The Numerical Study On Detonation And Its Suppression In Flammable System

Based on two-fluid model and 2-reaction mechanism, taking account of elementary reactions and two phases momentum or energy exchanging etc, the models for one-dimensional detonation and its suppression by inert particles are established. TVD method and MacCormack scheme are used to deal with gas phase and particle phase equations, respectively. Ronge-Kutta algorithm is adopted to resolve chemical reaction. The stiffness of equations is solved with time splitting technique.With all the methods and techniques mentioned above, the detonation of H₂-O₂-N₂ mixture induced by a uniform hot reactive gas pocket and its suppression by inert dust particle cloud are discussed theoretically and numerically. Flow structural features and the regularity of some vital characteristic parameters variations are focused on. The results show that only when the initial temperature of hot gas is in a suitable scale, can transition process from accelerating combustion to detonation occur. Because of momentum and energy exchanging between gas phase and particle phase, explosions are generally suppressed by inert particle cloud in the following study. The pressure peak and velocity of shockwave is reduced after suppression. The inert dust particle concentration is critical for explosion suppression. It is found that the higher particle concentration is given, the more effective suppression will be. Lightweight particles have stronger effect on explosion suppression than large ones.The mechanisms of flammable gas detonation and its suppression by inert dust cloud are revealed basically in the studies. Some ideas or approaches are put forward to reliability and effectiveness of the explosion suppression system development. The research is essential to industry explosion hazards mitigation and control.