An experimental study on pressure evolution during closed explosion and venting progress of methane–air mixtures ([CH4=10%]) in linked vessels was performed, for systems at various initial pressures (P0=0-0.08MPa). The effects of initial pressure on regularity of pressure variation in vessels were discussed. For the closed explosion in isolated vessel, the higher level of the initial pressure in isolated big vessel is, the larger the peak pressure and rate of pressure rise is, and the peak pressure increases nonlinearly with initial pressure; For closed explosion in linked vessels, the higher initial pressure within the linked vessels system leads to the higher peak pressures in two vessels and there is an approximate linear relationship between them, which is similar to explosion in isolated vessel. For vented explosion in linked vessels at higher initial pressure, venting has poorer effect on protection of the linked vessels.
