自动消防水炮的喷水强度分布特性及其控火性能研究

Water Density Distribution and Fire Control Capability of Auto-Regulative Water Gun

喷水强度是决定自动喷水灭火系统性能的重要参数。自动消防水炮在火灾早期可以快速响应,探测火源位置并自动喷水扑灭火灾。但如果由于某些因素不能及时响应,控制火灾的发展就是该系统的主要目标。传统的自动消防水炮研究只考虑射程和流量,没有考虑喷水的强度分布特性。本文将喷水强度引入自动消防水炮的控火性能研究,通过实验研究其在不同射程处的喷水强度分布特性,并参照不同危险等级的场所控制火灾所需的喷水强度参数来推算其有效保护区域和可控制的最大火源功率。研究结果表明:自动消防水炮在有效射程内,不同射程点的喷水强度、有效保护面积有所不同,喷水强度分布具有不均匀性。自动消防水炮应在火灾发展到最大有效保护面积之前自动或手动启动,才能达到有效控制火灾的目的。对于本文研究的某特定类型水炮,在20m至40m的射程范围内,应用于不同火灾危险等级场所,最大有效保护区域面积和可控制的最大火源功率均随射程增加而增加;而在40m至50m的射程范围内,应用于轻危险等级场所,最大有效保护区域面积随射程增加而增加,而其它危险等级场所的最大有效保护区域面积随射程增加而降低。

Water density is the determinate parameter for fire control. Auto-regulative Water Gun （AWG） can be used to detect a fire at early stage and inject water directly to fire source. However, if AWG cannot quickly response as designed due to man agernent or system failure, fire control will be the main manually operation purpose, like the sprinkler system. . Conventional research on AWG system is focused on injection distance and flow rate, without distribution characteristics of water density considered. In present paper, water density was used to study the fire control capability of AWG. The water density distribu tior was measured with water containers placed at various locations along the AWG injection direction, and the effective fire protection area and maximum fire to be controlled were deduced by referred to the required critical water density for various class fire control using sprinkler. For a design growing fire, e.g. a t square fire, the required latest activation time for AWG system can be determined. The fire can be controlled before reaching the effective protection area. Results indicate that water density and effective protection area vary with injection distance. The water coverage shape are different between axial and radius directions. Water density distribution is non-uniform and decreases with the injection dis tanee. For this study, the maximum effective protection area increases with injection distance from 20 to 40m. While from 40 to 50m （the maximum injection distance）, the maximum effective protection area increases with injection distance for a fire of light risk class, and decreases for the fire of other risk classes.