Accession Number : AD0718274

Title :   Transient Flows in Short Curved Diffusers,

Corporate Author : SASKATCHEWAN UNIV SASKATOON DEPT OF MECHANICAL ENGINEERING

Personal Author(s) : Deckker,B. E. L. ; Ramakrishnan,T. K. ; Male,D. H.

Report Date : 15 SEP 1969

Pagination or Media Count : 12

Abstract : The work reported is the first stage of an investigation into the effect of pressure waves of varying amplitude on the flow through the blade passages of turbomachines. Attention is confined to the interaction between the pressure wave and the geometry of four curved diffusers with the same area distribution about a circular-arc centre-line. The geometry of these diffusers is based on a straight diffuser with a total divergence angle equal to 12 deg and a length of 5 in. The nominal turning angles are 30, 45, 60, and 90 deg. The transient flow through the five diffusers was compared on the basis of sequences of Schlieren photographs taken at 50 microsec intervals. The attenuation of the wave at the curved walls was also measured. Systematic measurements were made of the net and transmitted pressures, and also the pressures on the curved walls, during the quasi-steady regime. An attempt was made to predict the net and transmitted pressures by means of two simple analyses, one of which is moderately successful. Diffuser effectiveness was compared under conditions of steady and quasi-steady flow. (Author)

Descriptors :   (*DIFFUSERS, *GAS FLOW), CURVED PROFILES, GAS TURBINES, INTERACTIONS, PRESSURE, FLOW VISUALIZATION, CANADA

Subject Categories : Aerodynamics
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE