Calculate Flame Height: Material and Output Hole Size

In summary, the height of a flame can be calculated by considering the material being burnt, the area of the flame output hole, and the internal pressure of the lighter. The velocity of the butane escaping will also play a role, along with the time it takes for the molecule to burn. The fuel and air ratio will also affect the flame height, as demonstrated by the difference in effect of an acetylene torch with varying amounts of oxygen. Adjusting the air intake on a Bunsen burner can also show the same effect.
  • #1
dyiu9632
2
0
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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  • #2
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.
 
  • #3
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.
 
  • #4
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:
 
  • #5
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.
 

1. What is flame height and why is it important to calculate it?

Flame height is the distance between the base of a flame and its tip. It is important to calculate flame height because it can provide valuable information about the behavior and intensity of a fire, which can be useful for fire safety and prevention measures.

2. How is the material of the fuel source related to flame height?

The material of the fuel source can greatly affect the flame height. Different materials have different burning characteristics, such as heat output and burning rate, which can impact the size and intensity of the flame. This is why it is important to consider the material when calculating flame height.

3. What role does the output hole size play in flame height?

The output hole size is another important factor in calculating flame height. This refers to the size of the opening from which the fuel is released. A larger output hole size will result in a larger amount of fuel being released, leading to a higher flame height.

4. How do you calculate flame height?

To calculate flame height, you will need to know the material of the fuel source, the output hole size, and the heat output of the fuel. These values can then be plugged into an equation that takes into account the burning rate and heat release rate of the fuel to determine the flame height.

5. Are there any safety considerations when calculating flame height?

Yes, there are several safety considerations to keep in mind when calculating flame height. It is important to wear proper protective gear and follow safety protocols when working with fire. Additionally, the results of the calculation should be interpreted carefully and used responsibly to prevent potential fire hazards.

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