Tests were performed on a linear cascade of airfoils oscillating in pitch about their midchords at frequencies up to 17 cps, at velocities up to 200 ft/sec and at interblade phase angles of 0 and 45 deg, under conditions of high aerodynamic loading. The measured data included unsteady time histories from chordwise pressure transducers and chordwise hot films. Unsteady normal force coefficient, moment coefficient, and aerodynamic work per cycle of oscillation were obtained from integrals of the pressure data, and indications of the nature and extent of the separation phenomenon were obtained from an analysis in interblade phase angle from 0 deg to 45 deg radically alters the character of the blade loading (which govern its motion in a free system) from stable to unstable. Furthermore, the stability or instability is governed primarily by the phase angle of the pressure distribution over the forward 10 to 15 percent of the blade chord. Reduced frequency and mean incidence angle changes were found to have a relatively minor effect on stability for the range of parameters tested. (Kursetz)
An experimental study on the aerodynamic response of a subsonic cascade oscillating near stall
Eine experimentelle Untersuchung des aerodynamischen Verhaltens einer Unterschallkaskade nahe der Ueberzugsgrenze
US Government Research Reports ; 1-107
1976
107 Seiten
Report
English
Unsteady Aerodynamic Analysis of Subsonic Oscillating Cascade
Online Contents | 1994
|Unsteady aerodynamic loading computation for subsonic oscillating wing
British Library Online Contents | 1995
|