English

Casimir preserving spectrum of two-dimensional turbulence

Fluid Dynamics 2024-11-28 v2

Abstract

We present predictions of the energy spectrum of forced two-dimensional turbulence obtained by employing a structure-preserving integrator. In particular, we construct a finite-mode approximation of the Navier-Stokes equations on the unit sphere, which, in the limit of vanishing viscosity, preserves the Lie-Poisson structure. As a result, integrated powers of vorticity are conserved in the inviscid limit. We obtain robust evidence for the existence of the double energy cascade, including the formation of the -3 scaling of the inertial range of the direct cascade. We show that this can be achieved at modest resolutions compared to those required by traditional numerical methods.

Keywords

Cite

@article{arxiv.2204.11794,
  title  = {Casimir preserving spectrum of two-dimensional turbulence},
  author = {Paolo Cifani and Milo Viviani and Erwin Luesink and Klas Modin and Bernard J. Geurts},
  journal= {arXiv preprint arXiv:2204.11794},
  year   = {2024}
}