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arXiv · 2209.12311

A fully-discrete virtual element method for the nonstationary Boussinesq equations

L. Beirão da Veiga·D. Mora·A. Silgado
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Abstract

In the present work we propose and analyze a fully coupled virtual element method of high order for solving the two dimensional nonstationary Boussinesq system in terms of the stream-function and temperature fields. The discretization for the spatial variables is based on the coupling $C^1$- and $C^0$-conforming virtual element approaches, while a backward Euler scheme is employed for the temporal variable. Well-posedness and unconditional stability of the fully-discrete problem is provided. Moreover, error estimates in $H^2$- and $H^1$-norms are derived for the stream-function and temperature, respectively. Finally, a set of benchmark tests are reported to confirm the theoretical error bounds and illustrate the behavior of the fully-discrete scheme.

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L. Beirão da Veiga, D. Mora, A. Silgado. 2022-09-25. A fully-discrete virtual element method for the nonstationary Boussinesq equations. https://doi.org/10.1016/j.cma.2023.115947

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