On Sun, 15 Oct 2017 19:12:02 -0700 (PDT),
wrote:

On Monday, March 4, 2002 at 5:43:46 PM UTC-5, Dan Bollinger wrote:
The 455' long steamboat the 'Commonwealth' was fitted with compound engines
and feathering wheels instead of a propeller powered by steam turbines.
Operating costs were estimated to be identical. They noted that the reduced
space and vibration of a paddlewheel made the deciding factor. Its top
speed was 23 mph in the trial run. Dan


"Glenn Ashmore" wrote in message
...
Just thinking about the physics, aside from the wheels and drive
mechanism being a lot heavier, I would suspect that paddle wheels will
waste a lot of energy producing a lot more side eddies than a prop will
and as the speed increases it will start throwing more water up than back.

As for Junkyard wars, the only thing the paddle wheel has going for it
is less draft. As it is highly unlikely that they will convence the
owner of that antique tripple compound that siezed up for lack of oil
last year to lend it out again, they will probably seed the yard with a
couple of gas engines so I would go with a prop unless the contest is in
water only a few inches deep. But then one of the teams will probably
luck into a discarded Arneson surface drive. ;-)

wrote:

I'd like to know if anyone has references to theoretical comparisions.
I've alway thought a paddlewheel could be more efficient than a prop.
I assumed they went out of style because they were large and bulky and
fuel was cheap. I think there could also be problems with wave,
suface interactions, and I can't see it working well for a high speed
planing hull.
-



--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com



Dan, Where did you find this information? Im curious on the subject.

I assume that this was the sidewheeler STEAMER COMMONWEALTH, delivered
to the owners in 1908.

Try googleing on 'THE STEAMER COMMONWEALTH' (without the quotation
marks of course) there is a very informative PDF copy about the boat,
with the above title, of a paper Read at the sixteenth general meeting
of the Society of Naval Architects and Marine Engineers, held
New York, November 19 and 20, 1908.

--
Cheers,

John B.

Does anyone think that perhaps a propellor is more efficient because it's blades are moving through the water in a way similar to the wings of an aircraft at an efficient angle of attack, whereas paddle wheels have no laminar flow, like a plane in a stall or a boat with the sails close hauled when on a reach?