Models of intermittency in hydrodynamic turbulence

Journal Article · Mon Jul 30 04:00:00 EDT 1990 · Physical Review Letters; (USA)

DOI:https://doi.org/10.1103/PhysRevLett.65.575· OSTI ID:6607600

Kraichnan, R H ^[1]

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1. 303 Potrillo Drive, Los Alamos, NM (USA)

A heurisitic model for evolution of the probability distribution (PDF) of transverse velocity gradient {ital s} in incompressible Navier-Stokes turbulence is distilled from an analytical closure for Burgers turbulence. At all Reynolds number {ital scrR}, the evolved PDF is {proportional to}{vert bar}{ital s}{vert bar}{sup {minus}1/2} exp({minus}const{times}{vert bar}{ital s}{vert bar}/{l angle}{ital s}{sup 2}{r angle}{sup 1/2}) for large {vert bar}{ital s}{vert bar}. The model suggests that skewness and flatnesses are asymptotically independent of {ital scrR}, and that cascade to smaller scales is not a fractal process. For Burgers dynamics, both simulations and the analytical closure give a PDF {proportional to}{vert bar}{xi}{vert bar}{sup {minus}1} exp({minus}const{times}{vert bar}{xi}{vert bar}/{l angle}{xi}{sup 2}{r angle}{sup 1/2}) for large negative velocity gradient {xi}.

• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 6607600
• Journal Information: Physical Review Letters; (USA), Journal Name: Physical Review Letters; (USA) Vol. 65:5; ISSN PRLTA; ISSN 0031-9007
• Country of Publication: United States
• Language: English

Related Subjects

640410* -- Fluid Physics-- General Fluid Dynamics
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
AMPLITUDES
ASYMPTOTIC SOLUTIONS
DIFFERENTIAL EQUATIONS
EQUATIONS
FLOW MODELS
FLUID FLOW
FLUID MECHANICS
FRACTALS
HYDRODYNAMICS
INCOMPRESSIBLE FLOW
MAPPING
MATHEMATICAL MODELS
MECHANICS
NAVIER-STOKES EQUATIONS
PARTIAL DIFFERENTIAL EQUATIONS
PROBABILITY
REYNOLDS NUMBER
SIMULATION
TURBULENCE
TURBULENT FLOW
VELOCITY