An algorithm for velocity calculation in close proximity to body surfaces in panel methods

To model incompressible flow over a body of arbitrary geometry when using v ortex methods, it is necessary to construct an irrotational field to impose the impermeability condition at the surface of the object. In order to ach ieve this impermeability, this paper uses a boundary integral equation base d on the single-layer representation for the velocity potential. Specifical ly, we formulate this exterior Neumann problem in terms of a source/sink bo undary integral equation. The solution to this integral equation is then co upled with an interpolation procedure which smoothes the transition between near-wall and interior regimes. We describe the numerical scheme embedding this strategy and discuss its accuracy and efficiency. For validation purp oses, we consider the potential and vortical flow over a circular cylinder, for which an analytical solution and the commonly used method of images ar e available.