The results of large-eddy simulations (LES) are compared to measurements of a modelscale frigate wake. The measurements are compared to two types of large-eddy simulations: a nonlinear free-surface approach and a low Froude-number approximation. An unique procedure has been developed for initializing three-dimensional LES using two-dimensional measurements of the mean and fluctuating velocity fields of a cross section of the wake. The procedure also works well for extending Reynolds-averaged Navier-Stokes simulations of near-field flows into the far wake. The numerical results show that turbulent roughening of the ocean surface scales according to threedimensional similarity theory. An extensive in ertial range is established in the kinetic and potential energy spectras. There is no evidence of the effects of two-dimensional turbulence in the free-surface elevation. Based on analyses of energy spectra, third-order moments, and probability distributions, the performance of the Smagorinsky model is satisfactory in the inviscid limit. Preliminary results of some recent grid-stirred turbulence and splitter-plate experiments are discussed. The numerical predictions of the evolution of the wake agree well with towing-tank measurements.
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