Accession Number : AD0885291

Title :   Decay of Boundary Layer Turbulence in the Near Wake Expansion Region of a Slender Body.

Descriptive Note : Research rept.,

Corporate Author : AVCO EVERETT RESEARCH LAB INC EVERETT MA

Personal Author(s) : Pirri, Anthony N.

Report Date : JUN 1971

Pagination or Media Count : 53

Abstract : A theoretical study of the decay of the fluctuating velocities in the supersonic near wake expansion of boundary layer turbulence is presented. A model based on linear theories is utilized to predict the change in fluctuation levels and turbulent scale sizes. The effect of the compressibility of the mean flow is included, and mean properties are calculated from method of characteristics solutions. The validity of linear theory is examined, and an analysis of the decay of eddy turbulence associated with the vorticity field is presented. Results indicate that the decay rate is strongly dependent upon proper specification of the anisotropic boundary layer turbulence. Results consistent with data for the turbulence decay in the near wake of a slender wedge are obtained when a realistic choice of boundary layer integral scales and velocity fluctuation levels is made. (Author)

Descriptors :   *WAKE), (*REENTRY VEHICLES, TURBULENT BOUNDARY LAYER, SUPERSONIC CHARACTERISTICS, SLENDER BODIES, COMPRESSIVE PROPERTIES, VORTICES, FLOW FIELDS, ANALYSIS OF VARIANCE.

Subject Categories : Guided Missile Reentry Vehicles
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE