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" <[email protected]> wrote in message news:[email protected]...

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. ;-)

[email protected] 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.

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On Sun, 15 Oct 2017 19:12:02 -0700 (PDT), [email protected]
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" <[email protected]> wrote in message
news:[email protected]...

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. ;-)

[email protected] 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.

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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?

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I've read that ships at sea, because of wave action, tend to rock from side to side, causing the paddles to lose contact with the water, sometimes 50% of the time greatly affecting the efficiency. Screw props are always in full contact with the water.
In my opinion, the main reason paddlewheels fell out of favor is that the mechanisms are more complex and most importantly, take up a lot of space.

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On Fri, 5 Jun 2020 13:27:23 -0700 (PDT), [email protected] wrote:

I've read that ships at sea, because of wave action, tend to rock from side to side, causing the paddles to lose contact with the water, sometimes 50% of the time greatly affecting the efficiency. Screw props are always in full contact with the water.

In my opinion, the main reason paddlewheels fell out of favor is that the mechanisms are more complex and most importantly, take up a lot of space.

I believe that there are still Paddle Wheel vessels operating. See https://en.wikipedia.org/wiki/Paddle_steamer
--
cheers,

John B.

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