A Stochastic Analysis of the Displacements of Fluid Elements in Inhomogeneous Turbulence Using Kraichnan’s Method of Random Modes

摘要: At an instant in time a homogeneous turbulent flow field can be represented as summation of random Fourier components; this extended to describe turbulence near interface or boundary shear-free flow, by adding irrotational velocity field. The evolution the simulated assuming that modes are oscillatory functions with frequencies and amplitudes: i) our model simulates energy containing eddies inertial subrange (5/3) spectrum; ii) scale for decorre lation each eddy is made proportional its length-scale corresponding Eulerian power spectrum ω −5/3.