Time-domain simulations and measurements of loads and motions of planning high-speed craft in waves

摘要

A 2-dimensional non-linear time-domain simulation model tailored for planing hulls in head seas, is presented together with results from model experiments, studying motional response and hull pressure distribution. A wave equation representation of the wave measurement is used in the numerical simulations enabling direct comparisons between simulated and measured time series. Compared quantities are heave and pitch motions; accelerations at bow and centre of gravity; and simulated section loads compared with integrated section wise pressure measurements. It is concluded from the measurement results that the difficulties to model planing calm water performance, noticed by many authors, are above all due to the flow at transom. It is also shown that with a simple correction of the excitation force close to the stern the performance of the simulation model is improved in calm water as well as in waves. The modified simulation model accurately repeats all measured quantities also at severe wave conditions when the hull occasional leaves the water and reenters with the characteristic slamming response all along the hull.