NUMERICAL MODELING OF FLOW AROUND CATAMARAN VESSEL AND CALCULATION OF HYRODYNAMIC RESISTANCE BY COMPUTATIONAL FLUID DYNAMICS

Calculation of hydrodynamic resistance is one of the most important steps in design of vessels. Nowadays، using numerical methods and specially Computational Fluid Dynamics (CFD) for calculation of ship resistance is one of marine engineering fields. In this research، flow around the hull of a catamaran vessel is investigated numerically and resistance is calculated. Numerical modeling is done with FLUENT CFD code. This software solves governing equations by Finite Volume Method (FVM). Modeling is carried out for two ratios of separation to length of vessel (S/L) and finally numerical results are compared to experimental results from model tests. At low speeds، numerical results have a good agreement with experimental results but in higher speeds، the difference between numerical and experimental results increases about 10-20%. Also، by the increase of hull separation، the total resistance of catamaran decreases due to reduction of demi-hulls interferences.