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DOE OSTI · 1972117

Comparison of two pressure–temperature equilibration methods

Subramanian, Gopinath Santhana Ganapathy·Leiding, Jeffery Allen
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Abstract

We compare and contrast the traditionally used method of solving the pressure–temperature equilibration problem in hydrodynamics, where specific internal energy and density are considered independent variables, with a different method where pressure and temperature are independent variables. With the goal of examining the robustness of the two methods as the number of components increases, we examine 2-, 4-, 6-, and 8-component systems. After equilibrating more than 10 4 initial conditions for each system using both methods, we demonstrate that the latter method constrains the search space by lowering its dimensionality and forces a better initial guess, resulting in a higher probability of convergence to solution with fewer, cheaper iterations.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSNewton Raphson methodNewtonian mechanicschemical kinetics and dynamicsexplosiveshydrodynamicsiteration methodlaws of thermodynamicsmultivariable calculustheoretical computer sciencethermodynamic states and processes

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Subramanian, Gopinath Santhana Ganapathy, Leiding, Jeffery Allen. 2023-02-23. Comparison of two pressure–temperature equilibration methods. https://doi.org/10.1063/5.0132588

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