氮气幕对瓦斯爆炸进行阻爆实验

为阻断瓦斯爆炸在管道方向上的传播，保护管道后方区域，本文采用氮气幕来进行阻爆，所设计的实验装置在爆炸发生后能自动喷出氮气。主要研究了氮气的喷气压力和喷气时刻对阻爆功能的影响。结果表明，在喷气压力为0.1MPa时，氮气幕仅起到抑制作用，爆炸火焰能穿过整个实验管道。在喷气压力为0.2MPa时，仅部分实验能够阻爆，氮气幕产生不稳定的阻爆效果。在喷气压力为0.3MPa时，阻爆位置均稳定在左喷头和右喷头之间区域，氮气幕产生稳定地阻爆效果。喷气压力超过0.4MPa后，阻爆位置稳定在右喷头附近。在较低氮气压力0.2MPa下，喷气时刻对阻爆效果产生显著影响。随着喷气时刻延迟，氮气喷出量减小，氮气幕由不稳定阻爆变为不阻爆。喷气时刻延迟到198ms后，氮气幕便丧失阻爆功能。在喷气压力超过0.3MPa后，氮气幕阻爆效果便不受喷气时刻的影响，喷气压力对能否阻爆起决定作用。

Experimental on the prevention of gas explosion by nitrogen curtain

In order to stop the propagation of gas explosion along the duct and to protect the downstream area of the duct, the nitrogen curtain is adopted to prevent the explosion. The nitrogen can automatically be spurted out by the designed experimental apparatus after the occurrence of explosion. In this paper, the effect of nitrogen pressure and spurting moment on the prevention of explosion was studied. The results showed that when the nitrogen pressure is 0.1MPa, the nitrogen curtain only has the effect of suppression. The explosion flame can spread through the whole duct. When the nitrogen pressure is 0.2MPa, only part of the experiments can prevent the explosion. The nitrogen curtain has an unstable effect of prevention of explosion. When the nitrogen pressure is 0.3MPa, the preventing position is stable between the left nozzle and the right nozzle. The nitrogen curtain is stable on the prevention of explosion. When the nitrogen pressure exceeds 0.4MPa, the preventing position is stable at the right nozzle. At the lower nitrogen pressure of 0.2MPa, the nitrogen spurting moment has a significant effect on the prevention. With the delay of spurting moment, the magnitude of spurted nitrogen decreases. And the nitrogen curtain changed from unstable prevention to failure of prevention. When the spurting moment delays 198ms, the nitrogen curtain will lose the ability of the prevention of explosion. When the nitrogen pressure is larger than 0.3MPa, the preventing effect of the nitrogen curtain will not be affected by the spurting moment. The nitrogen pressure can be a decisive role in the prevention of explosion.