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arXiv · 1810.10616

Approximate continuous data assimilation of the 2D Navier-Stokes equations via the Voigt-regularization with observable data

Abstract

We propose a data assimilation algorithm for the 2D Navier-Stokes equations, based on the Azouani, Olson, and Titi (AOT) algorithm, but applied to the 2D Navier-Stokes-Voigt equations. Adapting the AOT algorithm to regularized versions of Navier-Stokes has been done before, but the innovation of this work is to drive the assimilation equation with observational data, rather than data from a regularized system. We first prove that this new system is globally well-posed. Moreover, we prove that for any admissible initial data, the $L^2$ and $H^1$ norms of error are bounded by a constant times a power of the Voigt-regularization parameter $α>0$, plus a term which decays exponentially fast in time. In particular, the large-time error goes to zero algebraically as $α$ goes to zero. Assuming more smoothness on the initial data and forcing, we also prove similar results for the $H^2$ norm.

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BibTeXRIS

Adam Larios, Yuan Pei. 2018-10-24. Approximate continuous data assimilation of the 2D Navier-Stokes equations via the Voigt-regularization with observable data. https://arxiv.org/abs/1810.10616

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