{ "id": "2207.06808", "version": "v1", "published": "2022-07-14T10:37:10.000Z", "updated": "2022-07-14T10:37:10.000Z", "title": "Reduced-order Galerkin models of plane Couette flow", "authors": [ "André V. G. Cavalieri", "Petrônio A. S. Nogueira" ], "comment": "10 pages, 4 figures", "categories": [ "physics.flu-dyn" ], "abstract": "Reduced-order models were derived for plane Couette flow using Galerkin projection, with orthonormal basis functions taken as the leading controllability modes of the linearised Navier-Stokes system for a few low wavenumbers. Resulting Galerkin systems comprise ordinary differential equations, with a number of degrees of freedom ranging from 144 to 600, which may be integrated to large times without sign of numerical instability. The reduced-order models so obtained are also found to match statistics of direct numerical simulations at Reynolds number 500 and 1200 with reasonable accuracy, despite a truncation of orders of magnitude in the degrees of freedom of the system. The present models offer thus an interesting compromise between simplicity and accuracy in a canonical wall-bounded flow, with relatively few modes representing coherent structures in the flow and their dominant dynamics.", "revisions": [ { "version": "v1", "updated": "2022-07-14T10:37:10.000Z" } ], "analyses": { "keywords": [ "plane couette flow", "reduced-order galerkin models", "galerkin systems comprise ordinary differential", "systems comprise ordinary differential equations" ], "note": { "typesetting": "TeX", "pages": 10, "language": "en", "license": "arXiv", "status": "editable" } } }