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T. Loimer:
"The thermodynamic states of a fluid in a Joule-Thomson process involving phase changes at interfaces with large curvature";
Poster: 12th Joint European Thermodynamics Conference, Brescia; 2013-07-01 - 2013-07-05; in: "Proceedings of the 12th Joint European Thermodynamics Conference", M. Pilotelli, G. P. Beretta (ed.); Snoopy, (2013), ISBN: 978-88-89252-22-2; 537 - 541.

In the classical experiment of Joule and Thomson, a gas passes through a porous plug. The pressure difference between the upstream and the downstream side of the porous plug causes a temperature difference. Here, the flow process is described for the case that the fluid may condense, and the pressure loss is caused by a thin capillary. The process is calculated assuming local thermodynamic equilibrium and one-dimensional temperature and pressure distributions, respectively.

A vapor far from saturation does not condense, and the temperature and pressure distribution for the common Joule-Thomson process is recovered. A vapor close enough to saturation may condense partially or completely, and a liquid or a two-phase mixture flows through a part of the capillary. The thermodynamic path of the fluid is presented in temperature-entropy and pressure-temperature diagrams.