Ignition method and periodic pulse in two-stage pulse detonation engine(PDE) were computed by numerical simulation. Results showed that two zones with high temperature and high pressure were engendered by shock wave imploding in engine. Temperature and pressure of the second zone became much higher than the first one

which was the key point of ignition. Depending on temperature

pressure or Mach number improvement

detonation appeared in the unfired condition. With precondition of successful ignition

modulating was still necessary to get appropriate inlet condition which can keep periodic pulse. Periodic pulse with frequency of 300Hz appeared by the inlet temperature of 600 K

Mach number of 2.0 and pressure of 150kPa.