BOUNDARY-INTEGRAL COMPUTATION OF HYDRODYNAMIC INTERACTIONS BETWEEN A 3-DIMENSIONAL BODY AND AN INFINITELY LONG CYLINDER

Hydrodynamic interactions between a three-dimensional body of revoluti on and an infinitely long circular cylinder in an inviscid fluid are s tudied numerically by the boundary-integral method. The added-mass coe fficients 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 integration s over steep peaks. Integrations over the cylindrical surface are prop erly computed by mapping the infinite region onto a finite region and regularizing the ill-behaved kernels with sharp peaks. The discrete ad ded masses and their derivatives are fitted by the least-squares appro ximation 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.