热电偶导热在壁面温度测量中所引起的误差—着重高热负荷壁面的温度测量

Analysis of Thermocouple Conduction Errors in the Measurement of Surface Temperature—With Particular Emphasis on the Measurement of Surface Temperature for Walls Carrying High Heat Flux

从问题的数学描写出发,文章对现有解进行了仔细的评述,指出了它们的近似性质和适用范围。对于高热负荷壁面的测温误差问题,文章在比现有解更加符合实际的边界条件下,获得了问题的解析解。这个解析解可以表成下列准则方程式,(?)式中,(?),是热电偶接点处的无量纲偏差温度,(?),是个变相的比奥准则,(?),是个比奥准则。文章还进一步对减小测温误差偏离计算结果的热电偶安装方案,解析解对有限厚度壁面的适用性等进行了讨论。

Starting from the proper mathematical formulation of the physical problemthe present paper reviews critically all available solutions.The nature ofapproximation and the range of applicability of these solutions are discussed,For the problem of conduction errors for walls carrying high heat flux,thispaper presents an analytical solution with boundary conditions approximatingreal situations.The solution may be put in the following dimensionless form:(?)where Θ is a dimensionless temperature difference at the junction of thethermocouple and the wall surface,(?)is a modified Biot modulus,B_2=(αD)/λ is a Biot modulus.Graphs and tables are provided for the convenienceof technical calculations.Among the topics further discussed in the paper arethermocouple installation scheme for minimizing deviations with reference tothe calculated errors and the applicability of the solution to walls of finitethickness.