Influence of diaphragm thickness on gas explosion suppression by vacuum chamber

Abstract

In this study, a vacuum chamber is employed as a new method for suppressing gas explosions using a diaphragm, a device that separates the vacuum chamber from a gas pipe. After over-pressurization in the pipe breaks the diaphragm, the vacuum chamber plays a role in suppressing gas explosion. Notably, the performance of the diaphragm significantly influences the way in which gas explosion is suppressed by the vacuum chamber. To perform experiments for testing such effects, this study used the polytetrafluoroethylene films of 0.1mm, 0.2mm and 0.3mm thickness as the vacuum chamber diaphragm. As the diaphragm thickness changed, the suppression effect on gas explosion varied. Vacuum chambers have an obvious influence on the propagation characteristics of explosion flame. When explosion flame spreads to a nearby vacuum chamber, the flame signal weakens, flame speed decreases, and flame thickness increases. Vacuum chambers can distinctly weaken an explosion's overpressure and impulse. The thinner the diaphragms, the greater the change in explosion flame parameters and the smaller the explosion overpressure and impulse. When using a thinner diaphragm, at the point at which the diaphragm disintegrates, the distance between the explosion flame front and vacuum chamber decreases, thereby increasing the explosion's flame stretch. Thus, the thinner the diaphragms, the better the overall explosion suppression.