Numerical Analysis and Scientific Computing Preprint Seria Inf-sup stability of geometrically unfitted Stokes finite elements
نویسندگان
چکیده
The paper shows an inf-sup stability property for several well-known 2D and 3D Stokes elements on triangulations which are not fitted to a given smooth or polygonal domain. The property implies stability and optimal error estimates for a class of unfitted finite element methods for the Stokes and Stokes interface problems, such as Nitsche-XFEM or cutFEM. The error analysis is presented for the Stokes problem. All assumptions made in the paper are satisfied once the background mesh is shape-regular and fine enough. XFEM, cutFEM, Stokes problem, LBB condition, finite elements [2010]65N30, 65N12, 76D07, 65N85
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