In article ,
Stephen Baker wrote:

"THe energy associated with the transverse wave system travels at the "group
velocity" of the waves, which equals one-half of the phase velocity in deep
water. The propulsion system of the ship must therefore put additional energy
into the wave syste, to replace that which "falls behind". A nominal
relationship between ship speed and the length of the corresponding transverse
wave may be found by equating the ship velocity with the _celerity_ (phase
velocity) of a small-amplitude gravity wave in deep water,

Vship = Cwave = sqrt( g.Lw/(2.pi)) = 2.26 sqrt(Lw)

Yes, this is the formula. But what I'm interested in is the theory
it's based on - the general theory of waves in fluids, of which
small-amplitude deep-water surface waves are one particular case.



Thank you,
Sakari Aaltonen

Sakari says:

Yes, this is the formula. But what I'm interested in is the theory
it's based on - the general theory of waves in fluids, of which
small-amplitude deep-water surface waves are one particular case.


What you need is not a discussion on the hull-speed theory, but a degree in
fluid dynamics.

;-)

Seriously, however, this is what you need to read, although you may need more
background first.

http://www.amazon.com/exec/obidos/tg...=1058555603/sr
=1-6/ref=sr_1_6/002-5456679-7453635?v=glance&s=books

Steve "application not theory" Baker

Stephen C. Baker - Yacht Designer
http://members.aol.com/SailDesign/pr...cbweb/home.htm

In article ,
Stephen Baker wrote:

Seriously, however, this is what you need to read, although you may need more
background first.

http://www.amazon.com/exec/obidos/tg...=1058555603/sr
=1-6/ref=sr_1_6/002-5456679-7453635?v=glance&s=books

Lighthill, James: "Waves in fluids"? Yes, our library has several
copies. However, I happened to pick up "Mathematical theory of wave
motion" by G.R. Baldock and T. Bridgeman; it might be just enough.

But I'm leaving for a three-week sailing vacation on Sunday, and
shall, for some time, be concentrating on real waves instead of
theoretical ones.


Sakari Aaltonen