Super yatch design study for Malaysian sea (Langkawi Island)

Malaysia as a country surrounded by water has a huge economic and geographical potential in the development of super yacht industry in South East Asia. There is lack of super yacht design study specifying to Malaysian marinas and seas. Most of the super yacht operates in Malaysia were built and bought directly from oversea, and chartered by foreign companies. It is hence the purpose of this study to survey on Malaysian sea water, particularly Langkawi Island, to introduce a design methodology in producing a preliminary design of super yacht that suits Langkawi Island, and serves as a guideline for future super yacht design for Malaysian sea in different marinas. Suitable dimensions of super yacht were derived by using dimensional relationship via statistical method. Two types of hull form designs (round bilge and V-bottom hull) were designed using Maxsurf Pro software. Resistance analysis on the two hull forms were carried out using Savitsky Pre-Planing and Compton methods via MaxsurfHullspeed software, and stability performance of the two hull forms was analyze using Hydromax software. VBottom hull form is found to have better resistance performance as compared to round bilge hull form, and both hull forms are found to be in stable conditions and comply with IMO requirements

Review of micro-bubble ship resistance reduction methods and the mechanisms that affect the skin friction on drag reduction from 1999 to 2015

In order to lower down the fuel consumption and to achieve higher speed of ship, reduction in ship resistance has been the major topic of research for a long time. The most important factor in ship resistance is skin friction resistance. Micro-bubble has been shown to be able to reduce skin friction. This micro-bubble method gives the possibility to lower the friction without any change in the present hull form of a ship. The application of the micro-bubble technique reduces the surface friction by a variation of the viscosity of the fluid around the ship and makes a modification in the structure of the turbulent boundary layer. However, not much is known about the correct size, quantity, area of coverage which can effectively form a skin friction reducing mechanism. There are many established methods, such as Venturi tube type generator, tangential water-jet and forming of dissolve air and also a chemical process, such as electrolysis, may result in bubble production [1.. The use of micro-bubble as reducing agent of drag can lead to the creation of bubbly mixture near the flow surface that can significantly advances in the understanding of the underlying physical process of drag reduction. The current applications of these techniques to surface ships are discussed