Abstract
A modified Rankine source method is proposed, where the free surface condition is linearized based on the viscous-double-hull flow and the hull surface condition is approximated to be satisfied only by the double-hull potential. The flow field is represented by Rankine sources distributed over the free surface.
Preliminary pilot computations for 2-D and 3-D point sources are carried out in the first place in order to establish the computation scheme. Then the availability of the present method is exemplified by computing the free surface flows and the wave elevations of M-21 and Wigley model whose hull forms are so simple that their double-hull flows can be prepared with least numerical errors. In this first report we confine ourselves to the inviscid case.
The higher approximation for the discrete source density is certified to be significant. The employment of the approximation for the hull-surface condition decreases both computing time and memory storages so much that the present method is promising for practical purposes. Free surface flows and wave elevations are well reproduced as far as the two models are concerned.
