Accession Number : AD0696158

Title :   STUDIES IN HOMOGENEOUS AND NONHOMOGENEOUS FREE TURBULENT SHEAR FLOWS,

Corporate Author : POLYTECHNIC INST OF BROOKLYN FARMINGDALE N Y DEPT OF AEROSPACE ENGINEERING AND APPLIED MECHANICS

Personal Author(s) : Trentacoste,Nicholas P. ; Sforza,Pasquale M.

Report Date : SEP 1969

Pagination or Media Count : 148

Abstract : An evaluation was made of the present state-of-the-art of turbulent mixing, by surveying the prevalent concepts and conclusions that have influenced research trends in this field. A critical discussion of the currently favored instruments used for obtaining measurements of the time mean properties of a turbulent flow is rendered; in addition, experimental evidence is presented to question the validity of such measurement techniques. A succinct description of the methodology utilized in ascertaining the consistency of experimental measurements with the particular properties of a given flow field is also discussed. An extension of the original Reichardt inductive theory of free turbulence is presented. This theory is utilized to solve the problem of a turbulent axisymmetric jet exhausting into a quiescent ambient under arbitrary initial conditions. The theory may be easily generalized to treat the more fashionable two stream mixing problem. Results of the analysis are compared with the mean property measurements of this investigation, and excellent agreement is obtained. Mean property measurements for initially axisymmetric and elliptic jets were obtained under isothermal, nonisothermal, homogeneous and nonhomogeneous conditions. Shadowgraph photography was employed to determine indicate its subsequent developments. (Author)

Descriptors :   (*TURBULENCE, *STATE-OF-THE-ART REVIEWS), (*JET MIXING FLOW, TURBULENCE), SHEAR STRESSES, THERMODYNAMICS, MEASUREMENT, FLOW FIELDS, AXIALLY SYMMETRIC FLOW, FLOW VISUALIZATION

Subject Categories : Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE