Submarine Design

[karabacak]

Hello,

I am wrting this mail from Turkey. We are the last year students of Istanbul Technical University Naval Architecture and Ocean Engineering Department. We are thinking about design a submersible for a competition that organised The Chamber of Turkish Naval Architects & Marine Engineers. We need proffesional help about our project especially for submerged devices stabilty. Can you help us about this way?


Best Regards,

Huseyin KARABACAK
Tel: +905069188312
huseyinkarabacak@hotmail.co.uk [/FONT]

[apex1]

Are you sure Huseyin you want a Multihull submarine?




Nothing amazes me in Turkey................

[karabacak]

I thing I wanna design mono hull I think I wanna a submerged plane

[hoytedow]

Put one hull inside the other, then you have a place for ballast tanks.

[Gannet]

We are thinking about design a submersible for a competition that organised The Chamber of Turkish Naval Architects & Marine Engineers.

Search the internet could not find anything on this competition

What are the rules for this competition, intended application(s) or mission statement for this submersible?

[Submarine Tom]

"especially for submerged devices stabilty"

Intrinsic (inherent) stability, dive planes and hydrodynamic design should provide you with submerged stability.

I'd be more concerned with surface instability, as this is where problems more often occur.

Tom

[karabacak]

Gannet, http://www.gmo.org.tr/

[Gannet]

I checked out the link, I am sorry I only know English.

http://www.uscg.mil/hq/cg5/NVIC/pdf/1993/n5-93.pdf

Enclosure 2 of the above discuss stabilty of a submersible both on the surface and submerged.

[ThomD]

I always thought a sailing trimaran sub would be cool. Amas on the surface, and the sub part would be foil shaped and submersed in the main hull position. Probably require the central section to be mostly flooded, still the idea would be to have the combination of sailing and underwater situation in one craft.

[Submarine Tom]

ThomD

There are plans out there for such a rig. Have a look on the Internet.

Let me know if you can't find it and I can help.

Tom

[DarthCluin]

Do you mean something like this:
http://www.rqriley.com/aquasub.html

[Submarine Tom]

That's the one!

Good going Darth.

I know a local guy who started building this but quit almost half way in.

Tom

[Submarine Tom]

karabacak,

Give us a little more to work with here.

Power source? Size? Safety requirements? Buoyancy? Control surfaces?

Earthquake resistance?

Stability's the easy part...

What have you got so far?

Tom

[karabacak]

Submarine Tom
Ma aim is designigning a submerged plane.
I wanna use just dynamic dive for going deep
I thing I wanna use gas trıbunes and being as fast as possible than going underwater.
and th emain thing about this project I wanna develop my self on submarines...

[Submarine Tom]

karabacak,

Okay, well we have a similar dream.

So does this guy, check out his web-site.

He has lots of money!

He hopes for 25 knots but I can't see how he's going to get more than 15!

http://www.psubs.org/projects/123768...00submersible/

Cheers, Tom

[zeroname]

links not working

[Submarine Tom]

Sorry about that, this should fly:

http://www.psubs.org/projects/1237684922/r300submersible/

Tom

[karabacak]

the link do not work tom unfortunately

[Submarine Tom]

I just tried it and it worked...

[bntii]

Wow- Remarkable effort and result in that sub.

http://www.psubs.org/projects/1237684922/r300submersible/photos/large/LiftsupportTest7-AutomaticSystemCheck-9hours,Chris003.jpg

[Submarine Tom]

Yes, no expense spared. He is semi-retired but busy as hell.

He still has only two or three sea-trials under his belt.

I look forward to further test results.

Tom

[bntii]

Tom- do you know if this is being put together as a prototype for a production boat or a one off?
The page on psubs is great on photos but a little lite on back story. I would like to know a bit more about the build.

[Submarine Tom]

bntii,

Both. Cliff is a pretty private guy and he doesn't/didn't want a lot of

publicity with his build. He is a "retired" fluid dynamics engineer with his

own company. He built it as a one-off but to spec for production and

commercial sale should he decide to go that way. It's fly-by-wire, 10kw,

touch screen. I recall about 3-tonnes submerged. We corresponded

for some time by email but I haven't heard from him for months now...

He's got 20 degree all-round articulation on the jet nozzle and I assume

the "ailerons" function as pitch and roll control surfaces via the fly-by-wire

computer. Pretty well my dream machine if I had the $$$.

There are a few things I would do differently, but not much.

Tom

[bntii]

Thanks

[tspeer]

...We are thinking about design a submersible for a competition that organised The Chamber of Turkish Naval Architects & Marine Engineers. We need proffesional help about our project especially for submerged devices stabilty. Can you help us about this way?

To the best of my knowledge, there has only been one successful flying submarine - the Reid RFS-1.
http://www.1000aircraftphotos.com/Contributions/KleinBernhard/6559L.jpg
This was basically a submersible airplane. The air propeller had to be removed and the engine sealed before it could submerge. The cockpit was completely flooded, so this was a wet sub. But it did both submerge and fly.

What are the requirements for your craft? I suggest stability when submerged is the least of your problems. If you have a configuration that is stable in the air, making it stable underwater should be straightforward. I think you should focus on more fundamental issues, such as performance, both airborne and submerged.

If you think through the issue of a flying sub, I believe you will realize that any air space when submerged is a huge problem if the craft has to fly, because the weight needed to overcome the buoyancy of the air space has to be lifted when the craft flies. Fuel becomes a problem both submerged and flying, because fuel is lighter than water and any buoyancy is detriment to being able to submerge.

Treat this as an airplane that can submerge rather than as a submarine that can fly. That was Reid's approach, and I think it's the only practical one. I suggest you don't try to submerge using negative buoyancy, but fly the craft down using negative lift and positive buoyancy. I also suggest you do not try to make a dry sub, but flood every void within it - including the fuel tanks (use bladders to separate the fuel from the water).

[Submarine Tom]

tspeer,

I don't believe anyone said anything about flying in the air, rather flying in

the water, unlike a conventional submarine.

Interesting photo you posted though.

[oralpiskin]

hi,
is it reasonable to use ITTC 1957 method to calculate the resistance of a submerged vehicle?

[DarthCluin]

I think what KARABACAK is designing is a heavier than water craft. He doesn't expect it to fly in air, he wants it to fly in water.
I think I read about them in a novel, possibly by Martin Caidin, or Lee Corey (G. Harry Stine's pen name).
Submarines as we currently know them are the aquatic equivalent of ballons, blimps, and dirigibles. A heavier than water craft would use hydrofoils to generate lift while in motion and water jets to hover.
The main advantage is that if you don't have to float, you can build heavy, to go deeper, put bigger motors in to go faster, or just build smaller.
The main disadvantage is if you lose power, you sink.
I don't know if anyone has tried to build one before, and if they did, I hope they tested it someplace shallow.

[Gannet]

...A heavier than water craft would use hydrofoils to generate lift while in motion and water jets to hover.
The main advantage is that if you don't have to float, you can build heavy, to go deeper, put bigger motors in to go faster, or just build smaller.
The main disadvantage is if you lose power, you sink.
I don't know if anyone has tried to build one before, and if they did, I hope they tested it someplace shallow.

Graham Hawkes' Sumersibles always have positive buoyancy and uses negative hydrodynamic lift to keep the submersible down so that if it losses power or propulsion it would always rise to the surface. See attachments

Enjoy
Gannet

[DarthCluin]

As a firm believer in Murphy's Law, I would feel a lot safer in the Hawkes boat, however, it is still a dirigible.
Mind you I like dirigibles. I think the best one in the water was the U.S.S. Albacore AGSS569 (though in the air I have other preferences:D ).

[Submarine Tom]

Neutral buoyancy is the way to go here.

My design is -1 kg on launch, +2 kg on recovery.

Flight time one hour.

Call it neutraly buoyant, which only makes sense.

Why waste power creating lift (positive or negative) when you don't need to.

[karabacak]

ma ack what do you thing or using gas turbines @ submarines when it sailing
do you thing that can give admiring speed to submarine