Throttling Process

ahmad.hasan

dear all

What is the throttling Process?
what is Joule homson Effect?

FredGarvin

Google is your friend.

http://en.wikipedia.org/wiki/Joule-Thomson_effect
http://www.answers.com/topic/joule-thomson-effect
http://www.chm.wright.edu/grossie/chm457/3_2_06.pdf
http://www.madsci.org/posts/archives...3920.Eg.r.html
http://www.mmr.com/jt.htm

Cyrus

A throttling process is a process that is isenthalpic. Thus, [tex] h_1 = h_2 [/tex]. This means that the following is also true, [tex] u_1 + P_1 v_1 = u_2 + P_2 v_2 [/tex]. So if you drop pressure in a throttling value, you increase the internal energy, and vise versa.

The Joule -thomson- effect deals with the fact that as you expand a gas it looses temperature. Note that for hydrogen; however, it gains temperaturee as it expands. This makes hyrdogen particularly dagnerous.

ahmad.hasan

Pressure drops in CNG kit Pressure regulator from 300 bar to 4 bar in 1st chamber due to expansion is it throttling process? temperature also drops in it.

Cyrus

Yes, that is exactly what it is.

Edit: wait, what do you mean by expansion? Is it going through a nozzle?

ahmad.hasan

no it is going throug valve (sloninoid valve) from storage cylinder through high pressure pipe into solinoid valve and then in the 1st stage chamber of pressure regulator.

Cyrus

Yes, it is a throttling valve.

ahmad.hasan

what is the value of joule-thomson coefficient for methane