Flame behavior and pressure characteristics of vented propane-air explosions

Abstract

Flame behavior and pressure characteristics of vented propane-air explosions in a narrow duct were studied by changing equivalence ratio (φ), venting diameter (Dv) and venting position. As the equivalence ratio increased from below to above unity, the maximum reduced pressure (Pred) showed different trends for the two fixed sizes of Dv. With the Dv increasing from 60 mm to 210 mm, the discharge efficiency presented a logarithmic increase, and increased slowly after reaching the inflection point where the non-dimensional vent coefficient KV was 49. As the distance d between the venting position and the ignition source increased, the Pred first increased and then decreased, and reached the minimum when the venting position of a narrow duct was d/L = 0.9. The predicted results of the international applicable standard were compared with the experimental results, and an empirical model of Pred was established by introducing the non-dimensional vent coefficient KV and the distance d from the venting position to the ignition source. As an extension of the applicability of standards, it would provide a reference for venting safety design in practical engineering applications.