{ "id": "2012.15582", "version": "v1", "published": "2020-12-31T12:36:16.000Z", "updated": "2020-12-31T12:36:16.000Z", "title": "Isogeometric discretizations of the Stokes problem on trimmed geometries", "authors": [ "Riccardo Puppi" ], "categories": [ "math.NA", "cs.NA" ], "abstract": "The isogeometric approximation of the Stokes problem in a trimmed domain is studied. This setting is characterized by an underlying mesh unfitted with the boundary of the physical domain making the imposition of the essential boundary conditions a challenging problem. A very popular strategy is to rely on the so-called Nitsche method [22]. We show with numerically examples that in some degenerate trimmed domain configurations there is a lack of stability of the formulation, potentially polluting the computed solutions. After extending the stabilization procedure of [17] to incompressible flow problems, we theoretically prove that, combined with the Raviart-Thomas isogeometric element, we are able to recover the well-posedness of the formulation and, consequently, optimal a priori error estimates. Numerical results corroborating the theory and extending it for the case of the isogeometric N\\'ed\\'elec and Taylor-Hood elements are provided.", "revisions": [ { "version": "v1", "updated": "2020-12-31T12:36:16.000Z" } ], "analyses": { "keywords": [ "stokes problem", "isogeometric discretizations", "trimmed geometries", "priori error estimates", "essential boundary conditions" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }