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Updated: Jun 4, 2025

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Contrasting thermodynamic and hydrodynamic entropy
Mahendra K Verma1, Rodion Stepanov2,3, Alexandre Delache4,5
1Department of Physics, <a href="https://ror.org/05pjsgx75">Indian Institute of Technology Kanpur</a>, Kanpur 208016, India.
Abstract:
In this paper, using hydrodynamic entropy, we quantify multiscale disorder in Euler and hydrodynamic turbulence. These examples illustrate that the hydrodynamic entropy is not extensive because it is not proportional to the system size. Consequently, we cannot add hydrodynamic and thermodynamic entropies, which measure disorder at macroscopic and microscopic scales, respectively. In this paper, we also discuss the hydrodynamic entropy for the time-dependent Ginzburg-Landau equation and Ising spins.
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