含雾湿空气条件下地面目标热特征分析方法

Characteristics analysis of ground targets in foggy weather

采用考虑自然雾对太阳辐射的衰减、散射作用进而修正的太阳辐射模型,且考虑含雾湿空气条件下雾滴、湿空气与目标表面的换热机理及表面辐射换热、对流换热,建立了含雾湿空气条件下地面目标热特征分析模型,采用该模型计算分析了雾能见度、风速对目标表面温度的影响,分析了典型雾天条件下目标表面温度变化特性。结果表明:在雾出现时段,雾能见度越小或风速越大,目标表面温度值相对越低;考虑雾对目标表面热特征的影响具有很大的必要性。

Based on the modified solar model by considering the attenuation and scattering of the fog, and considering the heat transfer mechanism between fog droplets and target surface in the foggy weather and the radiation and convection heat transfer of the surface, the heat transfer model of the ground target surface in the foggy weather was founded. The influence of fog visibility and wind speed on the target temperature field was analyzed by the heat transfer model. The temperature time variation characteristics of the targets in the typical foggy weather was also analyzed. The result shows that during the appearance of the fog, the smaller the fog visibility, the lower the temperature of the target surface; the higher the wind speed, the lower the temperature of the target surface. So it′s very necessary to consider the influence of the fog and wet air during the heat calculation of the ground targets.