Experimental investigation of hydrogen jet flame inhibition by nitrogen jet

With the rapid development of hydrogen energy and the increase of the risk of hydrogen jet fires, a reliable fire protection technology is required to extinguish hydrogen jet flame efficiently. An experimental investigation was carried out to study the inhibition of a hydrogen jet flame by a nitrogen jet. The impact angle, nozzle diameter and nozzle position of the nitrogen jet were the variables. The flame characteristic parameters were analyzed, including the flame length, deflection height and deflection angle. The results show that the inhibited flame length was always positively correlated with the vertical distance between the nozzles. The increase of the impact angle had a significant inhibitory effect on the flame length. Besides, the explanatory factor was used to describe the influence of various initial release conditions on flame inhibition and was calculated by the combination of the explanatory variables, such as impact angle, impact stroke and impact height. The flame length reduction ratio, deflection height reduction ratio and dimensionless deflection angle are positively correlated with the explanatory factor. It means that the jet flame is more easily extinguished under a larger explanatory factor. The critical parameter of the explanatory factor for extinguishing the hydrogen jet flame was verified experimentally.