TY - UNPD A1 - Fengler, Martin J. A1 - Freeden, Willi T1 - A Nonlinear Galerkin Scheme Involving Vector and Tensor Spherical Harmonics for Solving the Incompressible Navier-Stokes Equation on the Sphere N2 - This work is concerned with a nonlinear Galerkin method for solving the incompressible Navier-Stokes equation on the sphere. It extends the work of Debussche, Marion,Shen, Temam et al. from one-dimensional or toroidal domains to the spherical geometry. In the first part, the method based on type 3 vector spherical harmonics is introduced and convergence is indicated. Further it is shown that the occurring coupling terms involving three vector spherical harmonics can be expressed algebraically in terms of Wigner-3j coefficients. To improve the numerical efficiency and economy we introduce an FFT based pseudo spectral algorithm for computing the Fourier coefficients of the nonlinear advection term. The resulting method scales with O(N^3), if N denotes the maximal spherical harmonic degree. The latter is demonstrated in an extensive numerical example. T3 - Schriften zur Funktionalanalysis und Geomathematik - 11 KW - Navier-Stokes-Gleichung KW - Galerkin-Methode KW - Kugelflächenfunktion KW - Schnelle Fourier-Transformation KW - Globale nichtlineare Analysis KW - Kugel KW - Nichtlineares Galerkinverfahren KW - Inkompressibel Navier-Stokes KW - Incompressible Navier-Stokes KW - Nonlinear Galerkin Method KW - Vector Spherical Harmonics KW - Tensor Spherical Harmonics KW - Fast Pseudo Spectral Algorithm Y1 - 2004 UR - https://kluedo.ub.uni-kl.de/frontdoor/index/index/docId/1561 UR - https://nbn-resolving.org/urn:nbn:de:hbz:386-kluedo-13450 ER -