Accession Number : AD0711313

Title :   A STUDY OF FLOW FROM TWO PLANAR NOZZLES.

Descriptive Note : Technical rept.,

Corporate Author : LEHIGH UNIV BETHLEHEM PA DEPT OF MECHANICAL ENGINEERING AND MECHANICS

Personal Author(s) : Owczarek,Jerzy A. ; Rockwell,Donald O. ; Cha,Y-S.

Report Date : JUN 1970

Pagination or Media Count : 44

Abstract : The report describes an experimental investigation of the characteristics of low-Mach number flow of air from each of two planar nozzles having an aspect ratio of 3 at the exit. The nozzles had rectangular inlets with rounded leading edges to channel the flow from round stagnation tanks. The nozzle which produced nonuniform flow at the exit was tested with and without a flow straightener inside. Most experiments were performed at the Reynolds number, based on the width of the nozzle at the exit and on the average flow speed at the nozzle exit, of 12,400. The tests showed that the planar convergent nozzle having a concave-convex inner wall profile, without a flow straightener in it, produced a very nonuniform total pressure distribution at the exit. The flow visualization study showed that the regions of low total pressure are associated with vortices whose axes have the general direction of the main flow. The planar convergent nozzle having a concave-straight inner wall profile, tested without a flow straightener in it, produced uniform total pressure distribution at the exit outside of the boundary-layer region. Small concentrated vortices were observed to exist inside both nozzles. (Author)

Descriptors :   (*NOZZLE GAS FLOW, *FLUID AMPLIFIERS), JETS, ASPECT RATIO, LEADING EDGES, REYNOLDS NUMBER, PRESSURE, DISTRIBUTION, VORTICES

Subject Categories : Aerodynamics
      Fluidics and Fluerics

Distribution Statement : APPROVED FOR PUBLIC RELEASE