关键词: 紊流扩散;紊流模型;紊流传热;紊流

Abstract: Experimental data show that the transfer of scalar in turbulent flows is non-isotropic and the turbulent flux is at an angle with the mean scalar gradient in homogeneous isotropic turbulence. So the turbulent diffusiv-ity in gradient transfer model of scalar should be a second order tensor. In this paper a formula of the turbulent diffusivity tensor is derived, then the homogeneous isotropic turbulence, the homogeneous shear turbulence with a mean velocity gradient, the turbulent flux in a circle tube and in two-dimension plane jet are analysed and the results are satisfactory.

Key words: Turbulent diffusion;Turbulent model;Turbulence;Turbulence heat transfer