Xin Cheng-Yun, Cheng Xiao-Fang, Zhang Zhong-Zheng
Department of Thermal Science and Energy Engineering, University of Science and Technology of China, Hefei 230027, China.
Guang Pu Xue Yu Guang Pu Fen Xi. 2013 Feb;33(2):316-9.
Based on Planck's law, the surface temperature of an object can be determined by measurement of emitted radiation. The equation for monochromatic radiation thermometry within a finite solid-angle was deduced, and it was found that if the surface temperature and spectral emissivity can be solved at the same time, the specific radiation measurement conditions for multi-spectral thermometry should be generally met that the radiation measurement should be implemented within an infinitesimal solid-angle or within a finite solid-angle only for a perfect diffuser. When the directional spectral emissivity modeled by finite polynomial series is employed and proper mathematical transformation is used, a universal equation for monochromatic radiation thermometry is obtained. So the restrictions in radiation measurement can be got rid of, but spectral emissivity may not be solved simultaneously. Multi-solution problem was preliminarily investigated, and so a solution was put forward that the channel number should be more than the number of the variables to be solved and the nonlinear least squares method should be used.
基于普朗克定律，可通过测量物体发射的辐射来确定其表面温度。推导了有限立体角内单色辐射测温的方程，发现若能同时求解表面温度和光谱发射率，则多光谱测温的特定辐射测量条件通常应满足：辐射测量应在无限小立体角内进行，或仅对理想漫射体在有限立体角内进行。当采用有限多项式级数建模的定向光谱发射率并进行适当的数学变换时，可得到单色辐射测温的通用方程。这样就可以消除辐射测量中的限制，但可能无法同时求解光谱发射率。对多解问题进行了初步研究，进而提出一种解决方案，即通道数应多于待求解变量的数量，并应采用非线性最小二乘法。
