Numerical Study on Pulsed Jet Coupling Effect and Projectile Pitching Motion

The pulsed jet with direct force control can provide a fast and environment-free control scheme. However, a complex jet interference occurs during the establishment and decay of the pulsed jet. The continuous working of the pulsed jet also has a strong coupling effect with the projectile’s attitude motion. All these make it necessary to study the influence of the projectile pitching motion on the pulsed jet interference. Based on numerical simulations, this study investigates the development of complex flow structures within pulsed jets during pitching motion, explores the flow mechanism that governs the motion of projectile under continuous excitation from single or multiple jets, and characterizes the interference patterns of intermittent jets on the projectile body and tail wings. It is concluded that during the initial establishment of the flow field, the intensities of the upstream separation region, downstream low-pressure region, bow shock wave, and barrel shock wave from the pulsed jet interference flow field are all weaker than those observed in the steady jet interference flow field. Changes in the projectile’s pitch rate have a relatively minor impact on the interference flow field introduced by a single-nozzle pulsed jet. In addition, when the axially arranged dual nozzles are activated in a timed sequence, the sequential activation and deactivation of adjacent nozzles can lead to the superposition of interference effects.