以太阳能为热源,建立超临界有机朗肯循环系统模型,选取7种有机工质作为研究对象,研究膨胀机进气温度和压力对系统的单位净输出功、不可逆损失和热效率等参数的影响,并用模糊数学模型筛选出最佳的工质.结果表明:工质R152a的综合性能更好,合适的进气温度和压力区域能够使系统保持在较高的热效率中运行,超临界有机朗肯循环系统相比于亚临界系统更具有优势.“,”Thermodynamic model of supercritical organic Rankine cycle is established by using solar energy as heat source.The impacts of crucial indicators for system,such as net power output,irreversibility and thermal efficiency are discussed in detail for seven organic working fluids.The best organic is screened by fuzzy mathematical calculation model.The result showed that R152a is a potential option for the supercritical Rankine cycle.Furthermore,the system can reach an optimum thermal efficiency by choosing a suitable turbine inlet temperature zone and a pressure zone.organic fluids provide higher efficiency in supercritical Rankine cycle compared to a subcritical Rankine cycle.