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arXiv · 2204.05135

Exergetic Port-Hamiltonian Systems: Navier-Stokes-Fourier Fluid

Markus Lohmayer·Sigrid Leyendecker
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Abstract

The Exergetic Port-Hamiltonian Systems modeling language combines a graphical syntax inspired by bond graphs with a port-Hamiltonian semantics akin to the GENERIC formalism. The syntax enables the modular and hierarchical specification of the composition pattern of lumped and distributed-parameter models. The semantics reflects the first and second law of thermodynamics as structural properties. Interconnected and hierarchically defined models of multiphysical thermodynamic systems can thus be expressed in a formal language accessible to humans and computers alike. We discuss a composed model of the Navier-Stokes-Fourier fluid on a fixed spatial domain as an example of an open distributed-parameter system. At the top level, the system comprises five subsystems which model kinetic energy storage, internal energy storage, thermal conduction, bulk viscosity, and shear viscosity.

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Markus Lohmayer, Sigrid Leyendecker. 2022-04-01. Exergetic Port-Hamiltonian Systems: Navier-Stokes-Fourier Fluid. https://arxiv.org/abs/2204.05135

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