CR4® - The Engineer's Place for News and Discussion®


Previous in Forum: OK, What Sci-Fi Book Would You Like to See as a Movie?   Next in Forum: Occupancy Sensor for Automobiles
Close
Close
Close
9 comments
Member

Join Date: Apr 2018
Posts: 9

MON/Methane Number

06/12/2018 12:55 AM

HI,

406.14 + 508.04*(H/C)-173.55*(H/C)^2+20.17*(H/C)^3

can any one tell me what is in above formula 406.14, and 508.04 , and 173.55 and 20.17

please need guide line to further learning .

Register to Reply
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

Comments rated to be "almost" Good Answers:

Check out these comments that don't yet have enough votes to be "official" good answers and, if you agree with them, rate them!
Guru

Join Date: Oct 2008
Posts: 41061
Good Answers: 1618
#1

Re: MON/Methane Number

06/12/2018 1:01 AM
Register to Reply
Member

Join Date: Apr 2018
Posts: 9
#2
In reply to #1

Re: MON/Methane Number

06/12/2018 1:28 AM

didn't get the answer from the link.

Register to Reply
Guru

Join Date: Oct 2008
Posts: 41061
Good Answers: 1618
#3
In reply to #2

Re: MON/Methane Number

06/12/2018 4:53 AM

It wasn't intended to "give" you the answer.

It was intended to give you a guideline to further learning.

Register to Reply Score 1 for Good Answer
Guru
United Kingdom - Member - Indeterminate Engineering Fields - Control Engineering - New Member

Join Date: Jan 2007
Location: In the bothy, 7 chains down the line from Dodman's Lane level crossing, in the nation formerly known as Great Britain, and now disconnecting ["brexit" - ugh] as Little England and Wales (not too sure about Wales bit, either). Kettle's on.
Posts: 27397
Good Answers: 730
#4

Re: MON/Methane Number

06/12/2018 5:56 AM

Without contextual information, the chances are quite slim.

__________________
"Did you get my e-mail?" - "The biggest problem in communication is the illusion that it has taken place" - George Bernard Shaw, 1856
Register to Reply Score 1 for Good Answer
Guru

Join Date: Apr 2010
Posts: 6299
Good Answers: 665
#5

Re: MON/Methane Number

06/12/2018 9:34 AM

MON = "Motor Octane Number"

(H/C) is hydrogen to carbon ratio

It's a formula for determining the equivalent octane of natural gas.

I'm pretty sure the numbers were determined by curve fitting to actual data.

http://www.globalmicroturbine.com/search/capstone/pages/chapter-10-natural-gas-fired-reciprocating-engines-power-generation-concerns-and-recent-advances-005.htm

Register to Reply
Guru

Join Date: Mar 2007
Location: at the beach in Florida
Posts: 20652
Good Answers: 1203
#6

Re: MON/Methane Number

06/12/2018 9:43 AM

..." the number of hydrogen atoms divided by the number of carbon atoms in the hydrocarbon components of the fuel."...

https://www.arb.ca.gov/regact/cng-lpg/appd.PDF

__________________
Life is like riding a bicycle. To keep your balance you must keep moving. A.E.
Register to Reply
Guru
Engineering Fields - Optical Engineering - Member Engineering Fields - Engineering Physics - Member Engineering Fields - Systems Engineering - Member

Join Date: Apr 2010
Location: Trantor
Posts: 5295
Good Answers: 634
#7

Re: MON/Methane Number

06/12/2018 11:02 AM

For what it's worth, here's a log-log plot of F(x) vs x, where x is H/C, and F(x) is the given formula.

A log-log plot seemed like the most useful graph; linear-linear and log-linear had funky axes for the info.

__________________
Whiskey, women -- and astrophysics. Because sometimes a problem can't be solved with just whiskey and women.
Register to Reply
Guru

Join Date: Apr 2010
Posts: 6299
Good Answers: 665
#8
In reply to #7

Re: MON/Methane Number

06/12/2018 8:28 PM

If the x-axis is H/C ratio and the y-axis is Octane rating, only the lower left corner of the graph is realistic. H/C for methane is 4 and it goes downhill from there. The formula is only valid for H/C = 2.5 to 4.

The OP has a sign error. MON should be

MON = -406.14 + 508.04*(H/C) – 173.55*(H/C)2 + 20.17*(H/C)3

Here is a plot:

https://www.scribd.com/document/241241715/Carbon-Hydrogen-Ratio-of-Natural-Gas

Register to Reply
Guru

Join Date: Apr 2010
Posts: 6299
Good Answers: 665
#9
In reply to #8

Re: MON/Methane Number

06/12/2018 8:57 PM

Here is a reference for the last post.

Appendix D - Methane Number and Fuel Composition

Register to Reply
Register to Reply 9 comments
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

Comments rated to be "almost" Good Answers:

Check out these comments that don't yet have enough votes to be "official" good answers and, if you agree with them, rate them!
Copy to Clipboard

Users who posted comments:

alikhankk (1); lyn (2); PWSlack (1); Rixter (3); SolarEagle (1); Usbport (1)

Previous in Forum: OK, What Sci-Fi Book Would You Like to See as a Movie?   Next in Forum: Occupancy Sensor for Automobiles

Advertisement