Design Ratios, British And Metric Units

[marshmat]

I think that's what a lot of us do, Basil.

I always work with the true dimensionless ratios for design, but all my spreadsheets that use them have a few lines to convert them to the traditional form, just in case someone wants to compare them.

[BASIL J WALL]

Thanks Matt...
I will now modify my spread sheets...
Basil

[rxcomposite]

Thanks for the explanation Matt. In my design work, I use the S.I. system the modern method of the metric, to be on the mainstream. But in my work as a surveyor, I still encounter a lot of ships with the U.S. English system and our reporting requires us to report the fuel in the Imperial system because the country I work for has adopted the British system. You will also be surprised that the word ton is so frequently used without reference to M.T., S.T., or L.T. Makes me think the world has not changed after all.

Its nice to know there are other ways of expressing DLR ratio as the Principles of Naval Architecture stiil list the design lane in DLR ratio. Have to "modernize" my spreadsheet so I can work purely on dimensionless ratio.

[rxcomposite]

Originally Posted by marshmat

-S-number, which takes the old-style DLR as one of its inputs.

What does the S stands for. Or what does S/Sqrt(displ x L) stands for?

[DCockey]

Originally Posted by rxcomposite

What does the S stands for. Or what does S/Sqrt(displ x L) stands for?

Essentially a performance rating number for monohull sailboats which can be calculated from generally available information. Eric Sponberg included it in his "The Design Ratios" article: http://www.sponbergyachtdesign.com/Articles.htm