多波段水雾的遮蔽效应研究

Extinction Characteristics of Water Fog in Multiband

基于随机介质中波的辐射传输理论,采用蒙特卡罗数值模拟方法,研究了多波段水雾层的最佳遮蔽问题.数值模拟了满足对数正态分布水雾的质量消光系数随入射波波长、水雾粒径变化的关系,并与文献中单次散射数据进行了对比;计算了激光在水雾中透过率与波长、水雾宽度以及不同数密度的关系.结果表明,数密度比较大时,必须考虑多重散射;水雾的粒径选取与被遮蔽激光波长相近,就可以得到最佳遮蔽效果;而且用反射率或透过率能更方便的反映烟幕的消光性能,这对烟幕遮蔽性能的研究具有重要的理论参考价值。

Based on wave radiation transmission theory in random medium and Monte-Carlo method, the optimum extinction characteristics of water fog in multiband is studied. The effect of incident wavelength and particle radium on the mass extinction coefficients of the water fog with lognormal distribution is numerically simulated. And the numerical results is compared with the document data. The transmittance of the laser in the mist is calculated, which is related to wavelength, the width of water fog and the number density. The results show that the multiple scattering must be considered when the number density is thick. The best screening effect can be obtained when the particle radium chosed is closed to the wavelength of the extincted laser. And transmission or reflectivity makes evaluation of the fog more convenient. It has theoretical reference value to the research of the screening performance on smoking