TY - JOUR T1 - Hexagonal Fourier-Galerkin Methods for the Two-Dimensional Homogeneous Isotropic Decaying Turbulence AU - Li , Huiyuan JO - Journal of Mathematical Study VL - 1 SP - 21 EP - 46 PY - 2014 DA - 2014/03 SN - 47 DO - http://doi.org/10.4208/jms.v47n1.14.02 UR - https://global-sci.org/intro/article_detail/jms/9948.html KW - Fourier-Galerkin methods, hexagonal lattices, homogeneous isotropic turbulence, direct numerical simulation. AB -
In this paper, we propose two hexagonal Fourier-Galerkin methods for the direct numerical simulation of the two-dimensional homogeneous isotropic decaying turbulence. We first establish the lattice Fourier analysis as a mathematical foundation. Then a universal approximation scheme is devised for our hexagonal Fourier-Galerkin methods for Navier-Stokes equations. Numerical experiments mainly concentrate on the decaying properties and the self-similar spectra of the two-dimensional homogeneous turbulence at various initial Reynolds numbers with an initial flow field governed by a Gaussian-distributed energy spectrum. Numerical results demonstrate that both the hexagonal Fourier-Galerkin methods are as efficient as the classic square Fourier-Galerkin method, while provide more effective statistical physical quantities in general.