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arXiv · 1003.4921

Large time decay and growth for solutions of a viscous Boussinesq system

Lorenzo Brandolese·Maria Elena Schonbek
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Abstract

In this paper we analyze the decay and the growth for large time of weak and strong solutions to the three-dimensional viscous Boussinesq system. We show that generic solutions blow up as $t\to\infty$ in the sense that the energy and the $L^p$-norms of the velocity field grow to infinity for large time, for $1\le p<3$. In the case of strong solutions we provide sharp estimates both from above and from below and explicit asymptotic profiles. We also show that solutions arising from $(u_0,θ_0)$ with zero-mean for the initial temperature $θ_0$ have a special behavior as $|x|$ or $t$ tends to infinity: contrarily to the generic case, their energy dissipates to zero for large time.

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Lorenzo Brandolese, Maria Elena Schonbek. 2010-07-28. Large time decay and growth for solutions of a viscous Boussinesq system. https://arxiv.org/abs/1003.4921

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