阀破坏之间的热匹配。当T _HS，in > T _ct时，净功率输出主要受循环和热源之间的热匹配影响。