Delft series

[willfox]

I am currently workng on a delft series excel program. I am using the regression coefficients which were based on pre 1992 yachts as i am designing a heavier displacement classic cruiser. Im not too sure if I have got the correct equation.

has anyone got a link to this equation. I seem to be getting silly figures such as 1500kN at a Fn of 0.35 for a 13 m lwl and 20 odd tonne yacht?!! :confused:

[terhohalme]

The residual resistance number is more or less on the spot but not kN, just N. Don't forget viscouse resistance.

Terho

[Ad Hoc]

can you post the output?

[Alik]

I always use 2-4 methods for resistance prediction (of course, proper methods with matching parameters). Never trust only one method to predict the resistance...

For heavy displacement boat - try trawlers/tugs series. Delft series is known to underevaluate resistance of heavy motorsailers, while formally parameters of series match.

[Alik]

This is sample for 16m trawler-style boat powerboat, calculated by same software.

Need to say that formally boat fits in parameters of Delft series, but resistance is very different due to variations of hull shape.

[willfox]

Im not too sure how i would attach the spreadsheet unless i could get email numbers?