A Discontinuous Velocity Least Squares Finite Element Method for the Stokes Equations with Improved Mass Conservation
نویسندگان
چکیده
Conventional least squares finite element methods (LSFEM) for incompressible flows conserve mass approximately. In some cases, this can lead to an unacceptable loss of mass and unphysical solutions. In this report we formulate a new, locally conservative LSFEM for the Stokes equations which computes a discrete velocity field that is point-wise divergence free on each element. To this end, we employ discontinuous velocity approximations which are defined by using a local stream-function on each element. The effectiveness of the new LSFEM approach on improved local and global mass conservation is compared with a conventional LSFEM employing standard C0 Lagrangian elements.
منابع مشابه
A locally conservative, discontinuous least-squares finite element method for the Stokes equations
Conventional least-squares finite element methods (LSFEMs) for incompressible flows conserve mass only approximately. For some problems, mass loss levels are large and result in unphysical solutions. In this paper we formulate a new, locally conservative LSFEM for the Stokes equations wherein a discrete velocity field is computed that is point-wise divergence free on each element. The central i...
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