A standard method for proving the inf-sup condition implying stability of finite element approximations for the stationary Stokes equations is to construct a Fortin operator. In this paper, we show how this can be done for two-dimensional triangular and rectangular Taylor-Hood methods, which use continuous piecewise polynomial approximations for both velocity and pressure.
@article{M2AN_2008__42_3_411_0, author = {Falk, Richard S.}, title = {A Fortin operator for two-dimensional Taylor-Hood elements}, journal = {ESAIM: Mathematical Modelling and Numerical Analysis - Mod\'elisation Math\'ematique et Analyse Num\'erique}, volume = {42}, year = {2008}, pages = {411-424}, doi = {10.1051/m2an:2008008}, mrnumber = {2423792}, zbl = {1143.65085}, language = {en}, url = {http://dml.mathdoc.fr/item/M2AN_2008__42_3_411_0} }
Falk, Richard S. A Fortin operator for two-dimensional Taylor-Hood elements. ESAIM: Mathematical Modelling and Numerical Analysis - Modélisation Mathématique et Analyse Numérique, Tome 42 (2008) pp. 411-424. doi : 10.1051/m2an:2008008. http://gdmltest.u-ga.fr/item/M2AN_2008__42_3_411_0/
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