高温宽粒径氧化铝颗粒辐射特性研究

Study on radiative properties of high temperature and wide size alumina particles

基于Mie散射理论研究了温度分布为400~1000℃,粒径分布为0.1~20.0 mm的单个氧化铝颗粒的辐射特性参数。研究发现,当温度处于400~1000℃时,直径为3.0 mm的氧化铝颗粒已基本满足大粒子辐射特性,而0.1~3.0 mm的氧化铝颗粒衰减效率因子、散射效率因子、吸收效率因子随粒径的增加而急剧衰减,散射反照率随粒径的增加而急剧增加。基于最小二乘法对温度分布为400~1000℃,粒径分布为0.1~3.0 mm的氧化铝颗粒辐射特性效率因子进行拟合,拟合优度达到0.999以上,表明可以利用此非线性回归方程对此温阈、粒阈氧化铝颗粒辐射特性效率因子进行较精确的计算。

Based on the Mie theory,the investigation of radiative properties of a single alumina particle with a temperature distribution of 400-1000℃ and a particle size distribution of 0.1-20.0 mm are conducted.The results show that the alumina particles with diameter of 3.0 mm can basically represent the radiative characteristics of large particles.The extinction efficiency factor,scattering efficiency factor and absorption efficiency factor of alumina particles with diameter less than 3.0 mm sharply decay with the increase of the particle size,while the scattering albedo is the opposite.Further,based on the least squares method,the radiative characteristics efficiency factor o£alumina particles with a temperature distribution of 400-1000℃ and a particle size distribution of 0.1-3.0 mm arefitted.The goodness of the fit of these fitting curves can reach up to 0.999,indicating that these curves can be used for accurately calculating the alumina particle radiation characteristics in this temperature threshold and grain threshold.