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Updated: Jun 14, 2026

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Inconsistency of a dissipative contribution to the mass flux in hydrodynamics
Hans Christian Ottinger1, Henning Struchtrup, Mario Liu
1Department of Materials, ETH Zürich, HCI H 543, CH-8093 Zürich, Switzerland.
Abstract:
The possibility of dissipative contributions to the mass flux is considered in detail. A general thermodynamically consistent framework is developed to obtain such terms, the compatibility of which with general principles is then checked-including Galilean invariance, the possibility of steady rigid rotation and uniform center-of-mass motion, the existence of a locally conserved angular momentum, and material objectivity. All previously discussed scenarios of dissipative mass fluxes are found to be ruled out by some combinations of these principles but not a new one that includes a smoothed velocity field v[over ] . However, this field v[over ] is nonlocal and leads to unacceptable consequences in specific situations. Hence, we can state with confidence that a dissipative contribution to the mass flux is not possible.
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