Combustion in Reducing Atmosphere?

[stevebowers]

Another addition to the data has now been added by Grant Hutchison;
http://cosmoquest.org/forum/showthread.p...ost2261587

you need a flammability diagram for methane. The gases have to be present in the volume ratios shown, so atmospheric pressure is irrelevant except that higher pressure mixtures will produce bigger bangs or hotter flames.

In your example of an oxygen jet, combustion can take place at the edges of the jet where the oxygen has turbulently mixed with the atmosphere to produce a mix in the combustible range. New combustible mix forms constantly at the boundaries of the jet, and is heated by the combustion process until it combusts, too. The combustion can't spread into the jet or out into the atmosphere, because the mix shifts outside the combustible zone. So you produce a self-sustaining flame which is essentially an inside-out version of a methane jet burning in air.

I love triangular graphs like this.