eddy simulation of incompressible flows by using high order methods. .... and of the Gaussian filter; right: 1D non-periodic case, eigenvalues of the Cheby- ... Table 1. Table 1 lists the values of max(-Ði), i.e. of the spectral radius of the Cheby-.
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Fourier approximation : spectra of G
1
0.6
hD h^2 D^2
2
0.4
1 Imaginary part
Spectrum
Eigenvalues of h D and h^2 D^2, N=61
3
Gaussian alpha=1.559 alpha=2 alpha=2.205
0.8
0.2 0 -0.2
0
-1
-0.4 -0.6
-2
-0.8 -1
0
5
10
15 Wavenumber (k)
20
25
-3 -10
30
-9
-8
-7
-6
-5 -4 real part
-3
-2
-1
0
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