Least-squares spectral element solution of incompressible Navier-Stokes equations with adaptive refinement

2012-05-01
Ozcelikkale, Altug
Sert, Cüneyt
Least-squares spectral element solution of steady, two-dimensional, incompressible flows are obtained by approximating velocity, pressure and vorticity variable set on GaussLobatto-Legendre nodes. Constrained Approximation Method is used for h- and p-type nonconforming interfaces of quadrilateral elements. Adaptive solutions are obtained using a posteriori error estimates based on least squares functional and spectral coefficient. Effective use of p-refinement to overcome poor mass conservation drawback of leastsquares formulation and successful use of h- and p-refinement together to solve problems with geometric singularities are demonstrated. Capabilities and limitations of the developed code are presented using Kovasznay flow, flow past a circular cylinder in a channel and backward facing step flow.
JOURNAL OF COMPUTATIONAL PHYSICS

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Citation Formats
A. Ozcelikkale and C. Sert, “Least-squares spectral element solution of incompressible Navier-Stokes equations with adaptive refinement,” JOURNAL OF COMPUTATIONAL PHYSICS, pp. 3755–3769, 2012, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/46272.