Preventing the propagation of gas explosion in ducts using spurted nitrogen

This study discusses the use of nitrogen to prevent the propagation of an explosion in a horizontal duct in an effort to reduce the damage caused by gas explosions. Accordingly, the vent is set on the top surface of the duct. The two nitrogen nozzles are set near the vent and at a downstream location. The results show that when the nitrogen pressure reaches or exceeds 0.3 MPa, spurting nitrogen can prevent the explosion from propagating along the duct. When the nitrogen pressure is 0.1 MPa, it fails to prevent the explosion. When the nitrogen pressure is 0.2 MPa, the explosion propagation can be prevented in most experiments but not in all of them. As the nitrogen pressure increases, the position for preventing the explosion gradually shifts forward from the second nozzle to the first nozzle. At lower nitrogen pressures (i.e., 0.2 MPa), an early spurt of nitrogen can prevent the explosion, while a delayed spurt of nitrogen may not be able to prevent it. The distribution of the speed of the explosion flame along the duct exhibits two peaks. The regularity of the overpressure is similar to that of the flame speed. (C) 2018 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.