Kayak and Canoe Design Bulletin Board

Re: Effects of width/heigth scaling on hull qualit

Posted By: Nick Schade
Date: Tuesday, 6 July 1999, at 9:11 a.m.

In Response To: Effects of width/heigth scaling on hull qualities (Jan Gunnar Moe)

Assuming you keep the boat on the same waterline, the simple scaling you mention should not change the hull form coefficients at all. The only thing it should change is the volume and the various areas. Things like the prismatic will not change. Just reducing the wetted surface area should improve the efficiency.

> Let us assume that you scale the forms by 0.9, so that volume will be
> scaled by 0.81. Remember length stays unchanged, as you do want a sleeker,
> narrower kayak.

> Question:

> Will this procedure destroy the value of the hydrodynamical optimization
> made by John Winter for the original design? I understand very well that
> the "new" design will not be optimized for the same speed as the
> original. But will it be optimal or sensible for some higher speed? Or
> will it simply be a "not so good as it should be" design when it
> comes to how it will work in the water? That is: Should other changes have
> been made if performing such a scaling in two dimensions, should a
> completely new optimization using Kaper and Michelet and... have been
> done?

> Or is this the kind of individual tailoring which one may do without
> worrying about beeing not so smart?

> Jan Gunnar Moe

Messages In This Thread

Effects of width/heigth scaling on hull qualities
Jan Gunnar Moe -- Tuesday, 6 July 1999, at 7:11 a.m.

Re: Effects of width/heigth scaling on hull qualit
Nick Schade -- Tuesday, 6 July 1999, at 9:11 a.m.

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