On the motion of a rigid body in a two-dimensional ideal flow with vortex sheet initial data

Abstract

A famous result by Delort about the two-dimensional incompressible Euler equations is the existence of weak solutions when the initial vorticity is a diffuse bounded Radon measure with distinguished sign. In this paper we are interested in the case where there is a rigid body immersed in the fluid moving under the action of the fluid pressure. We succeed to prove the existence of solutions \`a la Delort in a particular case. These solutions satisfy the energy inequality and the body acceleration is bounded.