On the evolution of decaying isotropic turbulence

A direct numerical simulation is performed on 256³ grids for decaying isotropic turbulence. The total kinematic energy, Taylor micro-scale, Taylor micro-scale Reynolds number and the velocity derivative skewness are calculated. The snapshots of energy spectra and energy transfer spectra are plotted. These measurements verify the DIA predictions: decaying isotropic turbulence has the energy propagation and occupies the final decay periods. The skewness remains to some level with small variation even in the final decay period.