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arXiv · 1801.06391

Decoupling schemes for predicting compressible fluid flows

Abstract

Numerical simulation of compressible fluid flows is performed using the Euler equations. They include the scalar advection equation for the density, the vector advection equation for the velocity and a given pressure dependence on the density. An approximate solution of an initial--boundary value problem is calculated using the finite element approximation in space. The fully implicit two-level scheme is used for discretization in time. Numerical implementation is based on Newton's method. The main attention is paid to fulfilling conservation laws for the mass and total mechanical energy for the discrete formulation. Two-level schemes of splitting by physical processes are employed for numerical solving problems of barotropic fluid flows. For a transition from one time level to the next one, an iterative process is used, where at each iteration the linearized scheme is implemented via solving individual problems for the density and velocity. Possibilities of the proposed schemes are illustrated by numerical results for a two--dimensional model problem with density perturbations.

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BibTeXRIS

Petr N. Vabishchevich. 2018-01-19. Decoupling schemes for predicting compressible fluid flows. https://arxiv.org/abs/1801.06391

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