How to predict the ship power

Hello all , I want to predict the power of a ship (85m), and I haven t a model to predict the resistance and specialy the wave making resistance . is it possible to predict the power using maxsurf? i have a version of Maxsurf but without the workshop, is it possible to import from autocad?or only the control points will be exported ?
best regards

[Eric Sponberg]

Generally, you don't need a surface model or other 3-D model to predict horsepower and speed. The most sophisticated program that I know of, and which I have, is NavCad, from Hydrocomp Inc. in Durham, NC. You need only the major parameters for the ship (length, beam, draft, displacement, etc.) and the type of hull (displacement, semi-displacement, planing, sailboat, etc.) to calculate an estimated speed and power. It will also calculate the required propeller diameter and pitch if you know which engine you would like to use.

Eric

[lovel Jelacic]

Hi Aziz,
There are lots of power prediction algorithms, but catch is that most of them are specialized for some type of ships. Generaly, for larger ships not considering the type the best algorithm is one developed by Holtrop & Mennen, based on hundreds of basin experiments. The complete paper on Holtrop-Mennen method you can download on my site: http://www.geocities.com/brodograditelj
Go under "Study topics" and download holtrop.pdf, it's in english. I had incorporated the calculations from that paper into an excel spreadsheet, but... it's in Croatian. Maybe you can find some english versions on the net...