Re: [ERPS] Low pressure tanks?

[Ian Woollard]

David Weinshenker wrote: Randall Clague wrote: On Mon, 21 Jul 2003 18:22:57 -0700, Doug Jones <[EMAIL PROTECTED]> wrote: It should be pretty near the original temperature... or slightly below, since the ullage is pressurized by gas which has been expanded through a regulator from higher pressure. Be careful- this is true for nitrogen, but helium can actually get hotter when going through a regulator (helium is usually above its Joule-Thompson inversion temperature, 40 K). OK, I'm sure I'm not the only one here who doesn't follow this. But I'll be the first to admit my ignorance. Huh? Someone will probably have a longer answer, but the short version is: Helium is just weird that way. All the gases are weird that way, mostly not at room temp though (except neon):      He         40 K      N2         621 K      O2         764 K      Ne         231 K See http://www.chem.arizona.edu/~salzmanr/480a/480ants/jadjte/jadjte.html -davew -- -Ian "If you want to build a ship, don't drum up the workers to gather wood, divide the work, and give orders. Instead, teach them to yearn for the vast and endless sea." -Antoine de Saint-Exupery