VARIATION OF ASYMMETRIC SIDE HULL OF PENTAMARAN HULL RESISTANCE BY COMPUTATIONAL FLUID DYNAMICS (CFD)

摘要

Fast vessel technology is rapidly developing with the increasing of the demands in maritime field such as military, shipping and tourism. The substantial of designing fast vessel is to create a vessel with highest speed and lowest fuel consumption. Ship hull optimization is one of methods to reduce fuel consumption in designing the high-speed vessel. The advantages of multihull vessel are huge payload, wide deck area, good stability and seakeeping, also decrease the total resistance due to wave making resistance caused by wave interference of the hulls. Multi-hull vessel is divided by number of hulls which are catamaran, trimaran, quadramaran and pentamaran. In a research by Tuck (1998) shows that the wave resistance of quadramaran is relatively decreasing at the high speed. Thus, this matter tends to appear the curiosity regarding wave resistance of pentamaran at the high speed. Pentamaran is a kind of ship which has a main hull, two inner and outer side hulls. This research aims to show the configuration effect of pentamaran ship on resistance coefficient by conducting simulation at Froude Number 0.1-1. Computational Fluid Dynamics (CFD) method performed to predict the resistance of hull-form configuration. In this research, the calculation of pentamaran hull resistance is simulated by ANSYS - FLUENT (CFD Software Package). The multiphase region is separated by defining boundary air inlet as the flow of air and water inlet as the flow of water. The free surface model is performed in calm water condition by Volume of Fluid (VOF) model and k-epsilon is used to simulate the turbulent viscous model. The validation data obtained from the Computational Fluid Dynamics (CFD) method were found almost similar with latest pentamaran experimental data. There are two main components of resistance coefficient which dominate the value of total resistance coefficient on pentamaran ship, those are coefficient wave pressure resistance and coefficient viscous resistance. The result shows that waveform resistance coefficient has more contribution in reduce or raise the value of total coefficient resistance.