Influence of Tube′s Inner Diameter on Interior Trajectory for Underwater Vehicle Ejection Launcher

To balance launch efficiency and size of an underwater vehicle launcher and design proper inner diameter of the launching tube, the many-to-many interface scheme is adopt to overcome the simulation difficulty of gapless slipping between the walls with holes, and a simulation model for solving coupled unsteady flow field, piston and vehicle movement is built. Interior trajectory simulation with different tube′s inner diameters is accomplished by secondary development in software Fluent, and the calculated flow fields as well as the movement time history curve are analyzed. Simulation results reveal that the inner diameter of the tube shows obviously positive correlation with the launching efficiency within a certain scope, while the influence of the inner diameter gradually weakens as the inner diameter increases, and finally the out-tube efficiency tends to be stable. It is concluded that the simulation of underwater vehicle launcher based on many-to-many scheme is reliable, and may be applied to design of underwater vehicle ejection launcher.