Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: chiralSPO on 22/09/2013 15:20:03

Title: Would a blow torch work on Titan?
Post by: chiralSPO on 22/09/2013 15:20:03

Titan's atmosphere is mostly nitrogen, but almost 2% is composed of organic compounds (mostly methane, with some ethane, acetylene and traces of heavier compounds like benzene). Could oxygen by itself be used to fuel a blow-torch in such an atmosphere? How about a combustion engine? Fuel cell?

Title: Re: Oxygen torch on Titan?
Post by: CliffordK on 22/09/2013 19:42:47

On Earth, the LEL (lower explosive limit) for Methane is 5%, UEL (upper explosive limit) is 15%.  However, I assume that is calculated with a 20% oxygen atmosphere.  The LEL for Hydrogen is 4%.

Thus, 1.6% of Hydrogen & Methane wouldn't be explosive with low concentrations of oxygen.  It may still burn with 100% oxygen.  However, that would imply ideal mixing of the gas. 

It may be difficult to mix, say 100% Oxygen + 98.4% Nitrogen + 1.4% Methane + 0.1% Hydrogen in any fashion to still come up with a flammable mixture.  Say one uses a 50% mixture of oxygen, then one gets 50% Oxygen, 49% Nitrogen, and 0.7% Methane, 0.05% Hydrogen which may not be flammable.  With higher concentrations of oxygen, the Methane concentration would be further reduced.

Undoubtedly if one was building a torch, one would benefit by some kind of a mechanism to concentrate the hydrogen and methane.

How uniform is the atmospheric mixing of gases on Titan?  Methane and Hydrogen are significantly lighter than Nitrogen which could lead to some stratification of layers.