从理论上分析了雾滴粒径与初速度对水平运动的影响,得到了不同粒径与初速度时的雾滴在水平方向上能达到的极限距离,分析了雾滴在水平穿越火焰区时蒸发量与火焰厚度以及雾滴速度之间的关系.从理论上分析了水雾水平作用于火焰与垂直作用于火焰的区别,提出了当水雾抑制竖直壁面火蔓延时,其灭火机理以表面相灭火为主,采用较小的雾滴粒径并不能达到更好的灭火效果.在标准燃烧室内开展了全尺寸实验,对理论分析结果进行了验证.
Water droplet cannot reach the wall unless it has enough muzzle velocity when it reaches the front of flame plane because of flow resistance in fire zone. Motion of water droplet varying in droplet size and original velocitiy is discussed and extreme length of droplet is gained. Relationships between droplet size and time and distance when water droplet passes through flame zone are analyzed. Considering different droplet sizes and velocities, fire suppression mechanisms can be divided into surface and gaseous suppression. The different between vertical and horizontal water spray is analyzed theoretically. It is found that when water is sprayed horizontally to lining material, surface suppression plays the major part. Then full-scale fire tests were conducted in the ISO 9705 room, whose results validated the theorical analysis.