Burning of local hydrogen-air mixtures in an unsealed vessel containing obstacles

Large-scale experiments are reported on the burning of hydrogen-air mixtures in an apparatus having a reaction vessel of volume 20 m$^3$. A fast-burning mixture (30% hydrogen in air) shows a reduction in the pressure rise rate and in the maximum pressure when the discharge hole is close to the region of local burning. For a slow-burning mixture (10% hydrogen in air), the pressure is reduced when the discharge holes are far from the local burning region. A study has been made on the joint effects of immobile alternating obstacles and gas-dynamic perturbation caused by the motion of the medium towards the discharge holes as regards the intensification of the burning for local hydrogen-air mixtures.