@article {DANCHIN2011253, title = {The well-posedness issue for the density-dependent Euler equations in endpoint Besov spaces}, journal = {Journal de Math{\'e}matiques Pures et Appliqu{\'e}es}, volume = {96}, number = {3}, year = {2011}, pages = {253 - 278}, abstract = {

This work is the continuation of the recent paper (Danchin, 2010) [9] devoted to the density-dependent incompressible Euler equations. Here we concentrate on the well-posedness issue in Besov spaces of type B$\infty$,rs embedded in the set of Lipschitz continuous functions, a functional framework which contains the particular case of H{\"o}lder spaces C1,α and of the endpoint Besov space B$\infty$,11. For such data and under the non-vacuum assumption, we establish the local well-posedness and a continuation criterion in the spirit of that of Beale, Kato and Majda (1984) [2]. In the last part of the paper, we give lower bounds for the lifespan of a solution. In dimension two, we point out that the lifespan tends to infinity when the initial density tends to be a constant. This is, to our knowledge, the first result of this kind for the density-dependent incompressible Euler equations. R{\'e}sum{\'e} Ce travail compl{\`e}te l'article r{\'e}cent (Danchin, 2010) [9] consacr{\'e} au syst{\`e}me d'Euler incompressible {\`a} densit{\'e} variable. Lorsque l'{\'e}tat initial ne comporte pas de vide, on montre ici que le syst{\`e}me est bien pos{\'e} dans tous les espaces de Besov B$\infty$,rs inclus dans l'ensemble des fonctions lipschitziennes. Ce cadre fonctionnel contient en particulier les espaces de H{\"o}lder C1,α et l'espace de Besov limite B$\infty$,11. On {\'e}tablit {\'e}galement un crit{\`e}re de prolongement dans l'esprit de celui de Beale, Kato et Majda (1984) [2] pour le cas homog{\`e}ne. Dans la derni{\`e}re partie de l'article, on donne des minorations pour le temps de vie des solutions du syst{\`e}me. En dimension deux, on montre que ce temps de vie tend vers l'infini lorsque la densit{\'e} tend {\`a} {\^e}tre homog{\`e}ne. {\`A} notre connaissance, il s'agit du premier r{\'e}sultat de ce type pour le syst{\`e}me d'Euler incompressible {\`a} densit{\'e} variable.

}, keywords = {Blow-up criterion, Critical regularity, Incompressible Euler equations, Lifespan, Nonhomogeneous inviscid fluids}, issn = {0021-7824}, doi = {https://doi.org/10.1016/j.matpur.2011.04.005}, url = {http://www.sciencedirect.com/science/article/pii/S0021782411000511}, author = {Rapha{\"e}l Danchin and Francesco Fanelli} }