Advances in Cartesian-grid methods for computational ship hydrodynamics

Recent developments in computational fluid dynamics are enabling accurate simulations of full scale ship hydrodynamic flow. In particular, Cartesian-grid techniques such as volume-of-fluid and immersed boundary methods expedite computational simulations of unsteady breaking wave flows around complicated ship geometries. However, there are still a number of important numerical and modeling issues to overcome such as finite computational domains, moving bodies, and dynamic slip conditions which are required in order for Cartesian-grid methods to achieve their full potential as a practical analysis tool. Additionally, systematic studies of the accuracy and applicability of numerical techniques are key for their use in quantitative engineering applications. In this work we develop a new method for the enforcement of general boundary conditions on an arbitrary body as well as a new exit condition to allow for significantly smaller domains and a volume of fluid algorithm to preserve the free surface characteristics. We consider a number of canonical problems to establish quantitative comparisons and assessments of these new methods. We use these new capabilities to preform flow simulations with naval applications and compare them to experimental results.