A two-dimensional potential model with vorticity release is developed in order to investigate the self propelled swimming of undulating bodies. The body is free to move not only in the forward and lateral directions, but it can also rotate around its center of mass, according to the forces and moments induced by the flow field generated by its own prescribed undulation. The numerical model is based on an unsteady potential panel code for deformable bodies. The vortex shedding process is modeled by an unsteady Kutta condition. The model is able to predict the full kinematics of the undulating foil by expressing forces and moments in terms of hydrodynamic impulse. To study a body in self-propulsion immersed in an otherwise quiescent fluid, a complete body-fluid system has to be taken into consideration with a particular attention to the exchange of internal forces. The intention is to use the simplified model for an ambitious objective: clarify the role of the added mass and of the vorticity release in the free swimming either for the initial starting accelerations and for the velocity to be reached at steady conditions.
