Simulation of Inner Trajectory Flow Field for Pneumatic Imbalance Torpedo Launcher

In order to directly describe the inner chamber pressure and the distribution of torpedo exit velocity, this paper builds a inner flow field model of torpedo launcher, and performs a numerical simulation based on the dynamic mesh technique of the software Fluent. Simulation result shows that the pressure distribution varies in launcher when torpedo moves in it. At beginning of launch, the pressure gradually gets lower from entrance of launcher due to throttling within the annular gap of torpedo and launcher. But with torpedo moving and the annular gap increasing, the pressure in the back section of launcher bacomes equal to the pressure at the unilateral valve entrance, and the pressure at torpedo tail is always less than the entrance pressure.