Calculating Gas Expansion Ratio for Fireball Formation

[burnit]

Hi All,

How to work out the expansion ratio of a gas fireball.

Eg:
Just say we have a ball of gas-- no container, 1 liter in volume suspended in mid air & we ignite it, how far would the flame front extend to form the fireball, what volume would it occupy once ignited?.

An example of the equations would be helpful, i haven't specified what gas, density etc etc as i am not sure exactly what is needed to calculate this.

Thanks

 

[burnit]

Just to elaborate a little further on the above questions as it may have been taken for an out of the blue query--not so & any help would be greatly appreciated.

We have setup an experiment on a small controlled scale to find the volume occupied by the ignition of various gasses compared to the starting volume of the gas.

In our controlled experiment we have been using a gas confinement chamber with high Elasticity so once ignition occurs the confinement chamber expands to X area & volume.
This works very well except for the tension of the elastic chamber itself, the tension increases with increasing diameter & confines the true volume change of the gas fireball in normal atmospheric conditions.

I need to be able to calculate the volume change of ignited gasses compared to our results & hence the question.


Thank You