Numerical Simulation of Free Surface Affected by Submarine with a Rotating Screw Moving Underwater.

We conducted a numerical simulation of the free surface affected by the diving movement of an object such as a submarine. We have already proposed a computation method that combines the moving grid finite volume method and a surface height function method. In this case, the dive movement was expressed only as a traveling motion, not as a deformation. To express the deformation of a body underwater, the unstructured moving grid finite volume method and sliding mesh approach are combined. The calculation method is expected to be suitable for a computation with high versatility. After the scheme was validated, it was put to practical use. The free surface affected by a submarine with a rotating screw moving underwater was computed using the proposed method. Owing to the computation being for a relatively shallow depth, a remarkable deformation of the free surface occurred. In addition, the movement of the submarine body had a more dominant effect than a screw rotation on changing the shape of the free water surface.