Added mass of an oscillating hemisphere at very-low and very-high frequencies

STORTI, MARIO; D'ELÍA, JORGE

JOURNAL OF FLUIDS ENGINEERING-TRANSACTIONS OF THE ASME

ASME

Lugar: New York; Año: 2004 vol. 6 p. 1048 - 1053

0098-2202

A floating hemisphere under forced harmonic oscillation at  very-low and very-high frequencies is considered. The problem  is reduced to an elliptic one, that is, the Laplace operator  in the exterior domain with Dirichlet and Neumann boundary  conditions. Asymptotic values of the added mass are found with an analytic prolongation for the surge mode, and with a semi-numerical  computation with spherical harmonics for the heave mode.The general procedure is based on the use of spherical  harmonics and its derivation is based on a physical insight rather than a mathematical one. This case can be used to test the accuracy achieved by numerical  codes based on other formulations as finite or boundary elements.