# Homework Help: Air throttling (real gas)

1. Mar 19, 2009

### kandelabr

1. The problem statement, all variables and given/known data
I need to know what happens if compressed air from a vessel at room temperature is throttled from 450 bar to 2 bar.

2. Relevant equations
I know Joule-Thomson effect (http://http://en.wikipedia.org/wiki/Joule-Thomson_effect" [Broken]) deals with this, but I'd need it explained a bit more clearly, like what volume is in the equation and under what circumstances is it true.

3. The attempt at a solution
I know air will cool down when throttled, but at certain pressure and temperature it will liquefy. Will it liquefy during throttling?
What about work that was lost due to entropy change? If this system is isothermal, that is, the throttled air is reheated to initial temperature, ...
d0h, there's too many things in my head. I hope you know what I don't know I don't know.
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

Last edited by a moderator: May 4, 2017