Boundary-Integral Computation of Hydrodynamic Interactions Between a Three-Dimensional Body and an Infinitely Long Cylinder

Hydrodynamic interactions between a three-dimensional body of revolution and an infinitely long circular cylinder in an inviscid fluid are studied numerically by the boundary-integral method. The added-mass coefficients and their derivatives are computed in terms of the solutions of four integral equations of the second kind. A numerical technique based on variable transformations is developed to evaluate integrations over steep peaks. Integrations over the cylindrical surface are properly computed by mapping the infinite region onto a finite region and regularizing the ill-behaved kernels with sharp peaks. The discrete added masses and their derivatives are fitted by the least-squares approximation on the basis of Legendre polynomials. As a practical example, the moving trajectories of a sphere conveyed by a uniform flow around a fixed circular cylinder are computed and presented.