Attenuation of the detonation wave in hydrogen–air mixture

Abstract

The deceleration and attenuation of a detonation wave in hydrogen-air mixture was experimentally studied in a cylindrical channel. Inner walls of the wide section of the channel were covered with an acoustically absorbing layer. Experiments were carried out in hydrogen-air mixture at atmospheric pressure. Initially detonation was formed as a result of a deflagration to detonation transition. The dependence of velocity and pressure at the front of the detonation or shock wave on the thickness of the acoustically absorbing material and mixture composition (equivalence ratio) was presented. The results demonstrate that increasing the thickness of the porous material on the walls lead to further attenuation of the detonation wave to the point where it is not re-initiated at the distance of 15 calibers from the porous section. It was found that the recovery of the detonation wave after the passage of the acoustically absorbing section can happen if the shock wave velocity does not drop below Chapman-Jouguet acoustic velocity.