基于有限元法的黑体腔高温传感器动态特性分析

摘要

Based on finite element analysis method,three dimensional(3D)finite element model for blackbody cavity is established,analyze effect of structural parameters of blackbody cavity,thermal physical property parameters,initial preheating temperature on dynamic characteristics of blackbody cavity temperature measuring process. The result shows that change of blackbody cavity structure parameters directly influence on cavity dynamic temperature measurement error, dynamic response time,cavity emissivity,and then affects performance of blackbody cavity. The cavity dynamic measurement error increases with the increasing of heat capacity or density. Influence of blackbody cavity initial preheating temperature on dynamic temperature measuring of blackbody cavity is great,when the preheating temperature increases 100℃,the maximum dynamic measurement error reduces 50℃,dynamic response time reduces about 5 s.%基于有限元热分析法，建立了黑体腔三维有限元模型，分析了黑体腔结构参数、热物性参数、黑体腔初始预热温度对黑体腔测温过程中动态特性的影响。研究结果表明：黑体腔结构参数的改变直接影响黑体腔动态测温误差、动态响应时间、腔体发射率，进而影响黑体腔性能。黑体腔动态测温误差随着比热或密度的增大而增大。黑体腔初始预热温度对黑体腔动态测温影响较大，初始预热温度每增加100℃，最大测温误差减小50℃左右，动态响应时间减少5 s左右。