Influence of Gradually Inflated Obstructions on Flame Propagation in a Tube Closed at One End

Rapid suppression is a must in the mitigation of ventilation air methane (VAM) explosions. Flame proves to be much more challenging than prevention flame initiation due small physics timescale (~1 s). This study numerically investigates effect spherical obstructions on propagation dynamics tube closed at one end. Obstructions with an inflating geometry, installed different locations, were examined. Noticeably, presence single or multiple that partially block tube, and pressure waves propagate faster upstream empty tube; this phenomenon pronounced when obstruction located further away from ignition point. In scenarios full blockage high builds up inside blocked region, e.g., surging 7.5 bar less 0.1 s location 10 m point (tube diameter: 0.456 m). closer experience tearing terms duration strength.