基于L-M算法的管内流体流量及温度单参数识别

Study of Single Parameter Identification of Flow Rate and Temperature in Pipeline Based on L-M Algorithm

管道内部流量及温度的测量在工业生产和工程应用中具有重要作用。采用高温管道一维稳态导热模型探讨了管道外壁面温度随流体流量及温度的变化规律。基于管道外壁面温度,采用列文伯格-马夸尔特(Levenberg--Marquardt,L--M)算法对管道内流体流量及温度单参数识别进行了研究,并分析了外壁面上的测温点个数对识别结果的影响。结果表明,流体流量或温度与测温点温度之间是一一对应的;流体流量越小,流体温度越高,则流体流量的识别精度越高;流体流量越大,流体温度越高,则流体温度的识别精度越高;无论存在测温误差与否,流体流量及温度的单参数识别结果均非常精确。

The measurement of fluid flow rate and temperature inside pipelines plays an important role in industrial production and engineering applications.A one-dimensional steady-state heat transfer model for high temperature pipelines is used to investigate the variation of temperature of the outer wall of a pipeline with different fluid flow rate and temperature.On the basis of the temperature of the outer wall of a pipeline,a L-M algorithm is used to study the single parameter identification of fluid flow rate and temperature in the pipeline.The influence of temperature measurement point number on the identification result is analyzed.The results show that the fluid flow rate or temperature corresponds to the temperature of the related measurement point.The smaller the fluid flow rate is,the larger the fluid temperature is,and the higher the fluid flow rate identification accuracy is.The larger the fluid flow rate is,the larger the fluid temperature is,and the higher the fluid temperature identification accuracy is.The single parameter identification results of fluid flow rate and temperature are very accurate regardless of the existence of temperature measurement errors.