www.pulse-jets.com

I think you could still get it to work.

Guess I will have to join in here; I was rummaging around in my private dump ( garage ) and found a glue jar ( steel vessel ) it went to the drill press, I added some fuel, It made a pleasing little zip.

Grinnnnnnnnnnn........

Found a tube from a lamp ( with coupler and nut ) and drilled 2 intake ports and put the tube on the original large port, louder zip!

I was rummaging for carburetor parts when I ran out of time...


Then I bump into this thread again This time I read. Pictures will follow.

Longest sustained operation approx. 7 seconds. No cooling.

zip = hum or putt putt?

I guess a loud purr would be apt. Forgot the camera today. I will try to find a way to get audio.


Edit; No that does not do it:

There is the usual starting whoosh followed a Deep slow purr that increases in both volume and frequency.

It does accelerating putting I guess !??!?!?!?!

The no cooling is some what misleading the fuel is old R/C aircraft fuel, 50/50 + oil That's Nitromethane and Methanol and a trace of oil.
Evaporating this stuff cools things some...

Naphtha also worked, not as well.

Ok final edit ( I hope ); Approximate dimensions.

CC: 2"ID x 3" long
Tail Pipe: 16" x 3/8"ID
Vents: 1/4" qty 2

Cheers

Wow, very interesting! 16" snorkel on a 3" depth jar . . . and a 3/2 CC aspect ratio. I'm really looking forward to seeing a photo of it and how the vents are arranged.

Did you try "HEET" in the yellow plastic container (methanol) or denatured alcohol?

vturbine wrote:Wow, very interesting! 16" snorkel on a 3" depth jar . . . and a 3/2 CC aspect ratio. I'm really looking forward to seeing a photo of it and how the vents are arranged.

Done!
The whole little thing...
Vents
CC View with scale for well.... scale...

vturbine wrote:Did you try "HEET" in the yellow plastic container (methanol) or denatured alcohol?

No, but The week is young

ANd yes with the cap the CC is a bit longer I did say Approximately....

Just an update ;

Further tests indicate the following:

1) No way did this unit operate for 7 seconds. Maybe 1.5 tops It just seemed long....

2) It starts like a typical Jam jar but then briefly "locks in" like a more typical VPJ the Zip sound that it finishes with.

3) It most likely stops due to a lack of O2 not flame out.

Working on version 3 now. Do not ask about 2...

Is it putting exhaust out through the pipe, or is it just pretty much ignoring the pipe and working out of the two holes?

Is it pulsing equally in and out of the pipe like a snorkel, or is it putting out through the pipe like more normal pulsejet? Are the holes acting as inlets or dual purpose?

Have you tried it in a water bath yet, to reduce the enrichening at the end?

It's hard to tell in the photo, but I thought the pipe doesn't look like external all-thread hollow electrical stuff -- is it a different kind of pipe?

Thanks,
Steve


ps.

What about version 2?

The pipe is a lamp part and uses an internal ( read as flow restrictor ) all thread tube for mounting.

I have noted considerable out flow through the pipe.

I would say that what we have here is fast qualifying as a pulse jet. Further I suspect that any jam jar given these modifications //should// do the same.
One becomes the other.

no water bath yet.

The new one I threaded the OD of the tube to help it breathe, we shall see.... Off to test V 3.0

V 2.0, Scrap.

Ok V 3.0 with a 16" tail does not even try, so I screwed in the remaining piece of tubing ( with the inside coupler ) still not much. I then tried to unscrew the lid to put it on a new body, The glue I used as sealant prevented this.

This whole time I would give the original a flash with the torch and it would give it's usual //Foosh-purr-ZIP!!// some times //--ZIP-ZIP// and extinguish.
My thinking was that this was a breathing issue, but I tried a water jacket, Why not V3.0 had been a bust, lets see what else No. 1 could do. No effect.
Then wile still in the water jacket I attached the extra tube, giving it a 32.5" ( there is a .5" coupler sticking out ) tail.


Eureka!


Sustained operation. It quit only when deprived of O2 by my torch, which I did to preserve the glass vessel that was the water jacket. Given fuel and cool water it would probably operate indefinitely. Out of the jacket it takes a very few seconds to extinguish. Yes I had to try it.

Interesting little device this.

I still have no way to do any recording, I will endeavor to correct this deficiency.

Ghrey wrote: I still have no way to do any recording, I will endeavor to correct this deficiency.

If you have a digital still camera, most come with the ability to take short movie clips -- often explained in an ignored or missed part of the manual. With enough memory, some can actually take quite long videos. They usually put the video clip into a convenient video file, rather than putting it on tape or other media, which requires a capture and conversion to a file. So you casn just download it from the camera and post it if short enough (under 2 megabytes for this forum, or considerably larger for Youtube)

It's best to shrink any video file down to a smaller size, even if Youtube can handle a gigabyte file. Most people cannot (or will not) download a huge file just to see a couple of minutes of a pulsejet run. There are many shrinking utilities available, and even some websites that will shrink videos online for you. Videos posted to youtube can also be shrunk and if necessary changed in format on these secondary websites.

If you know all this, pardon!

Well done!
Looks like a thermojet+jar cross.
Are you still running nitro methane? I noticed the nitro stuff will run with a white flame instead of the blue seen with regular alcohols.
Joe

vturbine: Yes the camera that I have access to does have that capability, but only 30 seconds or so at a time and NO audio. The quality is also not so good.
No pardon required; I am never offended when the intent is to help.

I could give it a try just for s&g's

Joe: Yes that does seem to be what it is.

First run fuel was ,, sat out all week ,, 50/50 + oil R/C fuel. It ran down to oil and Still ran... I plan on trying some salt dried alcohol later tonight, lower octane should be a sharper note.



Cheers

It was not running as well this evening, but running so I tried to film...
Or

http://www.youtube.com/watch?v=oO4KJ_ZNcLs


Also my first attempt at iMovie...

This was a few 40 ( yes it goes 40 seconds mot 30 like I thought... ) second clips edited and pasted for a best of...