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arXiv · 2301.02860

Thermodynamical Modeling of Multiphase Flow System with Surface Tension and Flow

Hajime Koba
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Abstract

We consider the governing equations for the motion of the viscous fluids in two moving domains and an evolving surface from both energetic and thermodynamic points of view. We make mathematical models for multiphase flow with surface flow by our energetic variational and thermodynamic approaches. More precisely, we apply our energy densities, the first law of thermodynamics, and the law of conservation of total energy to derive our multiphase flow system with surface tension and flow. We study the conservative forms and conservation laws of our system by using the surface transport theorem and integration by parts. Moreover, we investigate the enthalpy, the entropy, the Helmholtz free energy, and the Gibbs free energy of our model by applying the thermodynamic identity. The key idea of deriving surface tension and viscosities is to make use of both the first law of thermodynamics and our energy densities.

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Hajime Koba. 2023-01-07. Thermodynamical Modeling of Multiphase Flow System with Surface Tension and Flow. https://arxiv.org/abs/2301.02860

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