X-Jet

[HattoriHanzo]

Wonder if anyone knows about this project?

http://www.aardvark.co.nz/pjet/xjet.shtml

I have attempt to reach Mr. Simpson for a couple off months now without any contact.

[Bruno Ogorelec]

I would advise you to search this forum for mentions of Bruce Simpson. He and his projects have been mentioned very often.

[Anders Troberg]

And his business ethics...

[HattoriHanzo]

Ok, I have read some threads here, yeah business ethics... :(

I was interested to talk about the thermodynamics of the X-jet. But now it seems to be an ordinary valved pulsejet and a man who sits on his high horse.

[Bruno Ogorelec]

I was interested to talk about the thermodynamics of the X-jet. But now it seems to be an ordinary valved pulsejet and a man who sits on his high horse.

The valved version of the X-Jet is one thing. Few things about it are ordinary. It is the best valved engine I know of, period.

The valveless X-Jet that followed is anyone's guess, as Bruce never (to the best of my knowledge) divulged anything about it to the outside world, with the possible exception of investors that he had reportedly negotiated with. The only information anyone else has about it is conjecture, so that it's a somewhat fruitless topic for discussion.

[Anders Troberg]

Yep, there is little doubt that he has made valuable contributions to this field, but he has also drawn some unwanted attentention to it and has a personality that may not make him the perfect poster boy for pulse jet development.

One of his worst "crimes" was that his site got me hooked on pulse jets, so he is partially responsible for me being here asking stupid questions. The other half of that responsibility lies with Bruno's excellent (even if he claims it's largely outdated) paper on valveless pulse jets, which gave me a nice kickstart into understanding the subject. And now I just can't stop!

[Bruno Ogorelec]

Ha-ha-ha.... Anders, as people used to say, you can lead a horse to the water, but you canot make it drink. You took that drink yourself. But, I am glad you did.

[Anders Troberg]

You made the water look tasty.

To be honest, before I read your paper, I had just seen some sketches and photos of lockwoods and the jets on the SRL hovercrafy without any explanation at all, and I just could not figure out how they worked. I mean, how intuitive is it that a U-bent empty tube with a bulb on one leg would produce anyting useful, least of all thrust? Your paper made things start to make sense for me.

I still don't understand clearly (at least not in detail) how they work, but now I'm at least ignorant with confidence.

[Najm]

Somebody on this forum tried to make something like an x-jet.
I've forgotten who tried to do it but he wasn't successful in making it work as far as i can remember, and I lost that thread and don't know what happened afterwards.

[larry cottrill]

... but now I'm at least ignorant with confidence.

"Ignorant with confidence." Man, when you're happily walking in The Land of the Roaring Pipes, that just about says it all.

I'll never forget finally getting my first sustaining engine, the Elektra I, to run. It finally works, and you stand there with your mouth open thinking, "HOW can it do that?" And this is AFTER you think you finally understand the basic theory. There's a 'gut level' component to the experience that you really can't explain to anyone who hasn't struggled with it.

L Cottrill

[Anders Troberg]

Somebody on this forum tried to make something like an x-jet.
I've forgotten who tried to do it but he wasn't successful in making it work as far as i can remember, and I lost that thread and don't know what happened afterwards.

I think the problem is that little is know about the X-jet, so any guess about the design is probably a fair bit off the target. The way things are going for Bruce Simpson now, I'll doubt he'll be able to continue to develop it much further.

[Eric]

Somebody on this forum tried to make something like an x-jet.
I've forgotten who tried to do it but he wasn't successful in making it work as far as i can remember, and I lost that thread and don't know what happened afterwards.

I made something which I suspect is the principle of the X jet. When I originally posted a paint drawing schematic of the skewed engine layout everyone was quick to point out that it probably wouldnt work. I think bruno would probably be the only person who would be able to say if it was or was not.

Eric

[Eric]

Here is a quick 5 minute unskewed diagram of the 180 degree out of phase valved engine.

When I posted the first diagram of the engine I had the valve plates flat, and both in line with eachother, everyone though the valves would have to travel too far but didnt seem to pick up on the fact that if they were made V shaped the internal resistance and travel distance is greatly reduced.

This engine layout seems to fit most of the xjet claims and definately the appearance.

Eric

[Stuart]

everyone though the valves would have to travel too far but didnt seem to pick up on the fact that if they were made V shaped the internal resistance and travel distance is greatly reduced.

Eric

I think the real problem would be the mass and strength of the rigid flapper (you couldn't really call it a reed). Might work.

[Bruno Ogorelec]

I still don't understand clearly (at least not in detail) how they work, but now I'm at least ignorant with confidence.

Well, if it makes you feel better, I don't understand them much better myself. Not that it matters much. They are like my wife -- I love her very much, virtues and foibles and all, but have long ceased to hope I will ever quite understand what goes on in her mind.