New propulsion sytems for ships

[kach22i]

Originally Posted by asfekar

hi. are there anybody who experienced zodiac rib's overall propulsion efficiency. i will build my first craft. i will use %55 overall efficiency in hydromax. and then i will add %15 machine +sea+propeller margine.
is it true.

There might be a better location than in this thread. I'm thinking there is a large surface wetted area with some parasitic drag with it. My current hovercraft skirt has a lot of pressure in it (too much and similar to an inflatable) and looks someting like a Zodiac, the instant and huge amount of drag I encountered when I tried a banking turn caught me off guard and I came off cushion. I would think an RIB would have similar issues because of it's wide bow.

Keep it planing in a straight line and I think you will be fine, just be careful of tight turns, they will slow you right down.

[kach22i]

Originally Posted by charmc

Right, Matt. The age old question: How much energy does it take to make this energy useful?

I like it, though, out of the box thinking. And as George noted, it would be really cool to zap the ocean around an attacking warship and set it on fire.

Didn't some ancient Greek do something similar with polished shields?

[kach22i]

Not to get off topic, but I just took a visit to the DeJong and Lebet website, and I saw something which caught my eye.

Click link to see full sized image............
http://www.dejongandlebet.com/949_SeaFair.htm


http://s184.photobucket.com/albums/x295/kach22i/


What's the story on these propellers?

Are these the whale flipper ones out of Canada in use already?

[Guillermo]

'Grand Luxe' seems to be a fancy looking canals boat, possible very difficult to handle when in strong winds. Propulsion system is not the extraordinary thing, from my point of view, but the very, very low draught.

[brian eiland]

Basically just Kort nozzels....tugs have used them for years

[charmc]

Originally Posted by Guillermo

'Grand Luxe' seems to be a fancy looking canals boat, possible very difficult to handle when in strong winds. Propulsion system is not the extraordinary thing, from my point of view, but the very, very low draught.

You're right about the shallow draft, but "canal boat" is pretty much the intended use. The boat is unique, a floating art gallery and upscale shopping boutique for a limited number of very wealthy people. It's designed for navigating in protected waters only, much like a dinner cruiser. One reason the draft can be so shallow is that almost all usable space is open exhibit space, with little onboard storage. Supplies and staff are on a support boat which follows along. http://www.allbusiness.com/north-ame...1023842-1.html

I wanted to view some art, but I did not get an invitation, as I am not mega-wealthy (I knew that already).

[kach22i]

Originally Posted by brian eiland

Basically just Kort nozzels....tugs have used them for years

...........and the ripples or ridges on the prop blades?

[Pericles]

Machining! Nought else.

Pericles

[charmc]

Originally Posted by kach22i

...........and the ripples or ridges on the prop blades?

Different thread, same answer, George. They are grinding/buffing marks; the surface of the prob blades is smooth.

[kach22i]

Originally Posted by Pericles

Machining! Nought else.

Pericles

Example of burnishing finish:
http://www.olds.com.au/marine/


I'm 50/50 on this, here is a picture of a hovercraft fan coming to the marketplace soon.

http://www.hoverclubofamerica.org/fo...showtopic=1232

[Guillermo]

Originally Posted by kach22i

I'm 50/50 on this, here is a picture of a hovercraft fan coming to the marketplace soon.

Humpback whales fins theory in action!

George, I humbly suggest you not to post such big images within the corps of the message, as they make all posts in the thread to come out of computer screen's borders. Very uncomfortable to read. Thanks in advance.

[kach22i]

Originally Posted by Guillermo

George, I humbly suggest you not to post such big images within the corps of the message, as they make all posts in the thread to come out of computer screen's borders. Very uncomfortable to read. Thanks in advance.

Every forum site reacts differently, oops on my part.

http://www.loremo.com/forum/board_en...SID=eec8554527
http://www.freepistonpower.com/fp3.htm

FP3 design is based on "free pistons" being driven back and forth inside cylinders by controlled internal combustion. Permanent magnets are attached to the pistons. As the magnets move, electric power is generated in coils placed around the magnets.

[charmc]

"German wind power leader Enercon GmbH is applying wind power to an "E ship" it has ordered from Lindenau-Werft, Papenburg, Germany, for delivery next year. The 130 m long LO/LO will be powered by a diesel-electric power plant and four 27 m high by 4 m diameter Flettner Rotors."

http://www.nxtbook.com/nxtbooks/sb/ml0507/

[charmc]

"Could nuclear power ever make sense for any ship other than an aircraft carrier, a submarine, or an icebreaker? The cynical answer is, 'Not if we shopped where the Navy shops.'

But a new generation atomic engine need not be the type of plant used in aircraft carriers. For years now, Rod Adams of Adams Atominc Engines has been proposing what he says is 'a reasonable and practical way to produce nuclear engines with power outputs of between 1 and 100 MWe.' The engines would be closed cycle gas turbines using nitrogen heated in a graphite-moderated nuclear reactor. ... The plan is to use series production techniques and the economy of unit volume instead of the economy of scale as the basis for allowing nuclear power to compete successfully with other fuel alternatives."

http://www.nxtbook.com/nxtbooks/sb/ml0507/

http://www.atomicengines.com/ships.html

[Guillermo]

Thanks, Charlie.