关于回燃前重力流的盐水模拟实验研究

An experimental study on salt water modeling of gravity currents prior to backdrafts

为了研究建筑火灾中特殊火行为———回燃前重力流的速度特征 ,几何特性及其混合层范围 ,本文做了一系列的盐水模拟实验 ,实验腔体 (0 .4m× 0 .1m× 0 .1m)的端面可装配有不同的开口形式 :全部开口、中间开口、上边开口、下边开口、门开口和窗开口 ,以模拟建筑物中各种形式的形状、位置及大小 ,实验结果表明盐水模拟回燃前的重力流具有与一般的重力流相似的特征 ,盐水模拟实验可以很准确的模拟回燃前重力流的运动情况 ,也可以预测不同开口形式的腔体产生回燃的时刻。

In order to investigate the velocity profiles, geometrical characters and mixing range of the gravity currents prior to backdrafts in building fires, a series of salt water experiments were conducted. The compartment (0.4m×0.1m×0.1m) was fitted with a variety of end openings: full, middle-slot, upside-slot, downside-slot, door and window openings. The experimental results indicate that the gravity currents in salt water compartment are similar to general gravity currents in nature, and the experiment can be employed to model the moving characters of gravity currents prior to backdrafts and predict the time of ignition for backdrafts in compartments with various opening geometries.