Search found 67 matches

by vhautaka
Tue Jan 27, 2004 11:20 pm
Forum: Valveless pulsejet forum
Topic: Well, I almost got something to run... a Lockwood.
Replies: 5
Views: 3081

Oh yeah, could -10C weather and the engine lying in snow affect starting/running characteristics? The gas tank had been kept in the warm workshop prior to tests and we got lots of gas out, bot in gaseous and liquid mode, enough to sustain a big yellow flame at the tailpipe. But would the pressure st...
by vhautaka
Tue Jan 27, 2004 3:26 pm
Forum: Valveless pulsejet forum
Topic: Well, I almost got something to run... a Lockwood.
Replies: 5
Views: 3081

Well, I almost got something to run... a Lockwood.

Hello again people, last weekend I finally made it to the countryside with a friend of mine. We started out trying to put together a simple Lockwood, as I already had a bunch of printouts with the necessary dimensions for any engine size. The pipe-in-pipe designs I have in mind will still have to wa...
by vhautaka
Thu Jan 22, 2004 10:24 am
Forum: Valveless pulsejet forum
Topic: Liquid fuel tank pressurised with compressed air?
Replies: 2
Views: 1987

Okay... the squeezing of air in with that fuel is what I was not sure of / what seemed the most suspicious. I'm not worried about spraying, at least not any more than with propane. Any liquid gas is pretty dangerous in the way of freezing and peeling off human skin/eyes/whatever at the same time it ...
by vhautaka
Wed Jan 21, 2004 11:53 pm
Forum: Valveless pulsejet forum
Topic: Liquid fuel tank pressurised with compressed air?
Replies: 2
Views: 1987

Liquid fuel tank pressurised with compressed air?

Hi again, I know liquid fuels can be safely pressurised (given appropriate vessels / plumbing) with CO2 or nitrogen. Would it be safe to pressurise a gasoline / diesel fuel tank with regular air compressor, or will it explode? (i.e. is compressed air in a fuel tank somehow more dangerous than ambien...
by vhautaka
Tue Jan 20, 2004 8:57 am
Forum: Valveless pulsejet forum
Topic: Anybody have data/experience on tube-in-tube engines?
Replies: 11
Views: 5761

It's rare that someone posts a drawing of what does not work, they usually just stop talking about it and move on. I think a whole section should be devoted to "what does not work". good idea! Though practically speaking it's much more fun to work the next great idea than document the failure! Docu...
by vhautaka
Mon Jan 19, 2004 4:50 pm
Forum: Valveless pulsejet forum
Topic: Anybody have data/experience on tube-in-tube engines?
Replies: 11
Views: 5761

Mike, looking at those Tharratt contraptions, they seem to have isolated the intake area pretty well from the ignition / combustion area. Probably that helps with thermal expansion trouble. Also the huge size of Tharratt intake may be compensated by the 180 degree turn. Also I know their patent coul...
by vhautaka
Sun Jan 18, 2004 8:22 am
Forum: Off topic forum
Topic: Russian Flying Saucer
Replies: 9
Views: 4825

Uh, I stand corrected. :) Thanks. This seems to do exactly the opposite than I thought, using vortex chambers to suck in air at strategic places instead of blowing air over the airfoil. The effect, as I understand it, is essentially the same - causing steady flow over the plane's surfaces even when ...
by vhautaka
Sat Jan 17, 2004 10:57 am
Forum: Valved pulsejet forum
Topic: No Weld Pulsejet
Replies: 32
Views: 15278

How about using that inner tube to heat fuel?

Or even to boil water, the vapor to be injected into the exhaust?

Oh yeah, that would require welding again.... or would it?


- ville
by vhautaka
Sat Jan 17, 2004 10:09 am
Forum: Off topic forum
Topic: Russian Flying Saucer
Replies: 9
Views: 4825

The profile of the flying vehicle body ensuring laminar airflow in the boundary layer of the larger part of upper surfaces of the vehicle, permitting to install on the upper part of stern the vortex boundary layer airflow control system thus ensuring steady airflow around the vehicle body. The vehi...
by vhautaka
Sat Jan 17, 2004 12:55 am
Forum: Off topic forum
Topic: Russian Flying Saucer
Replies: 9
Views: 4825

A Coanda lifter! Well, maybe just a Coanda drag-reducer. If I understood correctly, the "spooky vacuum trick" is to use the engines with special, strategically-placed, flat nozzles to accelerate air on the wing surface. This flow, moving fast and presumably being warm and turbulent, will stick to th...
by vhautaka
Fri Jan 16, 2004 11:45 pm
Forum: Valveless pulsejet forum
Topic: Anybody have data/experience on tube-in-tube engines?
Replies: 11
Views: 5761

Thanks guys! Great! Mike, about heat expansion: It only now occurred to me that the expansion is so severe. The patent suggests using heat resistant steel, ceramic coatings and whatever... the most accessible suggestion is using longitudinally corrugated tubes. This might be yet another reason (I've...
by vhautaka
Fri Jan 16, 2004 2:07 am
Forum: Ramjet forum
Topic: Pop Sci Ramjet
Replies: 7
Views: 6620

See "estatorreactores" at www.pulsorreactores.com. There's at least one plan that seem to be a pop.sci. or similar article. The aluminum fuel tank / combustor thing gives me the creeps... It seems dangerous, unstoppable and yet somehow almost as elegant and self-contained as a solid fuel rocket. The...
by vhautaka
Fri Jan 16, 2004 1:06 am
Forum: Valveless pulsejet forum
Topic: Anybody have data/experience on tube-in-tube engines?
Replies: 11
Views: 5761

Bill,

Unsuccessful in which way? Run erratically, never pulsate at all, explosions..?

May I ask you more about these experiments? What fuels, what engine sizes approximately? Big, small?


Cutting and trying will commence in one week, and I'll post any results.


- ville
by vhautaka
Thu Jan 15, 2004 11:01 pm
Forum: Valveless pulsejet forum
Topic: Anybody have data/experience on tube-in-tube engines?
Replies: 11
Views: 5761

Anybody have data/experience on tube-in-tube engines?

Does anyone know workable dimensions or the needed equations for a Tharratt engine or similar? Patent numbers, anything? Or, if these have ever been tried with a full-length augmentor shroud? As it is arguably the easiest engine to build (even for non-welders), I would think there have been some exp...
by vhautaka
Thu Jan 15, 2004 9:07 am
Forum: Valveless pulsejet forum
Topic: Another variant of a valveless pulsejet. COMMENTS???
Replies: 8
Views: 5262

Yep, even a couple of drops ether in a plastic bottle give enough blast to hurt human ears. :) My most successful "potato gun" type experiment was a thick-walled plastic bottle with a trigger-type stove/barbecue lighter through the bottom, and a tight-fitting cardboard tube glued to the bottle mouth...