Flour Cannons

[SNDM]

This idea came to me in chemistry; Why not use flour for a combustion?

I really do not know how much energy will be produced, but if it isnt much it can always be a nerfed design.
Anyway, after researching it, I discovered that around 56g in 1m3 is explosive.
This could be metered, achamber fan could help keep it as a mist as that is optimum. Flour is also a bit easier to get hold of than, say, propane (although to be honest that really isnt saying much).

I was wondering If anyone knew more about this than I (again, not hard), any implications, any dire problems I havent realised?

Thankeye people.

[psycix]

It will be hard to make the mist being atomized very well.
I suggest two or more chamber fans (small diameter) blowing in opposite direction in order to make some air circulation going on.

Dust explosions are very hard to make, they mostly occur by accident.

But yes,
When all fuel on earth runs out, we could aways use flour.
Its a nice experiment though.

[magnum9987]

coal and charcoal when powdered create an explosion as well. It is theorized that this coal powder explosion blew up the Lusitania. So explosions from powder are possible. I am unsure however of the capabilities of baking flour as a powdered explosive.

[Davidvaini]

flour is extremely explosive when properly atomized.

However atomizing flour is extremely tricky business.

[pinkham21]

You can make flour explode but it can be dangerous. I have been taught to use it in the military and with a five pound I can bring a house to the ground. I would not recommend it.

[pat123]

I think it would hard to get it misty enough. I also think this is against the rules though.

edit: sorry not against the rules

Solid propellant: Any substance containing all the chemical elements required to enable sustained combustion without the presence of additional oxidizers. This includes but is not limited to gunpowder, thermite, and many commercial and/or homemade pyrotechnic compounds.
For this purpose, nitroglycerine, though liquid, would qualify.
For this purpose, ordinary flour, though solid, would not qualify

[DYI]

You can make flour explode but it can be dangerous. I have been taught to use it in the military and with a five pound I can bring a house to the ground. I would not recommend it

Has it ever ocurred to you what five pounds of properly mixed propane/air could do to a house? The propane alone would occupy 1.28m³, with the entire fuel/air mix occupying 28.4m³. I don't imagine something like that would have any real trouble bringing a house to the ground either. Flour isn't any more powerful than the usual spudgun fuels (although it'd be great if it was).

And have you ever actually demolished a house with flour? I can't see it being incredibly practical or reliable, although it certainly would be possible, as a pressure of only a few psi can completely level most walls.

[TurboSuper]

You can make flour explode but it can be dangerous. I have been taught to use it in the military and with a five pound I can bring a house to the ground. I would not recommend it

Has it ever ocurred to you what five pounds of properly mixed propane/air could do to a house? The propane alone would occupy 1.28m³, with the entire fuel/air mix occupying 28.4m³. I don't imagine something like that would have any real trouble bringing a house to the ground either. Flour isn't any more powerful than the usual spudgun fuels (although it'd be great if it was).

And have you ever actually demolished a house with flour? I can't see it being incredibly practical or reliable, although it certainly would be possible, as a pressure of only a few psi can completely level most walls.

Yeah, I'll second that, anyone remember that shoe store in Mexico which lost two floors when propane leaked into the basement?

[Ragnarok]

I was wondering If anyone knew more about this than I (again, not hard), any implications, any dire problems I havent realised?

Actually, not a new idea, surprisingly enough, it's been discussed here:
http://www.spudfiles.com/forums/sugar-a ... t4082.html

I know it mentions sugar, but the idea was dust fuels in general. Might be worth a read.

[pizlo]

I remember that topic. Scary isn't it?
BTW is the yellowish powder in some fire extinguisher dangerous?

[D_Hall]

Flour is also a bit easier to get hold of than, say, propane

This comment really caught my attention.....


Where do you live that flour is easier to get hold of than propane? In this small town I can think of three stores that carry flour (yes, grocery stores). Meanwhile, I can think of a dozen or more that carry propane (everything from yes, grocery stores, to sporting goods, to auto parts places).

[jimmy101]

IIRC, joannaardway did eventually get the "dust gun" to work.

Most dusts will form explosive mixtures in air. Heck, the dust doesn't even have to be flammable in the normal sense. In certain situations even iron dust will give a dust explosion.

Folks use coal dust, flour, powdered sugar, corn starch, non-dairy coffee creamer, and a bunch of other things. The most common material is lycopodium, a dried moss. The tricky part is that you have to get the dust particle sizes just right. And, you have to get the dust well dispersed in the air. And, you have to get within the materials flammability limits (just like with propane). Flour and sugar are very sensitive to the moisture level, too humid and it won't properly disperse. The lycopodium is supposed to be particularly easy to get to a combustable suspension.

Here's a college level engineering lab for the study of dust explosions.

Some pictures of a lab setup are here

Like DYI said, the energy produced in a typical dust explosion isn't all that much different than in a natural gas explosion. On a pound fuel basis it isn't even all that much different than "real" explosives. (The same can be said about propane etc.)

Heck, I'm surprised you can still get non-dairy coffee creamer on airlines. Why hasn't TSA banned it because it is a good material for creating explosions? (only partly kidding)

[potatoflinger]

It can't be too hard, this guy makes it seem pretty easy. I don't think it would be too hard to incorporate into a spudgun, but it might be a bit tricky to get the ratios right.

(and if someone made a flour cannon they could name it Shake n' Bake )

[Canuck]

I might try this.. What im thinking is placing a little flour in the chamber, close the plug shake'r up and try to ignite it lol i dunno.

[psycix]

Well, good luck
Im wondering if it will work.
Make sure to measure out the right amount of "fuel".

Maybe, if it doesnt work, try half propane and half flour.
Or, when all else fails use alot of flour and inject pure oxygen (metal chamber recommended).


What is the thermal energy (J/mol) released by burning flour?