Abstract

Mixed finite elements play a central role in many important CFD applications involving Stokes solvers and alike. A natural mixed finite element for the Stokes equations is the Qk-Qk−1 element on rectangular grids, by which the velocity is approximated by continuous polynomials of separated degree k and the pressure is approximated by discontinuous polynomials of separated degree k−1. Such an element is, however, not stable. We propose in this paper three modified Qk-Qk−1 elements with certain element-wise divergence-free property of velocity, where the pressure space is slightly restricted to subspaces in C−1-Qk−1, yet the optimal order of approximation is still retained. The stability and approximation analysis for the new elements are presented. Comprehensive numerical experiments are also conducted to confirm the theoretical analysis and to reveal the super-convergence for some of these new elements.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.