CAJ | 학술논문

为研究添加遮光剂对 SiO2气凝胶热辐射特性的影响，分别采用考虑基质吸收的改进的 Mie 散射理论和经典的Mie 散射理论计算了气凝胶基质中单个粒子的热辐射特性和遮光气凝胶总的热辐射特性，并将两种方法的计算结果与已有实验数据进行了对比。分析了遮光剂粒子尺寸、分布规律对遮光气凝胶热辐射特性的影响，计算了遮光气凝胶的辐射热导率和不同温度下的最优粒径。结果表明：气凝胶基质的吸收作用对基质内的粒子散射影响较小，在计算遮光气凝胶热辐射特性时可以忽略。采用 TiO2均一粒子系作为遮光剂，温度为300、500、700、900 K 时的最优粒子半径分别为1.4、1、0.75、0.6μm。
위연구첨가차광제대 SiO2기응효열복사특성적영향，분별채용고필기질흡수적개진적 Mie 산사이론화경전적Mie 산사이론계산료기응효기질중단개입자적열복사특성화차광기응효총적열복사특성，병장량충방법적계산결과여이유실험수거진행료대비。분석료차광제입자척촌、분포규률대차광기응효열복사특성적영향，계산료차광기응효적복사열도솔화불동온도하적최우립경。결과표명：기응효기질적흡수작용대기질내적입자산사영향교소，재계산차광기응효열복사특성시가이홀략。채용 TiO2균일입자계작위차광제，온도위300、500、700、900 K 시적최우입자반경분별위1.4、1、0.75、0.6μm。
To study the effects of adding opacifier to silica aerogel on its thermal radiation characteristics,the ther-mal radiative characteristics(TRC)of a single particle embedded in the aerogel matrix and the TRC of the opaci-fied aerogel were calculated by using the modified Mie scattering theory that takes the absorption of the matrix into account and the classical Mie scattering theory. The calculated results were compared with the experimental data in the literatures. The influence of the particle′s size and distribution of the opacifier on the TRC of the opacified aero-gel was analyzed. The radiative thermal conductivity(RTC)and the optimum particle size at different temperatures of the opacified aerogel were also computed. It was shown that the influence of the absorption of the aerogel matrix on the scattering of the particle embedded in the matrix is very small and can be neglected when calculating the TRC of the opacified aerogel. For the TiO2 opacified aerogel with a uniform TiO2 particle size distribution,the opti-mum particle radii are 1.4,1 ,0.75 ,0.6 μm at temperatures of 300,500,700,900 K,respectively.