Numerical investigations on interaction of implosion flame with shock

Based on the two-dimensional axisymmetric Euler equations coupling with chemical reactions, the phenomena of implosion wave in the inertia medium and interaction of the implosion flame with shock in the hydrogen-air mixture were numerically studied by using wave propagation algorithm with monotonized centered (MC) limiter in the cylindrical tube with two open ends. In the inertia medium the simulations show that toroidal shocks implode and reflect at the axis of symmetry of the cylindrical tube. Every implosion can form a Mach stem that propagates towards the previous Mach stems, which enhances shock but decreases in the whole because of absence of energy. In the hydrogen-air mixture the calculated results show that shock induced by combustion repeatedly interacts with implosion flame in the cylindrical tube, which leads to the fact that frequency and intensity of Mach stems at the axis of the cylindrical tube are higher than these in the inertia medium. Simultaneously, repeated shock-flame interactions cause instability and distortion of the flame, and then form the shape of collapsing flame front.