Large-Time Behavior of Solutions in the Critical Spaces for the Non-isentropic Compressible Navier–Stokes Equations with Capillarity

In this paper, we investigate the large-time behavior for the non-isentropic compressible Navier–Stokes equations with capillarity in the whole space Rd\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\mathbb {R}}^{d}$$\end{document} (d≥3\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$d\ge 3$$\end{document}). Under an additional smallness assumption of the low frequencies of initial data, the time-decay estimates of Lq\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$L^{q}$$\end{document}–Lr\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$L^{r}$$\end{document} type for global strong solutions near constant equilibrium (away from vacuum) can be deduced by establishing the time-weighted energy inequality. On the other hand, a pure energy approach (without the spectral analysis) different from the time-weighted energy method is performed, which allows us not only to get the time-decay rates but also to remove the smallness condition of low frequencies of initial data. The treatment of new nonlinear terms arising from capillary mainly depends on non classical Besov product estimates and the refined use of Sobolev embeddings and interpolations.