Ignition
Energy generated in flame = Ensible enthalpy Mass
Substituting quenching diameter
Substituting flame thickness
Fuel-Air
MIE (mJ)
Dependence on pressure
Methane-air
0.47
Ethane-air
0.4
Butane-air
0.34
Acetylene-air
0.03
CO-air
0.05
Hydrogen-air
0.02