Annular Engine Running

[ed knesl]

Finaly !!

Engine on enclosed image finaly runs. It is very, very difficult
thing to get going. Any mathematical and theoretical stipulations
did not materialized. After few different "heads" fitted, I came up
with just slightly oversized CC/Intake ( head ), than I started
inserting additional restrictors ( Just two small ones made a trick )
into intake and finaly got it ! It is extremely touchy.

Take my word, this is going to be only one of very few, if any, running annular engines.

Ed

[steve]

wow- nice work
did it run long enough to start glowing?

[mk]

Nice, Ed!

[Bruno Ogorelec]

A good-looking engine. Sorry to hear it's been a pig to get going. Wouldn't greater containment have made it easier?

[Hank]

Ed, Perhaps attached might be an improvement. What fuel are you using.

Hank
Undersecretary of Small Animals

[Mark]

I wonder if the sleeve concept is fussy from the way the air flow is allowed to enter the engine? That is, I can see it having an opportunity to chase in around the sleeve erratically, whereas with a snorkel type intake duct or ducts, the air is forced to be coherent or more timed in its arrival. Maybe the sleeve allows the inflow to fluctuate disproportionately or favor more flow on one side, varying each cycle, dampening the resonance and feedback.
Then too a sleeve has a lot of draggy surface area, but still a sleeved engine seems an interesting design to toy with.
Mark

[larry cottrill]

Ed -

Congratulations, sir! Very nice job proving that it really can be done.

I am not surprised that it's a touchy beggar - it's such a simple concept that if it was easy, there'd be some plans out there that you could just follow and everyone would be doing it.

Nice work! Please consider writing an article for me on how you got through it, pitfalls, starting tricks, etc. - whatever you want to reveal about how you got it to work.

L Cottrill

[ed knesl]

I wonder if the sleeve concept is fussy from the way the air flow is allowed to enter the engine? That is, I can see it having an opportunity to chase in around the sleeve erratically, whereas with a snorkel type intake duct or ducts, the air is forced to be coherent or more timed in its arrival. Maybe the sleeve allows the inflow to fluctuate disproportionately or favor more flow on one side, varying each cycle, dampening the resonance and feedback.
Then too a sleeve has a lot of draggy surface area, but still a sleeved engine seems an interesting design to toy with.
Mark

Mark,

I think I prevented the chase around by having four spacers for keeping
CC centered, forming paralell ducts.
Well, it runs, that means the end of headaches. What was most dificult ?
Finding the right gap forming the intake.
This engine is no Tharatt. Intake is from the back.
Qickly in, quickly out ! That was my intent.

Ed

[ed knesl]

Ed -

Congratulations, sir! Very nice job proving that it really can be done.

I am not surprised that it's a touchy beggar - it's such a simple concept that if it was easy, there'd be some plans out there that you could just follow and everyone would be doing it.

Nice work! Please consider writing an article for me on how you got through it, pitfalls, starting tricks, etc. - whatever you want to reveal about how you got it to work.

L Cottrill

Larry,

I would be more than happy to write an article, just tell me how.

Ed

[larry cottrill]

I would be more than happy to write an article, just tell me how.

Just write it as a plain text file. Be natural and conversational - just as if you were sitting here telling me about it. Or, think of some obvious questions an interviewer might ask, and answer them. Don't worry about typos, grammar flaws, etc. - I'm supposed to be an editor.

When done, email me the text file. If you have pics to email, use jpegs and try to keep them down to about 400x500 or 500x400 pixel size and only send a couple at a time (per email message is what I mean). I can't really do higher resolutions justice on a web page, anyway.

L Cottrill

[ed knesl]

When done, email me the text file. If you have pics to email, use jpegs and try to keep them down to about 400x500 or 500x400 pixel size and only send a couple at a time (per email message is what I mean). I can't really do higher resolutions justice on a web page, anyway.

L Cottrill

Larry,

If I write basic issues here, can you take it off this forum format ?
Idea was to make it available also here. So I wouldn't have to do it
twice.

Ed

[Mark]

Mark,
I think I prevented the chase around by having four spacers for keeping
CC centered, forming paralell ducts.
Well, it runs, that means the end of headaches. What was most dificult ?
Finding the right gap forming the intake.
This engine is no Tharatt. Intake is from the back.
Qickly in, quickly out ! That was my intent.
Ed[/quote]

Ed,
I can more than most sympathize with what you went through. I tried endless shapes and found the slightest tweak was the difference between make or break, and this included the season or weather. Things that ran spiffy in winter ran or barely ran in summer and even something so faint as using a similar bell with this snorkeler pictured, (that could almost hurt your ears in sound level) would fuss and fight if I used a different bell, still an inch to one half inch reduction but all bells are slightly different and as such taught me how persnickety it could be. Just the slightest difference in breathing around the neck/sleeve from different cuts in the threading made a big difference. It was almost if you were fishing and the guy next to you catching all the fish were saying to you, "you aren't holding your mouth right." It's just about that sensitive.
Mark
http://www.insideline.net/1999/pugh-1112-99.html
http://here2guide.com/articles/88/1/Are ... re-Fish%3F
http://www.couriernews.com/archivedstory.asp?ID=3109

[Mark]

One thing I wanted to mention. The first time I witnesses the above contraption of mine run, I was in a state of shock. It ran like a bat out of hell, very loud for a snorkeler. I later learned it was sleeving in air from around the skirt or bell. It ran for about 10 seconds and I was so amazed I quickly called my brother to tell him. My brother took to putting his fingers in his ears when I would go to start/light it. The way I fueled it was to pour just enough methanol in the bottom to run it for a short bit without too much to slosh and dampen feedback. The threading of about 1.5 turns on the canister was such that I could only get the bell to bite or turn a few turns before bottoming out on the neck region. That crude nearly matched threading allowed for some breathing which most likely accounted for the peppy combustion. It would also spit some alcohol mist out around the skirt of the bell from the rapid ferocity occurring in the canister.
Mark

[Mike Everman]

Ed, that is very cool! Tenacity pays off again.