摘要
针对自复叠制冷系统运行过程中组分浓度难以实时连续测量的问题,提出了一种混合工质循环浓度在线测量方法,用于精确测量系统内组分循环浓度、热力学参数及系统能效。在线测量方法基于系统内部件的组分、质量和能量守恒关系,基于温度、压力、流量数据测量组分循环浓度。搭建自复叠制冷系统实验平台,在柜内温度-58.6~-40.4℃的实验工况下验证了在线测量方法的可行性,并与气相色谱单时静态采样方法对比验证组分在线测量方法的准确性。研究结果表明:温度是影响组分的关键参数,实验测试值与在线测量值偏差小于3 K,组分循环浓度的在线测量值与气相色谱采样测量值对比最大偏差为4.45%。不确定度计算结果显示,组分循环浓度的在线测量不确定度低于2.0%,能效比和制冷量的在线测量不确定度低于7.5%。所提在线测量方法能够准确预测自复叠制冷系统的组分循环浓度,与气相色谱单时静态采样相比,可获取组分浓度的动态连续变化趋势,为从组分层面深入分析混合工质热力系统的性能变化提供依据。
In response to the challenge of real-time continuous measurement of component concentrations during the operation of auto-cascade refrigeration systems,an online measurement method for the circulating concentration of mixed refrigerant is proposed to accurately measure the circulating component concentrations,thermodynamic parameters,and system efficiency.The online measurement method is based on the composition,mass and energy conservation of components within the system.The circulating concentration of compositions is measured based on temperature,pressure and mass flow rate.An experimental platform for the auto-cascade refrigeration system is established to validate the feasibility of the online measurement method under experimental conditions with cabinet temperatures ranging from-58.6℃to-40.4℃.The accuracy of the online measurement of the composition is further verified using gas chromatography single-time static sampling methods.The research findings indicate that temperature,a crucial parameter affecting the composition,shows a deviation of less than 3 K between the experimental and online measurement values.The maximum deviation between the online measurement values of the composition concentration and the sampling measurement values is 4.45%.The uncertainty calculations show that the online measurement uncertainty of composition circulating concentration is below 2.0%,while the online measurement uncertainty of energy efficiency ratio and refrigeration capacity is below 7.5%.The proposed online measurement method can accurately predict the circulating concentration of the mixed refrigerant in auto-cascade refrigeration systems.In comparison with gas chromatography single-time static sampling,it allows for dynamic continuous trends in component concentrations,providing a basis for in-depth analysis of performance changes in mixed refrigerant thermodynamic systems at the component level.
作者
李银龙
景栋梁
刘国强
晏刚
LI Yinlong;JING Dongliang;LIU Guoqiang;YAN Gang(School of Energy and Power Engineering,Xi’an Jiaotong University,Xi’an 710049,China)
出处
《西安交通大学学报》
北大核心
2025年第4期139-147,共9页
Journal of Xi'an Jiaotong University
基金
国家自然科学基金资助项目(52076160)。
关键词
自复叠制冷系统
在线测量方法
混合工质
循环浓度
auto-cascade refrigeration system
online measurement method
mixed refrigerant
circulating concentration
作者简介
李银龙(1996—),男,博士生;通信作者:刘国强,男,助理教授。
