Design of fault diagnosis system for pulse detonation engine

In order to explore the stable operating mechanism and operating boundary conditions of PDE, a failure diagnosis system was designed in this study. The inputs of the failure diagnosis system are as follows: engine control signals of the igniter and the solenoid valve, pressure signals and flame ion current signal of the detonation chamber, flow signal of the high-frequency flow-meter of the fuel and oxidizer channel. In each ignition cycle, the equivalence ratio of engine, the mixing time of fuel and oxidizer, the characteristics of the solenoid valve, the propagation speed of the combustion wave, the pressure of the detonation chamber, and other characteristic signals are accurately analyzed to obtain the engine operating status and the cause of the failure. In each second, statistics of the total number of engine ignitions, detonation success rate, and failure diagnosis results are implemented, then the statistical results, i.e., the signal waveforms and characteristic parameters of each ignition cycle, are transmitted to the human-computer interaction unit display. As a result, the engine operating parameters are visualized, the efficiency of failure diagnosis and operating boundary conditions exploration is improved.