Explosion characteristics of dimethyl ether/air/argon mixtures

Explosion characteristics of dimethyl ether (DME)/air and DME/air/ argon (Ar) mixtures were studied by using a 20-L spherical explosion-containment vessel under different initial conditions. This paper analyzed the effects of different initial conditions (e.g., pressures, Ar dilution) on the explosion parameters including explosion limits, maximum explosion pressure and maximum rise rate of explosion pressure. A dome-shaped relationship was found between maximum explosion pressure and DME concentration. And there lies a dome-shaped relationship between maximum explosion pressure rise rate and DME concentration. Their maximum values appear in the vicinity of the stoichiometric composition. Lowering the initial pressure can significantly decrease the upper flammability limit, but has no influence on the lower explosion limit. For fuel-rich DME/air mixtures, Ar dilution can greatly decrease the maximum explosion pressure and the maximum rise rate of explosion pressure. For fuel-lean ones, in a certain range of Ar concentration, the maximum explosion pressure and the maximum rise rate of explosion pressure increase with the increasing of Ar concentration. And these explosion parameters decrease eventually with the increasing of Ar concentration over 20%. ©, 2015, Explosion and Shock Waves. All right reserved.