Modeling and numerical simulations of 3D flows past self propelled fishes

Modeling and simulation of three-dimensional flows past deformable bodies are considered. The incompressible Navier-Stokes equations are discretized in space onto a fixed cartesian mesh. The displacement of self propelled deformable objects through the fluid is computed from the Newton's laws (forces and torques computation) and is taken into account using a penalisation method. The interface between the solid and the fluid is tracked using a level-set description so that it is possible to simulate several bodies freely evolving in the fluid. The application considered is fish-like swimming . Fish maneuvers and propulsion efficiency for different swimming modes for a single fish or for a fish school are investigated.