Pulsed Outboard Motor?

[Hank]

Hello- I see some basic conflicts in this idea with the way things work. There is a viscosity discrepancy, as well as a specific gravity one, that would preclude this idea from being turned into something useful. A tuned duct could not be constructed that would give the desired effect, controlled sustained motion.
If I were considering Pulsed Combustion as a prime mover in a maritime enviornment I'd use the heat generated to boil Mercury and impel a turbine with it. The exaust efflux would also provide some impulse in the form of thrust. The noise of it all would scare the fish and be a magnet for sonic guided munitions. Hank

[yipster]

Hi and lol, aint no scientist but really like(d) the thought!
i'm learning and think i'll like to do some small (handle with care) poppop expiriments...

found some related links
jet sim: http://www.grc.nasa.gov/WWW/K-12/airplane/ngnsim.html
moving fluids: http://www.grc.nasa.gov/WWW/K-12/airplane/bern.html
steam propulsion: http://www.pursuitdynamics.com/Marine.asp
physics: http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html
and some pulse toyboat designs at http://www.knatter-tom.de/geschichte.html

here may be one to boil for mercury: http://www.angelfire.com/ak/egel/coanda.html

[sparks]

Bruno, do you have any ideas where i could find more about the McCOLLUM monster?
My websearches have been fruitless.
Did it ever get out on the market.
If it was just a "brainfart", it sure was a most beatiful one!

[Bruno Ogorelec]

Bruno, do you have any ideas where i could find more about the McCOLLUM monster?

No, I'm afraid I have no other document mentioning the thing but what I published here. My late father told me once that a similar engine was tested by Germans shortly after WW 2 but he could not tell me the source of the story and I never found confirmation.

[sparks]

Actually not entirely fruitless.
The pat. appl. number on the picture did lead to som documents in one of the searchable patent archives (cant remember the url, but i may still have it somewhere) .
Unfortunately they were in some special-TIFF format requiring a viewer that for some reason didn't install properly on my computer.

[Bruno Ogorelec]

Unfortunately they were in some special-TIFF format requiring a viewer that for some reason didn't install properly on my computer.

Try again. I did it two or three times on different computers and it worked fine. It will unlock a treasure trove of patent applicaton documents.

[Mark]

[quote="yipster"]Hi and lol, aint no scientist but really like(d) the thought!
i'm learning and think i'll like to do some small (handle with care) poppop expiriments...

I ain't no genius, but I really liked the links you listed. The little putt-putt boat designs were a good way to see how far a "simple" idea can interest creative minds. I like the glass tubing coils as a variation and the imaginative artwork in the little boats.
Then too the "steam engines" were just as interesting. I once saw a steam injection water pulse engine in a recent science magazine where a blizzard of collapsing bubbles of steam created a tremendous impulse underwater. Why I have even read some scientists speculate that collapsing bubbles from sonic energy might be enough to create fusion!

http://www.spacedaily.com/news/energy-tech-04o.html

Imagine a simple putt-putt boat working on the same principle as fusion. As of yet of course collapsing bubbles haven't been proven to produce fusion but they have created strong propulsive devices.
Air and water can energetically fill a void.
Mark

[haaken]

Moving water is FAR more effective then moving air right, therefore I propose that if one was to put the exhaust underwater it would create a seriously powerful outboard motor.

By pushing against water there will be far more pressure in the chamber, so you would need strong valves (slow), but this is helped by using exhaust valves preventing backflow ... therefore the vacuum can only be filled by the intake air. A blast reflector helps shoot back some exhaust for a sustained pulse.

Think its workable? or is this just another idea thats been posted before........ :(

I think it is possible, take a look at the attachment. Notify the unusual lenght of the ram air intake.

[Mark]

Interesting the position of the tip of the exhaust pipe to the level of the water, the exhaust is half in and half out of the water, I wonder how critical that is?
Mark

[Mark]

That was a nice find Haaken, are there any more pages that you have on that water pulsejet, some written discriptions of characteristics?
Thanks,
Mark

[larry cottrill]

Interesting the position of the tip of the exhaust pipe to the level of the water, the exhaust is half in and half out of the water, I wonder how critical that is?
Mark

Mark -

That partial immersion will 'come and go' with the slightest roughness in the water, as well as the turbulence behind the boat. What's way more critical [and innovative] about that design is using water as a thrust augmentor. That's wonderful, and could be used to a limited extent in a flight engine, as I have suggested on several occasions before.

Here's an idea that occurred to me when I saw the Calcium Hydride chemical on Ebay you posted the other day:

Make a hydrogen generator such that it has a port for hydrogen gas at the top and a relatively tiny port for water ejection at the bottom. When the hydride goes in, the hydrogen pressure in the generator forces gas rapidly out the top, where it's used to fuel your pulsejet. A tube from the water runs to a liquid-spray augmentor at the tail of the engine, where its mass contributes to thrust as it gets sprayed in and expanded in the diffuser part of the augmentor.

The only obvious flaw in this plan is that what you're spraying out the back of the jet is calcium hydroxide, something roughly similar to lye solution! You might want your launcher dressed in protective gear.

L Cottrill

[Mark]

If you were naming the little calcium hydride motor, a good name would be the "Lime-o'-dyne". Might make for a good toy boat size. You'd go broke scaling up.
I wonder how submerger the tail could be and still run, too bad it's not completely underwater from a sound point of view.
Mark

[yipster]

Mark, Haaken, Larry i'm fascinated by your ideas and came across mentioned article of the Pursuit steam jet at http://www.newscientist.com/news/news.jsp?id=ns99993321 that states "a version just 20 centimetres long developed around 30 horsepower (22 kilowatts) in a test tank" i hope food for more thoughts before they turn the OB into a fire extinguisher? http://www.newscientist.com/news/news.jsp?id=ns99994738

[Mark]

That's the one I read about in Popular Science a few months ago, it's interesting stuff, kind of like the little putt-putt toy steam boats in some remote related way. Looks like the name of the game is surface area, getting lots of tiny bubbles to condense suddenly building feedback. I only am recalling what I vaguely remember about it. I'm no expert in bubble boating technology.
It's nice to review this subject, I wonder if hot little air pockets could be suddenly cooled and work like the steam boats somehow? Just dreaming, maybe you could emit hot air through air stones with a lot of surface area or something, chilling the air.
Mark

[Mark]

I was just looking at a Newcomen Atmospheric Engine, kind of the same as a putt-putt boat in some respects, steam drives a piston and then a jet of cold water is misted into the cylinder collapsing the vapor pressure.
Mark