And fin stabilizer effect

Abstract

A semi-SWATH ship is a high ship speed as a hybrid design of catamaran and SWATH (Small Waterplane Area Twin Hull) design. The ship has a lack of tending to a bow-dive condition when running in wave high in following sea. The slender and low buoyancy force at the bow hull causes the tendency of the condition is increase. A parametric study developed to investigate the lack and increase the ship behavior using fixed and active fin stabilizer. A numerical simulation developed for 3DoF (surge, heave, and pitch) based on strip theory, and validated using seakeeping test in towing tank. The simulation found the ship with fixed fin at bow-dive condition and then reduced the possibility of immersed foredeck. However, the tendency of immersed foredeck in longer wavelength is increase, whilst the ship with all fixed fin stabilizer.