Accession Number : AD0707076

Title :   THE EFFECT OF WALL POROSITY ON THE STABILITY OF PARALLEL FLOWS OVER COMPLIANT BOUNDARIES,

Corporate Author : NAVAL SHIP RESEARCH AND DEVELOPMENT CENTER WASHINGTON D C

Personal Author(s) : Burden,Harvey W.

Report Date : FEB 1970

Pagination or Media Count : 166

Abstract : An analytical investigation is made of the effect of wall porosity upon the stability of quasi-parallel laminar flows along plaine compliant boundaries of several types. A numerical technique is employed for solution of the coupled Orr-Sommerfeld/stress-strain/strain rate equations for incompressible, viscous fluid flowing over a porous, compliant, visco-elastic boundary. The analytical and numerical methods are described in detail. The results are compared with those of comparable situations without porosity, which, in turn, are compared with results of previous investigations, both analytical and empirical. Spatial amplification rates, velocity perturbation profiles, and Reynolds stress profiles are shown for a selected number of conditions. Basic analysis is presented for the case of parallel flow through a uniform circular cylindrical tube with similar wall characteristics. Numerical results are not presented; however, the direction of such future investigation is indicated. (Author)

Descriptors :   (*LAMINAR FLOW, FLEXIBLE STRUCTURES), (*WALLS, *POROSITY), STABILITY, VISCOELASTICITY, EQUATIONS OF MOTION, SKIN FRICTION, REDUCTION, NUMERICAL ANALYSIS, SHEAR STRESSES, BOUNDARY LAYER, SHIP HULLS

Subject Categories : Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE