Mailing List Archive Mailing List Archive
Experienced tri-mix home brewers on the List: I'm considering blending some helium and EAN36 to yield a specific tri-mix (this would be my first attempt at blending tri-mix), and I'd like some guidance regarding fudge factors to use in order to compensate for helium compressibility. My ideal gas calculations would have me first half-fill an "empty" cylinder with helium and then top off with EAN36, to obtain a tri-mix consisting of 18% O2, 50% He, and 32% N2. (At MOD = 225 fsw, this mix has PO2 = 1.41 ata, END = 71.5 ata, and AED = 96 fsw.) Now, my admittedly naive understanding of helium compressibility suggests that I really need to start with more than half-filling the cylinder with helium to obtain the desired mix. My question is: How much more? Specifically, if I'm using twin LP 112's with an ending pressure of 2640 psig, what fudge factor should I use to end up with tri-mix 18/50? Same question if, instead, ending pressure is 3500 psig? Thanks in advance for your suggestions. Ronald -- Send mail for the `techdiver' mailing list to `techdiver@aquanaut.com'. Send subscribe/unsubscribe requests to `techdiver-request@aquanaut.com'.
Navigate by Author:
[Previous]
[Next]
[Author Search Index]
Navigate by Subject:
[Previous]
[Next]
[Subject Search Index]
[Send Reply] [Send Message with New Topic]
[Search Selection] [Mailing List Home] [Home]