Calculate Flame Height: Material and Output Hole Size

AI Thread Summary
Calculating flame height involves understanding the relationship between the material being burned, the area of the flame output hole, and the internal pressure of the lighter. As a lighter empties, the decreasing internal pressure results in a shorter flame due to reduced butane velocity. The exit velocity of butane is influenced by both the pressure in the canister and the size of the output hole. Additionally, the air-to-fuel ratio plays a critical role in flame characteristics, as demonstrated by variations in acetylene torches with different oxygen levels. Overall, flame height can be estimated using the formula d=v*t, factoring in burn time and combustion dynamics.
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Just curious: Is there a way to calculate flame height given the material being burnt and the area of flame output hole (for example a lighter with adjustable flame height)?
 
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I would expect it to depend on the internal pressure in the case of the lighter. This would explain why the flame of a lighter gets shorter as it empties. The velocity at which the butane escapes from the lighter will depend on the pressure of the butane canister and the size of the hole it is escaping from, once you have the exit velocity you'd probably need some number representing how long it takes the butane molecule to burn, on average, then you can just do d=v*t to get an idea of how tall the flame will be.
 
The nature of the fuel itself, and the air/fuel ratio should be of significance as well. I guess that the fuel part is covered by knowing how long a molecule takes to burn, as dice mentioned. As for the air... consider the difference in effect of an acetylene torch at constant pressure with differing amounts of oxygen fed in.
 
Danger said:
As for the air... consider the difference in effect of an acetylene torch at constant pressure with differing amounts of oxygen fed in.

Um... not all of us have acetylene torches to play around with. Not that I'd turn one down, mind you :biggrin:
 
If they still make Bunsen burners the way they did when I was in school, you can get the same demonstration by adjusting the air intake on the bottom.
 
I think it's easist first to watch a short vidio clip I find these videos very relaxing to watch .. I got to thinking is this being done in the most efficient way? The sand has to be suspended in the water to move it to the outlet ... The faster the water , the more turbulance and the sand stays suspended, so it seems to me the rule of thumb is the hose be aimed towards the outlet at all times .. Many times the workers hit the sand directly which will greatly reduce the water...
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