Joule-Thomson Expansion and the Maxwell Relations

Control console

Set the inlet temperature and pressure, throttle to the outlet pressure and read the temperature difference.

Gas

Inlet temperature

Inlet pressure

MPa

Outlet pressure

MPa

pwrmeasfault

Select the gas and set the thermostat.
For a fixed inlet pressure, record the temperature drop for a series of outlet pressures.
Plot the temperature change against the pressure drop and take the gradient in the limit of small drop; this is the Joule-Thomson coefficient.
Repeat for at least four gases at room temperature, and note the sign in each case.

standby

No readings on this channel yet. Set the controls and press Throttle.

A fresh page. Take your first reading and it will be entered here.

Take at least one reading to plot.