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Pulse jet tea kettle

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68 pointshansc26 comments

This brought a huge grin to my face. I think I'll be smiling for the rest of the day, just thinking about it. It's wonderful to see people tinker and explo(r|d)e stuff!

I probably watched this 10 times in a row while giggling like an idiot. Made my day and sparked interest in pulse jets. So I found:

A pulse jet "organ": http://www.youtube.com/watch?v=-zU4u7SSDKw A pulse jet / amateur jet engine forum: http://www.pulse-jets.com/

Great stuff!

Similar thoughts here. Still don't quite understand why the brits like their tea with milk.

Er, it's a bit arbitrary; if many of them have grown up drinking tea with milk, they'll probably tend to keep drinking tea with milk.

Also, my observation (from ~5 years living in Britain, but YMMV, etc, etc) is that most people just use fairly cheap tea, in teabags, brewed fairly strong. If you don't add milk, it can be a bit nasty.

[Sure there's plenty of nicer tea available, and people who care about that sort of thing, but it's not what the average Joe is using.]

I drink (black) tea with milk. So here's a _very_ anecdotal/hypothetical thought: my brother switched to drinking black tea without milk. A couple of years later, he had a kidney stone; and the doctor claimed it was the tea.

Some of the tannins that give the tea its color are small enough to get into the blood stream, but get caught in the kidney, possibly leading to stones. So if you add milk, the big fat molecules of milk trap these, which prevents them from getting caught in the kidney; hence no stones.

I could be wrong...

You could be right. I've been drinking black tea no milk/sugar for 10+ years, no kidney stones yet. Which would make me superhuman, and I'd like that possibility even if it is quite slim.

You're scaring me. I drink a LOT of tea. I usually go through 8-10 tea bags in a day (always black, no sugar or milk). I've always worried about the tannins and the kidney stones. No problems so far!

I was hoping this would involve some sort of crazy energy transfer like cavitation heating or something. Still a neat project, but I'm sure there are better things to do with a functional pulse-jet.

This led me to wonder: what's the fastest (and at least hypothetically non-widespread-destructive[1]) method of boiling a kettle-sized volume (say, 1.5l or so) of water[4].

1.5l * 4.2kJ/l/K * (100 - 20)K =~ 500kJ energy required.

Exactly what sort of (practical) coupling achieves the most effective transfer is the purpose of the challenge.

Thoughts?

[1] in the spirit of the George Goble[2] approach to BBQ ignition optimisation using liquid oxygen[3]

[2] https://en.wikipedia.org/wiki/George_H._Goble

[3] http://www.humournet.com/collage.archives/collage096.txt

[4] Trickery involving reduced pressure to achieve low-temp boiling are considered cheating. I"m not sure what the benchmark pressure would be though, since you'd probably want a high-pressure heating vessel in case you overshoot and vaporise it.

The trick is to maximize surface area. Taking this to it's logical conclusion, the fastest way to boil that much water probably involves aerosolizing it into a rather large and hot flame. Perhaps that LO2/charcoal flame. ;)

If that is cheating, then the solution is probably somewhere in the middle I suppose.

Another creation by Colin Furze here: the flame throwing scooter, which incidentally got him arrested.

http://www.youtube.com/watch?v=0UNr1XClnec

I wish I had the time to do pointless and dangerous things like this.

I wish I had the tools and space to do stuff like this.

I'd suggest looking for a local hackerspace. You can find a fairly comprehensive list here: http://hackerspaces.org/wiki/List_of_Hacker_Spaces

There you'll likely find the tools, space, and most importantly a community of people willing to give you advice :)

I suspect part of the reason he got in trouble for the scooter is that neither did he. ;)

He specifically addresses this on his website. He doesn't have good tools or much space either. He used to do these things in his bedroom at his parents house because his dad wouldn't let him use the garage.

I found the insane guy immensely entertaining.

And there is always the Jet powered beer cooler : http://www.asciimation.co.nz/beer/

So now you can cook things or freeze them :-)

Can someone explain this in laymen terms please? looks cool though.

A pulse jet is an incredibly simple kind of jet engine, usually with no moving parts. They were used on the V1 flying bomb in WWII. Wikipedia probably explains it better than I can http://en.wikipedia.org/wiki/Pulse_jet_engine . The version in this video is a valveless pulsejet.

Basically, he put the combustion chamber of the pulse jet in a tea kettle, so instead of just glowing red hot when it's running, it heats water. Also, it's awesome.

Also, google "jam jar pulse jet." I made one in about 5 minutes last summer. Lot of fun, but scary when you realize it's a hot flame contained in a glass jar.

Oookay, that's just insane.

I think I might try it.

A pulse jet is basically the predecessor to jet engines as we usually think of them, but they work more like the internal combustion engines we have in cars. They are basically combustion Chambers that are set up to emit the exhaust in one direction for thrust and reset for the next explosion.

The rapid fire explosions create a buzzing noise, and a decent amount of heat.

He's using the waste heat from an esoteric jet engine design to warm up his tea. Because he can.

Looks dangerous. I wouldn't use it.

"Looking at Goble's video and photos, I became, as an American, all choked up with gratitude at the fact that I do not live anywhere near the engineers' picnic site." - http://www.davebarry.com/misccol/charcoal.htm

Does my heart good to see there are still some hardcore tinkerers out there, though.

You will be happy to know that the site mentioned in the article is still available: http://web.archive.org/web/19961227054127/http://ghg.ecn.pur...

Is that the only reason you wouldn't use it? ;)

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