Mixing in modulated turbulence. Numerical results
  Direct numerical simulations are carried out to investigate scalar mixing in an isotropic turbulent flow with a time-periodic forcing. For high amplitudes of the modulation, it is shown that the average mixing rate is negatively affected at low frequencies. In this limit the mixing time scale increases, whereas the typical velocity timescale decreases. We further determine the frequency response of scalar statistics to a periodic scalar-forcing. 
Yuyao Yang (LMFA), Robert Chahine (LMFA), Robert Rubinstein, Wouter   Bos (LMFA)
physics.flu-dyn