An Isogeometric Bem for Exterior Potential-flow Problems around Lifting Bodies

In this paper, the Isogeometric Analysis (IGA) concept is combined with the Boundary Element Method (BEM) for solving the exterior Neumann problem associated with the steady lifting flow around a hydrofoil. The formulation of the problem is based on a Boundary Integral Equation for the associated velocity potential combined with the null-pressure jump Kutta condition at the trailing edge. The developed IsogeometricBEM is based on a parametric NURBS representation of the hydrofoil and employs the very same basis for representing the velocity potential. The Boundary Integral Equation is numerically solved by collocating at the Greville abscissas of the knot vector of the hydrofoil’s parametric representation. Numerical error analysis of the Isogeometric-BEM using h-refinement is performed and compared with classical low-order panel methods.