Numerical Study of Submarine Launched Underwater Vehicle

Launching of underwater projectile from submarine is carried out by gas-steam ejection dynamic system. Specific velocity of projectile at water exit is essential for its successful launch. The velocity of projectile depends upon the projectile dimensions, mass and water depth which govern the pressure requirements for gas-steam ejection dynamic system. To investigate the pressure required to launch the projectile under various conditions, a two-dimensional, axisymmetric numerical model was established. The numerical simulations were performed using ANSYS Fluent software. Dynamic mesh method was applied to track the motion of projectile combined with a User Defined Function (UDF) to compute the forces exerted on the body of the projectile. To achieve specific exit velocity of projectile for number of cases by varying vehicle mass, nose shape, and water depth simulations were performed and corresponding pressure requirements for each case was determined. Results shows the nonlinearity in pressure requirements with changing different parameters to achieve same exit velocity. In addition, bubble cavity formation in water is analyzed.