网状金属材料对火焰波阻隔作用的实验研究

Experimental Study on the Blocking Effect of Mesh Metal Materials on Flame Wave

为了研究网状金属材料对火焰波的阻隔作用,设计了可架设阻隔材料的气体爆炸箱,借助高速摄像机及ProAnalyst软件,测定了不同点火位置、不同网状金属材料条件下的气体爆炸后火焰波运动状态,进而分析了网状金属材料在该条件下对火焰波的阻隔作用。实验表明:在无阻隔物时,气体爆炸后的火焰波以球形向四周传播,其速度趋势呈抛物线形变化,存在一个速度的峰值;设置阻隔物后,火焰波遇阻隔物发生形变,垂直于阻隔物方向速度峰值降低,但同时水平方向传播速度加快,阻隔物距离点火源越近,这些现象越明显;在相同点火距离下,对于不同金属的阻隔物,火焰波垂直方向传播速度及其峰值以及到达峰值的时间与材料的导热系数具有负相关性。可见,从位置上看,阻隔物靠近点火源,可以有效阻隔垂直火焰波;从材料上看,选择导热系数大的金属阻隔材料,不但可以有效阻隔垂直火焰波,还可以使阻隔作用提前,起到双重的阻隔效果。

In order to study the blocking effect of mesh metal materials tin the combustible gas flame wave, the gas explo- sion box is designed to set barrier materials. The flame wave motion state with the different metal barrier and the different ig- nition positions is observed by speed cameras and ProAnalyst software in order to analyze blocking effect under these condi- tions. The experiments show that the flame wave spreads as spherical without barrier, and its speed changes in parabolic shape; while the barrier is set, the shape of the flame wave would be changed, the peak velocity is reduced in the vertical direction, and increased in the horizontal, the closer between barrier and ignition position, the more the change is; the peak velocity of the vertical direction and the time of arrival is negatively correlated with the thermal conductivity of different mate- rials. So the barrier near the ignition could effectively cut off the flame wave in the vertical direction and the material of higher thermal conductivity could not only block the vertical flame wave effectively, but also accelerate the blocking effect.