[PSUBS-MAILIST] Re: Big motor for PSUBS...ATTN: K. MARTINDALE...

["Michael B. Holt" <mholt@richmond.edu>]

Captain Nemo wrote:
> I can compute things like weight and balance, volume and displacement, and
> hydrostatic center of gravity; but when it comes to mathematically
> calculating a motor's performance in a given hull design, I'll admit I aint
> the sharpest tool in the shed.  I just look for as much thrust as I can get,
> and figure I can always drive slower; and  so far (for the size and type of
> subs I build) that's been good enough.  But I can see where more precise
> information could be desirable.

I'm have the formula from Busby (page 397) in a working Visial Basic 
program.  If you want it I'll email the EXE to you.  It will duplicate
what Busby says in his book, but beyond that I offer no guarentees. 
(It did tell me that the Nautilus in the book would need 4400 HP to
move at 15 knots.)

I'm working through a table-load of books about ship design, trying
to use the classic formulae to determine horsepower.  So far I've
tried four appraoches, on a spreadsheet, and the accuracy is not
good.  I have two more formulae to test.  More, as it happens.

> The first guy who comes to mind that might be able to answer your question
> is KEN MARTINDALE.  Whatayathink, Ken?

Ken, go for it.  I'll take all the expertise that's offered. 


Mike Holt