Accession Number : AD0628540

Title :   ISOTROPIC TURBULENCE AND INERTIAL-RANGE STRUCTURE IN THE ABRIDGED LHDI APPROXIMATION.

Descriptive Note : Research rept.,

Corporate Author : KRAICHNAN (ROBERT H) PETERBOROUGH N H

Personal Author(s) : Kraichnan,Robert H.

Report Date : JAN 1966

Pagination or Media Count : 89

Abstract : The abridged LHDI (Lagrangian-History Direct Interaction) closure approximation is interpreted physically and used to analyze energy transfer, effective eddy viscosities, and Lagrangian spacetime statistics in stationary and decaying isotropic turbulence. The results are then specialized to the inertial range. Numerical values are predicted for the Kolmogorov constant, the asymptotic eddy viscosities due to inertial-range wavenumbers, and the dimensionless constant in Inoue's formula for the mean-square change of Lagrangian velocity with time. Computed curves are presented for the localness of energy transfer, for Lagrangian spacetime structure functions, and for Lagrangian spacetime acceleration covariances. Inertial-range Eulerian spacetime structure functions also are computed. The predicted absolute Kolmogorov spectrum in the inertial and dissipation ranges is compared with data of Grant, Stewart, and Moilliet, and of M. M. Gibson. (Author)

Descriptors :   (*TURBULENCE, DYNAMICS), (*APPROXIMATION(MATHEMATICS), TURBULENCE), STATISTICAL MECHANICS, FLUID MECHANICS, ENERGY, MOMENT OF INERTIA, DIFFERENTIAL GEOMETRY

Subject Categories : Theoretical Mathematics
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE