An adjoint method for design optimization of ship hulls

We present a design optimization method for reducing the wave resistance (drag) of surface piercing hulls. Since this component of the drag is directly related to the energy contained in the wave structure that extends behind the ship, a fully coupled calculation of the flow field and wave evolution equation is required. The method combines the authors’ efficient automatic shape optimization technique based on control theory, and non-linear free surface solver. In this approach an evaluation of the gradient of a cost function is computed by solving an adjoint system of partial differential equations, which enables to account for an arbitrary number of design variables (degrees of freedom).