Well-posedness analysis of multicomponent incompressible flow models

Dieter Bothe; Pierre-Etienne Druet

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arXiv · 2005.12052

Well-posedness analysis of multicomponent incompressible flow models

Dieter Bothe·Pierre-Etienne Druet

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Abstract

In this paper, we extend our study of mass transport in multicomponent isothermal fluids to the incompressible case. For a mixture, incompressibility is defined as the independence of average volume on pressure, and a weighted sum of the partial mass densities stays constant. In this type of models, the velocity field in the Navier-Stokes equations is not solenoidal and, due to different specific volumes of the species, the pressure remains connected to the densities by algebraic formula. By means of a change of variables in the transport problem, we equivalently reformulate the PDE system as to eliminate positivity and incompressibility constraints affecting the density, and prove two type of results: the local-in-time well-posedness in classes of strong solutions, and the global-in-time existence of solutions for initial data sufficiently close to a smooth equilibrium solution.

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Dieter Bothe, Pierre-Etienne Druet. 2020-05-25. Well-posedness analysis of multicomponent incompressible flow models. https://arxiv.org/abs/2005.12052

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