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arXiv · 2203.04069

Construction of Boundary Conditions for Hyperbolic Relaxation Approximations II: Jin-Xin Relaxation Model

Xiaxia Cao·Wen-An Yong
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Abstract

This is our second work in the series about constructing boundary conditions for hyperbolic relaxation approximations. The present work is concerned with the one-dimensional linearized Jin-Xin relaxation model, a convenient approximation of hyperbolic conservation laws, with non-characteristic boundaries. Assume that proper boundary conditions are given for the conservation laws. We construct boundary conditions for the relaxation model with the expectation that the resultant initial-boundary-value problems are approximations to the given conservation laws with the boundary conditions. The constructed boundary conditions are highly non-unique. Their satisfaction of the generalized Kreiss condition is analyzed. The compatibility with initial data is studied. Furthermore, by resorting to a formal asymptotic expansion, we prove the effectiveness of the approximations.

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Xiaxia Cao, Wen-An Yong. 2022-03-08. Construction of Boundary Conditions for Hyperbolic Relaxation Approximations II: Jin-Xin Relaxation Model. https://arxiv.org/abs/2203.04069

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