{ "id": "2301.02077", "version": "v1", "published": "2023-01-05T14:23:24.000Z", "updated": "2023-01-05T14:23:24.000Z", "title": "On the $L^\\infty(0,T;L^2(Ω)^d)$-stability of Discontinuous Galerkin schemes for incompressible flows", "authors": [ "Pablo Alexei Gazca-Orozco", "Alex Kaltenbach" ], "categories": [ "math.NA", "cs.NA" ], "abstract": "The property that the velocity $\\boldsymbol{u}$ belongs to $L^\\infty(0,T;L^2(\\Omega)^d)$ is an essential requirement in the definition of energy solutions of models for incompressible fluids; it is, therefore, highly desirable that the solutions produced by discretisation methods are uniformly stable in the $L^\\infty(0,T;L^2(\\Omega)^d)$-norm. In this work, we establish that this is indeed the case for Discontinuous Galerkin (DG) discretisations (in time and space) of non-Newtonian implicitly constituted models with $p$-structure, in general, assuming that $p\\geq \\frac{3d+2}{d+2}$; the time discretisation is equivalent to a RadauIIA Implicit Runge-Kutta method. To aid in the proof, we derive Gagliardo-Nirenberg-type inequalities on DG spaces, which might be of independent interest", "revisions": [ { "version": "v1", "updated": "2023-01-05T14:23:24.000Z" } ], "analyses": { "keywords": [ "discontinuous galerkin schemes", "incompressible flows", "radauiia implicit runge-kutta method", "essential requirement", "energy solutions" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }