Search found 847 matches

by tufty
Sun Nov 30, 2014 8:03 am
Forum: Valveless pulsejet forum
Topic: Wanted: plans for a 10-20Lb valveless PJ
Replies: 16
Views: 3607

Re: Wanted: plans for a 10-20Lb valveless PJ

If you scale the escopette, it becomes something else, and any ideas of the original being easy to start, running consistently, producing x thrust, running at y Hz, etc, go straight out of the window. Frequency is determined by the length of the engine and the speed of sound at running temperature. ...
by tufty
Sat Nov 29, 2014 9:52 pm
Forum: Valveless pulsejet forum
Topic: Wanted: plans for a 10-20Lb valveless PJ
Replies: 16
Views: 3607

Re: Wanted: plans for a 10-20Lb valveless PJ

scaling, especially downwards, is generally a bad idea.

here's another set of escopette dimensions

Image
by tufty
Fri Nov 28, 2014 5:24 pm
Forum: Valveless pulsejet forum
Topic: Wanted: plans for a 10-20Lb valveless PJ
Replies: 16
Views: 3607

Re: Wanted: plans for a 10-20Lb valveless PJ

You want a straight valveless? Escopette / Escopeta http://www.pulse-jets.com/phpbb3/viewtopic.php?f=3&t=627 Thanks, I actually tried looking for some Escopette stuff, and couldn't find much about it except that it was a successful engine, not much information about thrust, efficiency or maximum op...
by tufty
Thu Nov 27, 2014 5:24 pm
Forum: Valveless pulsejet forum
Topic: Wanted: plans for a 10-20Lb valveless PJ
Replies: 16
Views: 3607

Re: Wanted: plans for a 10-20Lb valveless PJ

You want a straight valveless? Escopette / Escopeta

viewtopic.php?f=3&t=627
by tufty
Sun Nov 23, 2014 7:04 am
Forum: Valveless pulsejet forum
Topic: how to set up a liquid fuled engine
Replies: 16
Views: 3871

Re: how to set up a liquid fuled engine

First I need some sort of airtight fuel resistant bladder, then the bladder is placed into a rigid tank that is pressurized, that way regular air can be used to keep the tank pressurized without having to worry about the air and fuel mixing so when I need to refuel I can release the compressed air,...
by tufty
Wed Nov 12, 2014 5:11 pm
Forum: Off topic forum
Topic: New land speed record for bicycle
Replies: 0
Views: 1075

New land speed record for bicycle

http://www.bbc.com/news/technology-30007505

333 km/h, hydrogen peroxide rocket power.

https://www.youtube.com/watch?v=pnKxLZCa-ks

...and he looks like riff-raff.
by tufty
Wed Nov 12, 2014 5:05 pm
Forum: Valveless pulsejet forum
Topic: Looking for plans? Look here.
Replies: 28
Views: 1664717

Re: Looking for plans? Look here.

I found a new one. It's rudimentary, but appears correct.

Image
by tufty
Wed Oct 29, 2014 7:45 pm
Forum: Valveless pulsejet forum
Topic: how to set up a liquid fuled engine
Replies: 16
Views: 3871

Re: how to set up a liquid fuled engine

As I see it, using an inert gas is to stop there being an explosive mixture in the fuel tank - but it doesn't need to be inert - as long as you're not using oxygen, acetylene, or nitrous to pressurise, your fuel tank shouldn't be a bomb waiting to happen. There is danger involved, in that you have a...
by tufty
Tue Oct 28, 2014 5:28 pm
Forum: Valveless pulsejet forum
Topic: how to set up a liquid fuled engine
Replies: 16
Views: 3871

Re: how to set up a liquid fuled engine

If you're going to have propane involved, why not use that to pressurise your fuel?
by tufty
Thu Aug 07, 2014 11:31 am
Forum: Tools and Construction
Topic: Odds and ends
Replies: 1715
Views: 273883

Re: Odds and ends

Mark, you make the wierdest pulsating devices. And I mean that in a good way :) With two elbows like that, and some creative weighting / outrigger-floating, you might be able to make a "proper" water-based snorkeller, with the entire bottle submerged and only the snorkel peeking out, periscope style...
by tufty
Mon Jul 28, 2014 7:22 am
Forum: Valveless pulsejet forum
Topic: M500 build log
Replies: 161
Views: 35684

Re: M500 build log

Aw, man, that's an awesome noise it made just before it decided to go all "burninate".

Burns are bad news. Hope they repair nicely.
by tufty
Sat Jul 26, 2014 7:01 am
Forum: Valveless pulsejet forum
Topic: Blast Compression Intake proposed design
Replies: 78
Views: 28674

Re: Blast Compression Intake proposed design

Bruno Ogorelec wrote: An old myth, too. Alas.
As they say around here, "old pots make the best soup".
by tufty
Mon Jul 21, 2014 7:48 pm
Forum: Valveless pulsejet forum
Topic: PyroJoes Recipe for Beginners
Replies: 209
Views: 1694206

Re: PyroJoes Recipe for Beginners

PyroJoe wrote:cold beverages as needed for … self medication.
That shows a disgraceful lack of scientific rigour, I'll agree.

Mind you, cold beverages are out for the moment round here, we're having a shitty summer. Turned up at work a week ago, 3°C and sleet. It's hot chocolate and oxy-acetylene weather.
by tufty
Fri Jul 18, 2014 6:51 am
Forum: Tools and Construction
Topic: Odds and ends
Replies: 1715
Views: 273883

Re: Odds and ends

Mark, you crack me up. The paintball tank in the wine bottle holder is, as they would say around here, «fantastique»