Talk:Froude number
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Hi
I reckon this page might be better split into two: Froude number and a separate page for densimetric Froude number. Comments?
(William M. Connolley 09:31, 2004 Mar 16 (UTC)) Its a fairly short page now and if split would be very short. It might be better to expand it first. Unless you want to create links into it. But if you feel strongly, go ahead.
[edit] Fr and Ri are interchanged here
The definitions of Froude number and Richardson number are interchanged. Should I edit it or suggest that the author should do so? I'm not sure of the protocal. --Dankelley 01:04, 19 Jul 2004 (UTC)
Hi Dankelly.
The usual protocol would be for you to edit the article, if you are sure of your position. However, in this case, it would be better to do one of the following:
- leave the articles unchanged because the definitions are generally accepted
- say something like "Some workers (such as X and Y) follow the notation used in books Y and Z, and seminal articles A and B, and use a different set of definitions, viz: . . .
I'd do the second option myself If I'd ever seen Fr and Ri defined the other way round!
Best wishes
Robinh 08:16, 19 Jul 2004 (UTC)
- (William M. Connolley 21:16, 24 Jul 2004 (UTC)) The defs look OK to me (in the sense that they match googling, eg: http://scienceworld.wolfram.com/physics/RichardsonNumber.html or http://www.gfdl.noaa.gov/~smg/MOM/web/guide_parent/s7node262.html
- And just to be sure I've looked it up in Gill who agrees F = U / N_1.H
William Froude takes credit for the Froude number which bears his name. It was originally defined by Froude in his 'Law of Comparison' in 1868 in dimensional terms as Speed-Length ratio
Speed-Length Ratio = V / ( L )^0.5
where:
- v = speed in knots
- L = LWL in feet
The Naval Constructor Reech put forward the concept in 1832 but had not demonstrated how it could be applied to practical problems in ship resistance.
Fn was later refined to the non-dimensional :
Fn = v / ( g L )^0.5
where:
- v = speed in m/s
- g = gravity in m/s2
- L = LWL in m
It should be defined as such.
Ref: Principles of Naval Architecture (SNAME), 1988, Vol II, Page 5.
Jmvolc 00:42, 19 May 2006 (UTC)
[edit] Length and Depth Froude numbers
This document explains Length and Depth Froude numbers, and appears relevant to development of the article.
http://www.qub.ac.uk/waves/fastferry/reference/MCA457.pdf
I have added an external link to it from the article. GilesW 13:26, 25 June 2007 (UTC)
