{ "id": "1505.07984", "version": "v1", "published": "2015-05-29T10:33:47.000Z", "updated": "2015-05-29T10:33:47.000Z", "title": "Turbulence on a Fractal Fourier set", "authors": [ "Alessandra Sabina Lanotte", "Roberto Benzi", "Luca Biferale", "Shiva Kumar Malapaka", "Federico Toschi" ], "categories": [ "physics.flu-dyn", "nlin.CD" ], "abstract": "The dynamical effects of mode reduction in Fourier space for three dimensional turbulent flows is studied. We present fully resolved numerical simulations of the Navier-Stokes equations with Fourier modes constrained to live on a fractal set of dimension D. The robustness of the energy cascade and vortex stretching mechanisms are tested at changing D, from the standard three dimensional case to a strongly decimated case for D = 2.5, where only about $3\\%$ of the Fourier modes interact. While the direct energy cascade persist, deviations from the Kolmogorov scaling are observed in the kinetic energy spectra. A model in terms of a correction with a linear dependency on the co-dimension of the fractal set, $E(k)\\sim k^{- 5/3 + 3 -D }$, explains the results. At small scales, the intermittent behaviour due to the vorticity production is strongly modified by the fractal decimation, leading to an almost Gaussian statistics already at D ~ 2.98. These effects are connected to a genuine modification in the triad-to-triad nonlinear energy transfer mechanism.", "revisions": [ { "version": "v1", "updated": "2015-05-29T10:33:47.000Z" } ], "analyses": { "keywords": [ "fractal fourier set", "triad-to-triad nonlinear energy transfer mechanism", "direct energy cascade persist", "turbulence", "fractal set" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }