Numerical reproduction of turbulent flow field in a small patch of open ocean by low-wavenumber forcing

Abstract A method is proposed for the numerical reproduction of fluctuating flows in the small-scale ocean, based on single-point measurements in the real sea. Full-3D LES on the spatial scale of 50 m was conducted for this purpose. The reproduction of spatial information from the time-sequential data obtained at a single measurement point is theoretically impossible without any assumptions. We assumed spherically even distribution of energy for large eddies and Taylor’s frozen turbulence hypothesis. The extracted low-wavenumber components of fluctuation are forced in the whole computational domain and its high-wavenumber components evolve freely in the computation. The results of the present numerical method were validated by the smooth connectivity of frequency spectrum between low and high frequencies and by the slope of the wavenumber spectrum.