Numerical study on the influence of venting interlayer structure on the explosion venting effects

Abstract

Catering is an important business format of commercial complexes in Chinese Mainland, and most of its kitchens use natural gas as fuel. However, once natural gas leaks, it is very easy to cause explosion accidents. For kitchens without external windows in large commercial complexes, the horizontally arranged explosion venting interlayers should be installed to lead the explosion vents from the kitchens to the exterior walls of the buildings. The paper conducts modeling research on linear and 90° bend, as well as interlayers containing structural beams (obstacles), and obtains the explosion propagation laws of different explosion venting interlayer structures. After the flame enters the venting interlayer, the presence of obstacles can cause flame acceleration; the peak pressure in the kitchen shows an increasing-sudden decreasing-increasing trend as the distance between obstacles and the explosion outlet decreases. When the obstacle is located 2.5 m away from the interlayer inlet, the maximum flame propagation speed can reach 356.5 m/s. The effects of the bend structure on the propagation process of gas explosion venting have been investigated. The peak overpressure of 90° bend venting interlayer is 1.52 times that of the linear interlayer. However, there is a notable reduction in peak overpressure (approximately 26.6%) observed post-bend. Additionally, an increase in the distance preceding the bend results in an initial rise followed by a decline in peak overpressure, while the shock wave attenuation coefficient displays a trend of first increasing and then decreasing.