Author: **ramses** » Wed Jun 24, 2009 6:33 pm

I think the HGDT metering tool is flawed. I multiply mix by .61 to get propane pressure in psi.

For air, either of these work:

* psi= ((mix#-1)*14.7)+propane pressure

* psi= ((mix#-1)*14.7)+ (mix#*.61)

EDIT:

for 10x mix, I see 10*.61= 6.1psi propane followed by (14.7*9)+6.1= 138.4 psi air.

for an explanation of the .61 psi number, assume a 100cu in chamber.

the ideal mix is 4.2% of propane, so 100* .042= 4.2cu in propane

add this to the 100 cu in of air, and get 104.2.

divide this by 100 to get 1.042, which is in bar. (absolute). subtract the 1 to get relative pressure since atmosphere is nearly 1 bar, and convert .042 bar into psi to get .61 psi/x

the absolutely correct answer is 0.609158498 psi/x but .61 is close enough.

POLAND_SPUD wrote:even if there was no link I'd know it's a bot because of female name