Study on pressure wave response and overpressure attenuation law of explosion-proof doors

In order to evaluate the pressure relief characteristics of the explosion-proof door, experiments were conducted in a self-built small size explosion-proof door experimental platform. The details of pressure changes in the pipeline were monitored in detail through four monitoring points set on the right end of the pipe, horizontal pipe, the main ventilation fan tunnel and below the explosion-proof door. The overpressure attenuation law at different positions and the effect of equivalent ratio on overpressure attenuation were studied when the explosion-proof door was normally opened for pressure relief and failed to open for pressure relief. The results showed that when the explosion-proof door cannot be opened for pressure relief, the overpressure of the main ventilation fan tunnel and the explosion-proof door will increase dramatically. Compared with the normal pressure relief by opening the explosion-proof door, it increased by 130.69 % and 100.36 % respectively. Through the explosion-proof door pressure relief, the overpressure attenuation at the main ventilation fan tunnel and the explosion-proof door exhibited a linear. However, the overpressure attenuation at the main ventilation fan tunnel was the most obvious when the phi = 0.94, and the overpressure attenuation at the position of the explosion-proof door was the most obvious when the phi = 1. With the increase of phi, the time interval between two overpressure peaks at each monitoring point showed a downward trend, and the decreasing trend was more obvious at the main ventilation fan tunnel compared to other monitoring points. It was also noted that the trend of the time interval between the two overpressure peaks at the four monitoring points will gradually stabilize with the increase of the equivalence ratio. Additionally, the peak overpressure decline rate at the explosion-proof door position was always greater than that in the main ventilation fan tunnel. This indicates that the overpressure attenuation effect at the explosion-proof door is stronger than that at the main ventilation fan tunnel.