Effects of hollow cylindrical charge with one end initiation on driving characteristics of a discrete rod

By changing hollow diameter of cylindrical charge with one end initiation, its detonation output characteristics and influences on driving characteristics of a discrete rod were studied. Numerical simulations of discrete rods' detonation driving processes were performed with the nonlinear dynamic analysis program LS-DYNA and the fluid-solid interaction method. The influences of different hollow diameters on pressure distribution of detonation products, velocity, micro-unit velocity distribution and effective length of discrete rod were analyzed. The simulation results showed that with increase in hollow diameter, gradually enhanced sparse effects make the pressure along the axial direction tend to the same; the resultant velocity of the discrete rod decreases nonlinearly with increase in hollow diameter and the micro-unit velocity gradient also decreases; the larger the hollow diameter, the better the flatness of the rod, while the flatness has a reverse variation to the velocity of the rod; so the optimal effect of the discrete rod should consider the balance between its velocity and flatness.