Experimental Study of the Non-equilibrium Explosion Venting in Spherical Vessel

Explosion venting offers overpressure protection from potential industrial explosion hazards. This work experimentally studied the non-equilibrium explosion venting of methane-air mixtures in 22L and 110L spherical vessels, under various venting areas and pressures. The results showed that venting area had an obvious influence on explosion venting pressure and the small venting area can hardly protect the vessel from the explosion hazards. When A/V^2/3 is less than 0.00855, pressure will rise after explosion venting and there is linear relationship between the maximum explosion venting pressure and venting pressure. When A/V^2/3 is bigger than 0.025, it is near to the equilibrium venting and independent on the venting pressure. When the A/V^2/3 is up to 0.016, abnormal overpressure occurs under 0.1353 MPa venting pressure. For unconstrained explosion venting, P_red in 22L and 110L spherical vessels is equal and (dP/dt)_max accords with Cube-Root law for venting in the same A/V^2/3. The prediction curves of (dP/dt)_max vs V^1/3 for unconfined vent different A/V^2/3 and the prediction curves of P_red vs venting pressure under different A/V^2/3 are provided.