To improve two-stage pulse detonation engine's operational reliability

a method of enhancing detonation initiation via shock wave focusing was explored. Numerical simulation was conducted

hydrogen was used as a fuel and air as an oxidizing agent. Influences of 3 outlet surface shapes and various exit areas on shock wave focusing were discussed. Results indicated that vertical outlet surface was helpful to increase the pressure and temperature of shock wave focusing and make it occur ahead of focusing time. Pressure of focusing point increased as exit area decreased. Tilting outlet surface was inferior to vertical outlet surface

pressure and temperature of focusing point increase little. Curved exit surface was not helpful to increase the pressure and temperature of shock wave focusing

and detonation wave was not initiated. Compared with 3 outlet surface shapes

vertical outlet surface was better. Simulation results provided a reference for experiment design.