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arXiv · 2007.06607

Analysis of a thermodynamically consistent Navier--Stokes--Cahn--Hilliard model

Robert Lasarzik
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Abstract

In this paper, existence of generalized solutions to a thermodynamically consistent Navier--Stokes--Cahn--Hilliard model introduced in [18] is proven in any space dimension. The generalized solvability concepts are measure-valued and dissipative solutions. The measure-valued formulation incorporates an entropy inequality and an energy inequality instead of an energy balance in a nowadays standard way, the Gradient flow of the internal variable is fulfilled in a weak and the momentum balance in a measure-valued sense. In the dissipative formulation, the distributional relations of the momentum balance and the energy as well as entropy inequality are replaced by a relative energy inequality. Additionally, we prove the weak-strong uniqueness of the proposed solution concepts and that all generalized solutions with additional regularity are indeed strong solutions.

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Robert Lasarzik. 2020-07-13. Analysis of a thermodynamically consistent Navier--Stokes--Cahn--Hilliard model. https://doi.org/10.1016/j.na.2021.112526

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