The Violation of Objectivity in Laplace Formulations of the Navier-Stokes Equations

The Navier–Stokes equations written in Laplace form are often the starting point of many numerical methods for the simulation of viscous flows. Imposing the natural boundary conditions of the Laplace form or neglecting the viscous contributions on free surfaces are traditionally considered reasonabl...

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Detalles Bibliográficos
Autores: Limache, Alejandro Cesar, Idelsohn, Sergio Rodolfo, Rossi, R., Oñate, E.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2007
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/20794
Acceso en línea:http://hdl.handle.net/11336/20794
Access Level:acceso abierto
Palabra clave:Navier-Stokes Equations
Objectivity
Laplace Diffusion Operator
Annular Cavity
https://purl.org/becyt/ford/2.11
https://purl.org/becyt/ford/2
Descripción
Sumario:The Navier–Stokes equations written in Laplace form are often the starting point of many numerical methods for the simulation of viscous flows. Imposing the natural boundary conditions of the Laplace form or neglecting the viscous contributions on free surfaces are traditionally considered reasonable and harmless assumptions. With these boundary conditions any formulation derived from integral methods (like finite elements or finite volumes) recovers the pure Laplacian aspect of the strong form of the equations. This approach has also the advantage of being convenient in terms of computational effort and, as a consequence, it is used extensively. However, we have recently discovered that these resulting Laplacian formulations violate a basic axiom of continuum mechanics: the principle of objectivity. In the present article we give an accurate account about these topics. We also show that unexpected differences may sometimes arise between Laplace discretizations and divergence discretizations.