In article ,
D MacPherson wrote:
sci.engr.marine.hydrodynamics - but this is not very active.

However, you might find what you need by doing a Google search in the
"Groups" section for "hull speed". There was a large tread about hull speed
in rec.boats.builder a couple years back. You'll find more opinions than you
ever wanted...

Thanks, but I'm not looking for _opinions_, really. I went to the
library today and found quite a number of books on fluid dynamics.
Some had sections on surface waves; the mathematical derivation
shows, indeed, that the propagation speed of such a wave is directly
proportional to the square root of the wavelength. I'll need some
time to work through that derivation...:-)


Sakari Aaltonen

Sakari Aaltonen ) writes:

Thanks, but I'm not looking for _opinions_, really. I went to the
library today and found quite a number of books on fluid dynamics.
Some had sections on surface waves; the mathematical derivation
shows, indeed, that the propagation speed of such a wave is directly
proportional to the square root of the wavelength. I'll need some
time to work through that derivation...:-)

well, you start with V = N x L where V = wave velocity, N = frequency of
vibration, and L = length of wave. that dosn't give you the square root of
wavelength, but something about the boat sitting down into the wave trough
gives an equation with boat length (water line length) as a factor but
darned if I remember how. I've seen it in one or two library books but
never wrote it down.

you'll have to post the derivation so its preserved in the newsgroup
archives for all time.

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How about the Pierre Gutelle book?
I have it in french but it is available in english, Wooden Boat sells it.
I found all the math theory about wave resistance with formulas in the 2nd
chapter then, it is applied in chapter 5.
He also shows a good bibliography listing many papers and books about wave
resistance.
Gutelle may give you all the answers you are looking for.
You'll see why that hull speed formula is very crude.
The French title is "Architecture du Voilier", volume 1 of 3.

--
Jacques
http://www.bateau.com

"Sakari Aaltonen" wrote in message
...
In article ,
D MacPherson wrote:
sci.engr.marine.hydrodynamics - but this is not very active.

However, you might find what you need by doing a Google search in the
"Groups" section for "hull speed". There was a large tread about hull
speed
in rec.boats.builder a couple years back. You'll find more opinions than
you
ever wanted...

Thanks, but I'm not looking for _opinions_, really. I went to the
library today and found quite a number of books on fluid dynamics.
Some had sections on surface waves; the mathematical derivation
shows, indeed, that the propagation speed of such a wave is directly
proportional to the square root of the wavelength. I'll need some
time to work through that derivation...:-)


Sakari Aaltonen

In article ,
Jacques Mertens wrote:
How about the Pierre Gutelle book?
I have it in french but it is available in english, Wooden Boat sells it.
I found all the math theory about wave resistance with formulas in the 2nd
chapter then, it is applied in chapter 5.
He also shows a good bibliography listing many papers and books about wave
resistance.
Gutelle may give you all the answers you are looking for.

Thanks, but I think anyone writing on boats is more interested in
applying the theory (of fluid dynamics) than explaining or, indeed,
deriving it.

I'm quite prepared to read a textbook on the subject. It's not
_quantum_ physics...


Sakari Aaltonen

Don't misjudge that book, you clearly have not seen it.
It shows around 50 pages of formulas and graphs just about your question and
Pierre Gutelle is not shy about using math. It is not a vulgarization book.
You need to be fluent in integral calculus to understand those chapters.

--
Jacques
http://www.bateau.com

"Sakari Aaltonen" wrote in message
...
In article ,
Jacques Mertens wrote:
How about the Pierre Gutelle book?
I have it in french but it is available in english, Wooden Boat sells it.
I found all the math theory about wave resistance with formulas in the
2nd
chapter then, it is applied in chapter 5.
He also shows a good bibliography listing many papers and books about
wave
resistance.
Gutelle may give you all the answers you are looking for.

Thanks, but I think anyone writing on boats is more interested in
applying the theory (of fluid dynamics) than explaining or, indeed,
deriving it.

I'm quite prepared to read a textbook on the subject. It's not
_quantum_ physics...


Sakari Aaltonen