Turbulence on a fractally decimated Fourier set

Abstract eng:
One of the most distinct features of the physics of fluid dynamics turbulence is the intermittency of the flux of energy. Here we present a recently proposed approach (Lanotte et al., Phys. Rev. Lett. 115 2015) to investigate the nature of the energy transfer in incompressible, homogenous and isotropic turbulence. The Navier-Stokes equations are projected on a fractally decimated skeleton in Fourier space. The robustness of the energy transfer and of the vortex stretching are tested by changing the fractal dimension D in Fourier space, from D = 3 to D = 2.5 (where about 3% of the modes are retained). This approach allows to study the statistical properties of the energy cascade preserving the symmetries of the Navier-Stokes equations. We find that a direct energy flux is maintained while clear deviations from the Kolmogorov scaling are observed in the energy spectra. A simple phenomenological model to rationalize to explain our findings is suggested.

• Export as: BibTeX | MARC | MARCXML | DC | EndNote | NLM | RefWorks
• Add to your basket