Turbulence Structure Functions

S_p(r) = ⟨|δu(r)|^p⟩ ~ r^ζ_p — Kolmogorov K41 vs She-Leveque intermittency

Structure Functions S_p(r) (log-log)

Anomalous Exponents ζ_p

Parameters

ζ₂ (K41): 2/3
ζ₂ (SL):
ζ₃ (exact): 1.000
ζ₆ (SL):
Inertial range:
K41: ζ_p = p/3 (Kolmogorov 1941)
SL: ζ_p = p/9 + 2[1−(2/3)^(p/3)] (She-Leveque 1994)
ζ₃ = 1 exactly (4/5 law, rigorous)
Intermittency: dissipation is multifractal

Velocity Increment PDF (Gaussian vs Stretched-Exp)