Gasoline Vapor Explosion Modes in Confined Space under Weak Constraint Conditions

The article focuses on the establishment of the experiment system in confined space with weak constraint surface. It also studies the overpressure variation of gasoline vapor explosion, the mechanism of flame shapes with time, and the coupling relationship between them under different weak constraint conditions. Meantime, the development modes of external flame after the damage of weak constraint are categorized. The results show that: 1. With the increasing area of weak constraint surface, the development modes of external flame can be categorized into: under-expansion jet combustion, jet combustion, external explosion. 2. When an external explosion occurs, the change of internal overpressure in confined space is more complicated, with multiple overpressure peaks as well as strong Helmholtz oscillations. 3. Lower initial gasoline vapor concentration and large area of weak constraint surface are more conducive to external explosion.