Enstrophy 8 Anisotropy 4 Arnold's theorem 4 Axisymmetric flow 4 Basic flow 4 Beltrami 4 Beltrami flow 4 Complex topology 4 Decay (organic) 4 Decay law 4 Eigen-value 4 Eigenvalues and eigenfunctions 4 Energy decay 4 Energy spectra 4 Euler flows 4 Flow experience 4 Flow structure 4 Force-free magnetic fields 4 Gravity waves 4 Helicities 4 Ideal fluids 4 Initial conditions 4 Kelvin waves 4 Large-scale energy spectrum 4 Magnetic fields 4 Magnetohydrodynamics 4 Parametric spaces 4 Phenomenological theory 4 Random flows 4 Reynolds number 4