Passive Scalars in Stratified Turbulence
نویسندگان
چکیده
The statistics of a passive scalar in randomly forced and strongly stratified turbulence is investigated by numerical simulations including a horizontal passive scalar mean gradient. We observe that horizontal isotropy of the passive scalar spectrum is satisfied in the inertial range. The spectrum has the form Eθ(kh) = Cθεθε −1/3 K k −5/3 h , where εθ, εK are the dissipation of scalar variance and kinetic energy respectively, and Cθ ' 0.5 is a constant. This spectrum is consistent with atmospheric measurements in the mesoscale range. The calculated passive scalar structure functions show that intermittency effects are significant.
منابع مشابه
Analytical and Numerical Studies on Stratified Fluid Flows
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