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arXiv · 1711.02028

Local pressure for confined systems

Paolo Malgaretti·Markus Bier
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Abstract

We derive a general closed expression for the local pressure exerted onto the corrugated walls of a channel confining a fluid medium. When the fluid medium is at equilibrium the local pressure is a functional of the shape of the walls. It is shown that, due to the intrinsic non-local character of the interactions among the particles forming the fluid, the applicability of approximate schemes such as the concept of a surface of tension or morphometric thermodynamics is limited to wall curvatures small compared to the range of particle-particle interactions.

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Paolo Malgaretti, Markus Bier. 2017-11-06. Local pressure for confined systems. https://doi.org/10.1103/physreve.97.022102

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