考虑流动压降的有机朗肯循环热力性能分析  

Thermal performance analysis of an organic Rankine cycle considering flow pressure drop

作　　者：张皓衍 王志奇[1] 皮文博 鞠澄源 ZHANG Hao-yan;WANG Zhi-qi;PI Wen-bo;JU Cheng-yuan

机构地区：[1]湘潭大学机械工程与力学学院,湖南湘潭411105

出　　处：《节能》2024年第2期55-58,共4页Energy Conservation

基　　金：湖南省自然科学基金面上项目(项目编号:2021JJ30677)。

摘　　要：针对有机朗肯循环(ORC)系统建立流动压降与系统性能的数学模型,在不同的蒸发压力、过热度、夹点温差下以R134a、R245fa、R123、R600a、R236ea、R141b作为系统循环工质,分别计算变工况运行下的流动压降,探究ORC系统热效率变化系数在流动压降作用下的变化特性。结果显示,蒸发器压降是ORC系统流动压降的首要来源;影响ORC系统流动压降的决定性运行参数是蒸发压力,其次为夹点温差及过热度;蒸发压力低于0.8 MPa会导致系统热力性能的降幅增大;除R134a外,夹点温差与过热度对其余工质流动压降的影响较小,对应的系统性能变化系数均小于10%;系统采用R141b和R123的流动压降最小,此时流动压降对热效率的影响最低。For the organic Rankine cycle(ORC)system,a mathematical model of flow pressure drop and system performance was established,and the change characteristics of the thermal efficiency change coefficient of the ORC system under different evaporation pressures,superheat and pinch point temperature differences were calculated with R134a,R245fa,R123,R600a,R236ea and R141b as the system cycle working fluids,and the variation characteristics of the thermal efficiency change coefficient of the ORC system under the action of flow pressure drop were explored.The results show that the evaporator pressure drop is the primary source of flow pressure drop in the ORC system.The decisive operating parameters affecting the flow pressure drop of the ORC system are the evaporation pressure,followed by the temperature difference and superheat at the pinch point.If the evaporation pressure is less than 0.8 MPa,the decrease in the thermal performance of the system will increase.Except for R134a,the influence of the temperature difference and superheat on the flow pressure drop of the other working fluids is small,and the corresponding system performance change coefficients are less than 10%.The system uses R141b and R123 to achieve the lowest flow pressure drop,where the flow pressure drop has the lowest impact on thermal efficiency.

关 键 词：有机朗肯循环 流动压降 工质筛选 

分 类 号：TK123[动力工程及工程热物理—工程热物理]