In the present study, we conducted propeller open water test, resistance test, and propeller, ship hull interaction for a ship"s resistance and propulsion performance, using computational fluid dynamics techniques, where a K-epsilon, K-omega turbulence viscous models were employed. For convenience of mesh generation, unstructured meshes were used in the propeller region of a ship, where the hull shape is formed of delicate curved surfaces. On the other hand, structured meshes were generated for the remaining part of the hull and its domain, i.e., the region of relatively simple geometry. To facilitate the rotating propeller for propeller a moving reference frame motion type technique was adopted. The computational results were validated by comparing with the existing experimental data. In this work we are interested in predicting the frictional resistance offered to a ship during is motion. To this effect we start off with a consideration of the resistance offered to the bare hull in the absence of the propeller and later extend to the case where the propeller is in-place. The thrust generated by the propeller alone without considering the ship (called open water analysis) is also performed using CFD. FLUENT 6.0®, was used for CFD analysis and for modeling and meshing the packages used are CATIA -V5® and ICEM-CFD® respectively. The open water analysis of the 4-bladed propeller predicted a thrust of 346 kN at 30 rps. The bare hull resistance at 228 kN at 18 m/s, and resistance with propeller in place at 18 m/s was found to be 245 kN. The results predicted by the CFD analysis were found to be suitable for the present HSDS and it is believed that the hydrodynamics design of the propeller is acceptable for the problem at hand. KeywordsResistance performance, propeller and shiphull interaction; Propeller open water performance; Mesh sequencing and converging study; Computational fluid dynamics.

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The present study focuses on the Preparation of Aluminum Oxide, and Copper oxide antifouling coatings to prevent or reduce corrosion and fouling in ships and marine vehicles. Al2O3 and CuO nanoparticles were prepared using the ball milling process. The nano paints were prepared using these nanoparticles as pigment and linseed alkyd resin as a binder. Mild-steel specimens coated with nano paint were immersed in seawater for 120 days and the properties were studied using Scanning electron microscopy and SEM – EDAX, X-ray Diffraction, and Fourier transform-infra red spectroscopy. It found an improvement in anti-fouling exhibited by Al2O3 mild steel plates and also an improvement using CuO when compared to bare paint. Contact angle measurement showed a marked increase for base paint which indicates its hydrophobic nature.