{ "id": "2010.13935", "version": "v1", "published": "2020-10-26T22:45:39.000Z", "updated": "2020-10-26T22:45:39.000Z", "title": "A discretize-then-map approach for the treatment of parameterized geometries in model order reduction", "authors": [ "Tommaso Taddei", "Lei Zhang" ], "categories": [ "math.NA", "cs.NA" ], "abstract": "We propose a new general approach for the treatment of parameterized geometries in projection-based model order reduction. During the offline stage, given (i) a family of parameterized domains $\\{ \\Omega_{\\mu}: \\mu \\in \\mathcal{P} \\} \\subset \\mathbb{R}^D$ where $\\mu \\in \\mathcal{P} \\subset \\mathbb{R}^P$ denotes a vector of parameters, (ii) a parameterized mapping $\\underline{\\Phi}_{\\mu}$ between a reference domain $\\Omega$ and the parameter-dependent domain $\\Omega_{\\mu}$, and (iii) a finite element triangulation of $\\Omega$, we resort to an empirical quadrature procedure to select a subset of the elements of the grid. During the online stage, we first use the mapping to \"move\" the nodes of the selected elements and then we use standard element-wise residual evaluation routines to evaluate the residual and possibly its Jacobian. We discuss how to devise an online-efficient reduced-order model and we discuss the differences with the more standard \"map-then-discretize\" approach (e.g., Rozza, Huynh, Patera, ACME, 2007); in particular, we show how the discretize-then-map framework greatly simplifies the implementation of the reduced-order model. We apply our approach to a two-dimensional potential flow problem past a parameterized airfoil, and to the two-dimensional RANS simulations of the flow past the Ahmed body.", "revisions": [ { "version": "v1", "updated": "2020-10-26T22:45:39.000Z" } ], "analyses": { "subjects": [ "65N30", "41A45", "35J57" ], "keywords": [ "model order reduction", "parameterized geometries", "discretize-then-map approach", "two-dimensional potential flow problem past", "reduced-order model" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }