question for methane gas
question for methane gas
(OP)
if we say methane gas has 5% LEL/LFL fuel concentration mix in air ....so how much percent of air need to burn the methane gas.
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RE: question for methane gas
CH4 + O2 + O2 +O2 => CO2 + H2O + H20 + H2O + H2O
1 methane to 3 oxygen
air is 28% O2,
so that's 3O2/0.28 = roughly 1 methane to 10 air
If you're trying to find the amount of methane in a mix that is needed to a reach LEL atmosphere, then 100 x 0.05 = 5 methane and obviously 95 Air => 5 cubic feet to 95 cubic feet of air, 5 gallons of methane to 95 gallons of air, etc., etc.
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RE: question for methane gas
Good luck,
Latexman
RE: question for methane gas
make it burn or explode.
RE: question for methane gas
RE: question for methane gas
David Simpson, PE
MuleShoe Engineering
"Belief" is the acceptance of an hypotheses in the absence of data.
"Prejudice" is having an opinion not supported by the preponderance of the data.
"Knowledge" is only found through the accumulation and analysis of data.
RE: question for methane gas
You can mix air with methane without being able to ignite it. Where i live they now make city gas this way. City gas has lower heat of combution pr. volume unit than natural gas. In order to avoid having to replace a lot of gear they simply mix in som air than lowers the heat of combustion to a similar value.
There is an "ideal mixture of methane and air between LEL and UEL. At this value (or close) the mixture will explode not burn. E.g. with a internal combution morotr. If your mixture is to lean or to rich (altough within LEL/UEL) you get poor combustion with low performance and lots of soot/smoke whatever.
Best regards
Morten
RE: question for methane gas
My kid is a bomb tech, I'll ask him this morning and let you know.
David Simpson, PE
MuleShoe Engineering
"Belief" is the acceptance of an hypotheses in the absence of data.
"Prejudice" is having an opinion not supported by the preponderance of the data.
"Knowledge" is only found through the accumulation and analysis of data.
RE: question for methane gas
has 5% LEL and 15% UEL (gas mix in air)
and between them is 10% .....so this mean
the 10% has more explosion than 5% and
15% (LEL & UEL )...is it correct.
RE: question for methane gas
Think of your gas stove. It fires right off. If you suppress the ignition and gas spreads through the house and "hits" the pilot light in water heater - GA-BOOM
RE: question for methane gas
Your questions lead me to believe you want to know how to optimize the explosive force of a methane/air mixture. What is your application or concern?
Good luck,
Latexman
RE: question for methane gas
I don't think that anyone has ever said that before in the history of saying stuff. I see some minor differences in flame temperature as you go from LEL to UEL, but the differences are really small.
David Simpson, PE
MuleShoe Engineering
"Belief" is the acceptance of an hypotheses in the absence of data.
"Prejudice" is having an opinion not supported by the preponderance of the data.
"Knowledge" is only found through the accumulation and analysis of data.
RE: question for methane gas
RE: question for methane gas
From an internal combustion engine point of view, the most power is created for a given amount of air when the amount of fuel is slightly greater than the stoichiometric ratio would give. How much richer depends on how well things mix, how hot the surrounding surfaces are, etc. This results in a condition where all the oxygen is reacted, but you don't have so much fuel left over that you "soak up" lots of the released heat. Having no leftover fuel means that you have leftover O2, since the molecules don't actively seek each other out but instead rely on chance encounters to react.
In the sense of "most powerful explosion" there is likely another factor at play, and that's how fast the flame will propagate (which can dictate what pressure is achieved within your container). It's not necessarily the case that the mixture which releases the most energy during combustion will also achieve the highest pressure, as your container may change shape/size during the process, or you may lose some of your reactants through various leak paths, either way favoring faster burns. There may be some air/fuel ratios which will tend to self-ignite when the pressure and temperature get high enough but before the flame actually arrives, resulting in multiple flame fronts and faster combustion.