Experimental investigation about the influence of gas concentration on flame propagation

In order to investigate the influence of concentration on gas explosion and flame propagation characteristics in long and straight pipe, experiments about gas explosion were performed with and without obstacles in duct, and a high speed camera was used to reveal the process of flame propagation. Results indicate that flame experiences many oscillations in closed pipe, which is caused by the turbulence of unburned gas induced by the compressive wave in front of the flame. Gas concentration greatly influences on the maximum flame velocity and the maximum propagation distance. Obstacles can accelerate flame and flame propagates fastest when gas is close to stoichiometric concentration, and deflagration to detonation transition may occur under certain conditions. ©, 2015, Beijing Institute of Technology. All right reserved.