Quadratic Velocity/linear Pressure Stokes Elements*
نویسندگان
چکیده
We study the finite element approximation of the stationary Stokes equations in the velocitypressure formulation using continuous piecewise quadratic functions for velocity and discontinuous piecewise linear functions for pressure. For some meshes this method is unstable, even after spurious pressure modes are removed. For other meshes there are spurious local pressure modes, but once they are removed the method is stable, and in particular, the velocity converges with optimal order. On yet other meshes there are no spurious pressure modes and the method is stable and optimally convergent for both pressure and velocity.
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