The stove that may well kill me!

[mick91]

I've had an idea, and those will one day be my last words. But hopefully not due to this idea. I've built a traditional pulse jet once before, it was a roaring success, even if it did appropriate a rightful noise complaint from my neighbors. But I've recently come across a tin can self contained self aspirating kind of pulse jet that I think may have implications as a stove [video]https://youtu.be/bTOU-2aSmHE[/video] anyone that's ever built or been around a pulse jet will know that the heat they kick off is absolutely tremendous in a very short space of time, far hotter than any stove I've used. Im aware it's a novelty but something to have a crack at and might be good fun. And if nothing I will have the loudest stove in history!
Now where did I put that nitromethane ... Wonder what happens when you put it in a trangia

 

[Blundstoned Love]

Pulse Jet?

As in Doodlebug?

"Farewell and adieu to you fair Spanish ladies..."

 

[mick91]

Pulse Jet?

As in Doodlebug?

"Farewell and adieu to you fair Spanish ladies..."

That's the one. They're easy enough to build. The traditional shape, but that tin can model may well be viable as a stove. Not hugely controllable and I'm talking filling a tin can with a liquid explosive and lighting it here but I can't see a reason it wouldn't work

It's not a true pulse jet because of how it works but it's a very close approximation

 

[dewi]

but I can't see a reason it wouldn't work

There is always the reason that it might explode and fill you with shrapnel I suppose, but other than that I can't think of a reason either!

 

[mick91]

There is always the reason that it might explode and fill you with shrapnel I suppose, but other than that I can't think of a reason either!

Ahh see way ahead of you. The tin can ones need a cooling jacket to work, so standing it in a pan of water is the plan (so it'll boil much like a Kelley kettle) so if it does go Chernobyl it SHOULD soak up some of the explosion and stop the shrapnel... That or drastically increase the critical impulse making fragments of the pan into larger pieces of shrapnel with much more velocity... But I'll cross that bridge when I come to it

Sent from my LG-D855 using Tapatalk

 

[mick91]

My other little safety aspect is I intend to use a golden syrup tin. At least then if it does burst it'll do so in a predictable way (blow the lid off) so the nitromethane will flare then burn away no more eventfully than a can of unconfined petrol. Might be me being a bit H&S paranoid there but anyone that thinks things that go bang are in any way "fun" has never worked with em!

 

[Bishop]

It's not a true pulse jet because of how it works but it's a very close approximation

My thermodynamics is a very rusty but if I recall correctly the method of operation is roughly the same as a Two-Stroke engine exhaust with the sound pulse from the detonation reflecting around the open hole and bouncing back causing a partial vacuum that draws in fresh air. Definitely something to mess around with on those long winter nights.

 

[mick91]

My thermodynamics is a very rusty but if I recall correctly the method of operation is roughly the same as a Two-Stroke engine exhaust with the sound pulse from the detonation reflecting around the open hole and bouncing back causing a partial vacuum that draws in fresh air. Definitely something to mess around with on those long winter nights.

That's pretty much exactly how it works actually. Only difference being the cooling jacket is needed on tin can ones to increase the partial vacuum with a temperature gradient. Traditional pulsejets do so because they're a clever shape and don't need the coolant. Ingenious really

 

[dewi]

Ahh see way ahead of you. The tin can ones need a cooling jacket to work, so standing it in a pan of water is the plan (so it'll boil much like a Kelley kettle) so if it does go Chernobyl it SHOULD soak up some of the explosion and stop the shrapnel... That or drastically increase the critical impulse making fragments of the pan into larger pieces of shrapnel with much more velocity... But I'll cross that bridge when I come to it

Sent from my LG-D855 using Tapatalk

Thinking about it, that fella on YouTube has got away with making multiple pulse jets and he's still alive. Scarred for life mind you, but alive

If you're going to do it Mick... be a pal and wear a flak jacket or something... we've got some wild camping to do next year, and it'll be a right pain if you're full of holes and leaking blood everywhere... we'd need a bigger tarp!

 

[mick91]

Thinking about it, that fella on YouTube has got away with making multiple pulse jets and he's still alive. Scarred for life mind you, but alive

If you're going to do it Mick... be a pal and wear a flak jacket or something... we've got some wild camping to do next year, and it'll be a right pain if you're full of holes and leaking blood everywhere... we'd need a bigger tarp!

I reckon it should be safe enough to be honest. Burns at worst I think.

Aye I'll put a yellow pages down my jumper that'll stop it! Although let's be honest Dewi I needed a bigger tarp anyway! Never know this might revolutionise camp stoves everywhere. Although when people worry about carrying meths I'm not sure how happy they would be carrying NM, never mind the fact it kicks off nitric acid vapour when it burns

 

[dewi]

I'm trying to picture you with a balaclava, a machete and a pulse jet-powered stove... do you think anyone will approach you where we next camp out?

Totally agree you need a bigger tarp... half considered buying you the smoke house one that twodogs is selling for Christmas... but whatever you're wearing above your head this next year, I personally reckon it would be better if it wasn't covering a scarred or 'holed' individual.

All for mad ideas... but what happened to our steam-powered mobile phone charger? That was a goodun! And slightly less dangerous than taking a pulse jet into the woods!

 

[mick91]

I'm trying to picture you with a balaclava, a machete and a pulse jet-powered stove... do you think anyone will approach you where we next camp out?

Totally agree you need a bigger tarp... half considered buying you the smoke house one that twodogs is selling for Christmas... but whatever you're wearing above your head this next year, I personally reckon it would be better if it wasn't covering a scarred or 'holed' individual.

All for mad ideas... but what happened to our steam-powered mobile phone charger? That was a goodun! And slightly less dangerous than taking a pulse jet into the woods!

Haha. Along with a riot helmet and ballistic shield just to make a brew!

Aye I got a bigger one ordered the day I got back from there it was far too small the one I used! Should be a laugh out next wild camp though really looking forward to it.

Aye I got the dynamo and everything connected and it was giving me current out of the usb connector but I think it needs torque as well as revvs. The flywheel of my mammod steam engine didn't produce any when a cordless did it quite nicely. Back to the drawing board methinks!

 

[dewi]

Aye I got the dynamo and everything connected and it was giving me current out of the usb connector but I think it needs torque as well as revvs. The flywheel of my mammod steam engine didn't produce any when a cordless did it quite nicely. Back to the drawing board methinks!

Needs gearing... I can cut some gears out if you have some rough sizes??

 

[mick91]

Needs gearing... I can cut some gears out if you have some rough sizes??

It's already geared 1:4 and that turns too slowly, direct drive didn't have enough torque. Maybe a more powerful turbine is the way so I'm looking into that in the new year

 

[Bishop]

Sounds like fun, how are you regulating the output voltage?

 

[mick91]

Sounds like fun, how are you regulating the output voltage?

Eventually it would have been some kind of inverter in line but getting it to generate a current was the first priority

 

[Goatboy]

Have you seen the videos of the chap who made the doodlebug remote control model? Proper working propulsion system. Very cool.
I like the sound of your stove though, would make an awesome tandoori oven, cook things faster than a microwave.

Sent via smoke-signal from a woodland in Scotland.

 

[mick91]

Have you seen the videos of the chap who made the doodlebug remote control model? Proper working propulsion system. Very cool.
I like the sound of your stove though, would make an awesome tandoori oven, cook things faster than a microwave.

Sent via smoke-signal from a woodland in Scotland.

I have! Hell of a model that one.
Aye I think the stove is genuinely viable to be honest

 

[johntarmac]

Maybe two yellow pages Mick, falsetto coming out of a balaclava wouldn't really project the appropriate aura.

So am I reading this right, we're going to have a steam engine AND a doodle-bug at out next meeting? Fandabbydosey!!

 

[dewi]

Maybe two yellow pages Mick, falsetto coming out of a balaclava wouldn't really project the appropriate aura.

So am I reading this right, we're going to have a steam engine AND a doodle-bug at out next meeting? Fandabbyeffingdosey!!

We were s'posed to be having the steam engine at the last meet... but there is a problem getting the dynamo up to speed for charging.

Converting from the dynamo to the mobile is easy enough... we worked out you just use a standard charging unit... has everything needed.

I still reckon some fancy gearing will do the trick... problem is what size of gears are needed to get the rpm? Bicycle wheel size?