In this paper we present a new spectral method for the fast evaluation of the Fokker-Planck-Landau collision operator. The method allows to obtain spectrally accurate numerical solutions with simply O(n log 2 n) operations in contrast with the usual O(n 2 ) cost of a deterministic scheme. We show that the method preserves the total mass whereas momentum and energy are approximated with spectral accuracy. Numerical results for both the Maxwellian and the Coulombian case in 2D and 3D velocity space are also given. Key words: Fokker-Planck-Landau equation, spectral methods, fast Fourier transform. 1 Introduction. This paper is devoted to the development of numerical schemes for the accurate computation of the solution of the Fokker-Planck-Landau equation.
Fast spectral methods for the Fokker-Planck-Landau equation
PARESCHI, Lorenzo;
2000
Abstract
In this paper we present a new spectral method for the fast evaluation of the Fokker-Planck-Landau collision operator. The method allows to obtain spectrally accurate numerical solutions with simply O(n log 2 n) operations in contrast with the usual O(n 2 ) cost of a deterministic scheme. We show that the method preserves the total mass whereas momentum and energy are approximated with spectral accuracy. Numerical results for both the Maxwellian and the Coulombian case in 2D and 3D velocity space are also given. Key words: Fokker-Planck-Landau equation, spectral methods, fast Fourier transform. 1 Introduction. This paper is devoted to the development of numerical schemes for the accurate computation of the solution of the Fokker-Planck-Landau equation.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.