The rate of change of temperature with respect to pressure
in a throttling process:
\epsilon_{JT} = \left( \frac{\partial T}{\partial P} \right)_{H} = \frac{\alpha_V \cdot T - 1}{c_{vp}} |
where
| Temperature | |
| Thermal expansion coefficient | |
| Isobaric volumetric heat capacity |
For the Ideal Gas: and Joule–Thomson coefficient is strictly zero:
.
In case of general Fluid: and the temperature
where
is called Inversion Temperature.
The Fluid above Inversion Temperature has negative Joule–Thomson coefficient
and hence will be cooling under expansion (
).
The Fluid below Inversion Temperature has positive Joule–Thomson coefficient
and hence will be warming under expansion (
).
Physics / Thermodynamics / Thermodynamic process / Throttling Temperature Effect