Investigation of hydrodynamic characteristics of high speed multihull vessels including shallow water fffect

The objective of this paper is to investigate the hydrodynamic characteristics of high speed catamaran and trimaran ships at different speeds and finite depths using Computational Fluid Dynamics (CFD) techniques. Three dimensional Rankine Source Panel Method with non-linear free-surface boundary condition is used to capture free-surface potential flow around ship hull. Wave pattern, wave resistance, sinkage and trim for varying lateral and longitudinal separation of hull with varying water depths are determined and compared with each other to investigate spacing and depth effects on multihull ship. Computed results show a significant increase in total resistance for water of finite depth compared to deep water. A significant increase in sinkage and trim has also been found in the case of shallow water for both vessels.coupled with RANS solver is used to compute propeller open and self propulsion characteristics at different positions of rudder. Verification and validation studies for resistance coefficients have also been carried out using ITTC recommended procedure. The present computational method reveals that CFD results of flow field around ship hull with propeller and rudder effects are prospective and can be successfully applied in maritime industry.