Author: National Aeronautics and Space Administration (NASA)

Publisher: Createspace Independent Publishing Platform

Published: 2018-05-29

Total Pages: 64

ISBN-13: 9781720448167

An experimental influence coefficient technique was used to obtain unsteady aerodynamic influence coefficients and, consequently, unsteady pressures for a cascade of symmetric airfoils oscillating in pitch about mid-chord. Stagger angles of 0 deg and 10 deg were investigated for a cascade with a gap-to-chord ratio of 0.417 operating at an axial Mach number of 1.9, resulting in a supersonic leading-edge locus. Reduced frequencies ranged from 0.056 to 0.2. The influence coefficients obtained determine the unsteady pressures for any interblade phase angle. The unsteady pressures were compared with those predicted by several algorithms for interblade phase angles of 0 deg and 180 deg.Ramsey, John K. and Erwin, DanGlenn Research CenterUNSTEADY AERODYNAMICS; INFLUENCE COEFFICIENT; PRESSURE MEASUREMENT; PRESSURE OSCILLATIONS; WIND TUNNEL TESTS; CASCADE FLOW; MACH NUMBER; SUPERSONIC FLUTTER; AIRFOIL OSCILLATIONS; PRESSURE DISTRIBUTION; SUPERSONIC WIND TUNNELS