A Lagrangian model for turbulent dispersion with turbulent-like flow structure: Comparison with direct numerical simulation for two-particle statistics
نویسندگان
چکیده
A wide range of relative two-particle dispersion statistics from the Lagrangian Kinematic Simulation ~KS! model, which contains turbulent-like flow structures, compares well with Yeung’s @Phys. Fluids 6, 3416 ~1994!# DNS results. In particular, the Lagrangian flatness factor m4(t) compares excellently ~better than Heppe’s @J. Fluid Mech. 357, 167 ~1998!# nonlinear stochastic model!. For higher Reynolds numbers the results from KS show that m4(t) is significantly greater than 3 over a wide range of times within the inertial range of time scales. © 1999 American Institute of Physics. @S1070-6631~99!02706-3#
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