临界温度对有机朗肯循环工质性能影响研究

The Impact of Critical Temperature on the Performance of Organic Rankine Cycle Working Fluids

摘要: 为探究工质临界温度对ORC系统工质性能的影响，选取R245fa、R236fa、RC318、R152a、R134a、R143a、R141b、R142b和R600a九种循环工质，利用Aspen Plus建立ORC系统模型，研究不同蒸发压力下工质临界温度对系统性能的影响。分析结果表明工质流量随蒸发压力的增大而减小，干工质的流量受蒸发压力的影响最大；膨胀机输出功率随蒸发压力的增大而增大，且随着蒸发压力升高，膨胀机输出功率的增大趋势逐渐减缓；在同一蒸发压力下，系统热效率和㶲效率与工质的临界温度均呈正相关关系。

Abstract: In order to investigate the influence of working fluid critical temperature on the performance of Organic Rankine Cycle (ORC) systems, nine working fluids including R245fa, R236fa, RC318, R152a, R134a, R143a, R141b, R142b, and R600a were selected. An ORC system model was established using Aspen Plus to study the impact of working fluid critical temperature on system performance under different evaporating pressures. The analysis results indicate that the working fluid flow rate decreases with increasing evaporating pressure, and the flow rate of dry working fluid is most affected by evaporating pressure. The output power of the expander increases with increasing evaporating pressure, and the increasing trend of expander output power gradually slows down as the evaporating pressure rises. Under the same evaporation pressure, the thermal efficiency and exergy efficiency of the system are positively correlated with the critical temperature of the working fluid.