سعید جامعی

The main advantage of submarine vehicles than other ships, is ability to navigate at different depth. There are three position sailing range for submarine consist of deep water, near surface and free surface. There are different ways to solve hydrodynamic parameters, Nowadays, computational fluid dynamics are used as a powerful tool for hydrodynamic optimization of marine vehicles. At this thesis, the goal is to simulate and calculate the hydrodynamic parameters of 4 submarine models in three sections such as deep water, near to the free surface and on the free surface using the Star ccm software. To ensure the accuracy of simulating numerical models, First the total coefficient of resistance of the sub-model is calculated using computational fluid dynamics tool and verify with experimental total coefficient of resistance Which was done by Haffenden. In the deep water condition, the velocity distribution around the submarine body is checked. According to the there are curvature at the fore and aft submarine body, the Reynolds number method can not predict the type of fluid flow around the body, because the pressure of the fluid is not the same as the atmosphere along the submarine body. In order to study the velocity distribution, transverse sections are considered at certain intervals along numerical models and the rate of velocity changes is calculated in the boundary layer boundary. Typically, in the aft region of submarine, due to the viscosity of the fluid properties, the fluid flow decreases and generates a vortex, which causes the wake to be calculated for 4 submarine models at different velocities of the velocity and wake gradient around the aft region of submarine. When a body moves on the surface with near surface, it produces waves on the free surface. The production wave is a function of the characteristics of the fluid, the geometry and the motion of the object. Length, height, and other characteristics of the production wave can be used to identify sub