Turbulent thermal diffusion in strongly stratified turbulence: theory and experiments Academic Article uri icon

abstract

  • Turbulent thermal diffusion is a combined effect of the temperature stratified turbulence and inertia of small particles. It causes the appearance of a nondiffusive turbulent flux of particles in the direction of the turbulent heat flux. This nondiffusive turbulent flux of particles is proportional to the product of the mean particle number density and the effective velocity of inertial particles. The theory of this effect has been previously developed only for small temperature gradients and small Stokes numbers [Phys. Rev. Lett. 76, 224 (1996)]. In this study, a generalized theory of turbulent thermal diffusion for arbitrary temperature gradients and Stokes numbers has been developed. The laboratory experiments in the oscillating grid turbulence and in the multifan produced turbulence have been performed to validate the theory of turbulent thermal diffusion in strongly stratified turbulent flows. It has been …

publication date

  • June 12, 2017