www.pulse-jets.com

I'm hearing the sound loud and clear ... so while there's obviously something odd happening the sound IS there ...

John

Congratulations on the successful run ... :)

John

Smallest I've heard of was a 4 inch valveless that would run on Hydrogen at about 2000Hz. If I recall it gave damn all thrust but make a VERY loud noise and got bright, cherry-red hot.

John

Thanks Loco ... well werth (*EDITED* or even "worth") a thought ... :)

John

How well does this "Ugly Stick" design work? Strikes me it might serve for me as well, as an "established design" to get running before investing in welding kit for the "Squirrel".

John

The rapid and intense blasts of extremely hot air are excellent for cooking meat. Now that's a good one. Police Officer - Excuse me, Sir. We've had complaints about a horrendous, roaring noise coming from your back garden that can be heard at least two miles away. Me - Oh? I'm sorry. I was just try...

BBQ?

Cook your sausage in 1.38 seconds ... ;)

John

I'm sure I saw a video somewhere about an attempt to produce a 2 inch long pulse-jet. The researchers started with a 15 incher, then "approximately halved" it to 8 inches (ran fine on hydrogen) the halved it again to a 4 inch (which also ran). I don't think they'd achieved the goal of 2 inches, but ...

I'll have a look and see what's available around here ... :) ... And compare with gas ...

John

It is ... Kinda makes me wish Chicago was somewhere close to Surrey ... :(

John

Ah ... another thing to consider ... It's not good being a complete welding newbie - the possibility of mistakes!

I shall see what the gas bottle would cost me.

John

*EDIT* OK ... I've looked at oxy-acetylene "sets" and I see one advertised, new and at a price that seems reasonable consisting of:- (and here I'm cut-n-pasting) 1 x 5mtr Set of Oxy-Acetylene Welding Hose (With safety fittings fitted) 1 x Oxygen S-150 2 Gauge Regulator 1 x Acetylene S-22 2 Gauge Reg...

Thanks lojbeck, Yes, certainly another route to consider. I'll look into gas equipment - but having said that I have an "aversion" to toe idea a shed full of gas cylinders (I'd rather not even have a propane one there if I could avoid it, unfortunately that's just not going to be possible) so I woul...

If you're wanting a "desktop engine" might I suggest you don't go "steam" at all, but go for a "Stirling" hot-air engine? Far more "interesting" and no high pressures on your desk. Oh - and almost instant start-up with no need for a boiler to boil and pressurize.

John

OK ... my "Squirrel" valveless pulse-jet design is reaching the time when it needs to be tried "in the steel", so the time has come to build it! This is somewhat hindered by the fact that (a) I have never welded in my life ... well, actually I have, but it was with oxy-acetylene and years ago ... an...