English

The Anomalous Scaling Exponents of Turbulence in General Dimension from Random Geometry

Chaotic Dynamics 2015-10-28 v3 High Energy Physics - Theory Fluid Dynamics

Abstract

We propose an exact analytical formula for the anomalous scaling exponents of inertial range structure functions in incompressible fluid turbulence. The formula is a gravitational Knizhnik-Polyakov-Zamolodchikov (KPZ)-type relation, and is valid in any number of space dimensions. It incorporates intermittency by gravitationally dressing the Kolmogorov linear scaling via a coupling to a random geometry. The formula has one real parameter γ\gamma that depends on the number of space dimensions. The scaling exponents satisfy the convexity inequality, and the supersonic bound constraint. They agree with the experimental and numerical data in two and three space dimensions, and with numerical data in four space dimensions. Intermittency increases with γ\gamma, and in the infinite γ\gamma limit the scaling exponents approach the value one, as in Burgers turbulence. At large nn the nnth order exponent scales as n\sqrt{n}. We discuss the relation between fluid flows and black hole geometry that inspired our proposal.

Keywords

Cite

@article{arxiv.1502.03069,
  title  = {The Anomalous Scaling Exponents of Turbulence in General Dimension from Random Geometry},
  author = {Christopher Eling and Yaron Oz},
  journal= {arXiv preprint arXiv:1502.03069},
  year   = {2015}
}

Comments

18 pages, 3 figures; v3: additional clarifications, added references; v2: improved discussion, added one figure