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Title: Shock dynamics of phase diagrams

A thermodynamic phase transition denotes a drastic change of state of a physical system due to a continuous change of thermodynamic variables, as for instance pressure and temperature. The classical van der Waals equation of state is the simplest model that predicts the occurrence of a critical point associated with the gas–liquid phase transition. Nevertheless, below the critical temperature theoretical predictions of the van der Waals theory significantly depart from the observed physical behaviour. We develop a novel approach to classical thermodynamics based on the solution of Maxwell relations for a generalised family of nonlocal entropy functions. This theory provides an exact mathematical description of discontinuities of the order parameter within the phase transition region, it explains the universal form of the equations of state and the occurrence of triple points in terms of the dynamics of nonlinear shock wave fronts. -- Highlights: •A new generalisation of van der Waals equation of state. •Description of phase transitions in terms of shock dynamics of state curves. •Proof of the universality of equations of state for a general class of models. •Interpretation of triple points as confluence of classical shock waves. •Correspondence table between thermodynamics and nonlinear conservation laws.
Authors:
Publication Date:
OSTI Identifier:
22314786
Resource Type:
Journal Article
Resource Relation:
Journal Name: Annals of Physics (New York); Journal Volume: 343; Journal Issue: Complete; Other Information: Copyright (c) 2014 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CONSERVATION LAWS; CRITICAL TEMPERATURE; ENTROPY; EQUATIONS OF STATE; MATHEMATICAL SOLUTIONS; NONLINEAR PROBLEMS; ORDER PARAMETERS; PARTIAL DIFFERENTIAL EQUATIONS; PHASE DIAGRAMS; PHASE TRANSFORMATIONS; PRESSURE DEPENDENCE; SHOCK WAVES; TEMPERATURE DEPENDENCE; THERMODYNAMICS; TRIPLE POINT; VAN DER WAALS FORCES