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arXiv · 1411.7074

Optimal first-order error estimates of a fully segregation scheme for the Navier-Stokes equations

F. Guillén-González·M. V. Redondo-Neble
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Abstract

A first-order linear fully discrete scheme is studied for the incompressible time-dependent Navier-Stokes equations in three-dimensional domains. This scheme, based on an incremental pressure projection method, decouples each component of the velocity and the pressure, solving in each time step, a linear convection-diffusion problem for each component of the velocity and a Poisson-Neumann problem for the pressure. Using first-order \emph{inf-sup} stable $C^0$-finite elements, optimal error estimates of order $O(k+h)$ are deduced without imposing constraints on $h$ and $k$, the mesh size and the time step, respectively. Finally, some numerical results are presented according the theoretical analysis, and also comparing to other current first-order segregated schemes.

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F. Guillén-González, M. V. Redondo-Neble. 2014-11-26. Optimal first-order error estimates of a fully segregation scheme for the Navier-Stokes equations. https://arxiv.org/abs/1411.7074

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