Interaction mechanism of wire mesh inhibition and ducted venting on methane explosion.

• Interaction mechanism of wire mesh inhibition and ducted venting was analyzed. • Pressure showed an uptrend with increasing initial pressure and ignition energy. • The P max was increased gradually with the increases of the mesh number and layer. • The critical condition for the complete inhibition of venting flame was determined. • The negative pressure inside the vessel during explosion venting was explained. A set of experimental equipment for wire mesh inhibition and ducted venting on methane explosions was proposed. The effects of wire mesh parameters, venting parameters, and initial conditions on the explosion intensity were also investigated and the interaction mechanism between the wire mesh inhibition and ducted venting was analysed. The results indicated that the venting flame length decreased gradually and the explosion pressure inside the vessel increased with increasing wire mesh number and layer. Especially the venting flame did not appear outside the vessel under the five layers and 60 mesh number condition, which indicated that the explosion flame propagation was effectively inhibited by the metal wire mesh. With an increase in the venting diameter, the maximum explosion pressure (P max) inside the vessel decreased gradually. However, the P max and the maximum pressure rise rate ((dP/dt) max) were increased with an increase in the rupture pressure, and the appearance moment of the P max was decreased. The initial concentration, initial pressure, ignition energy and venting position as the important factors could evidently affect the combined effects of wire mesh inhibition and ducted venting for explosion protection. The P max inside the vessel first increased and then decreased with an increase in the methane concentration, and the explosion intensity was the highest under the equivalence ratio condition. With an increase in the initial pressure and energy, the P max also was increased. The pressures at the vessel and duct end under the vessel top venting were greater than that of duct end venting. [ABSTRACT FROM AUTHOR]