Additional Results of a Study of Unsteady Airfoil Surface Pressures and Turbulent Boundary Layers

Unsteady pressure coefficients measured on an N.A.C.A. 0012 airfoil at geometric angles of attack of 0 and 10 degrees, Reynolds numbers of 700,000 and 1,000,000 and in the reduced frequency range of 0.5 to 6.4 (based upon the half chord) are presented. For simplicity the data are represented in term...

Full description

Saved in:
Bibliographic Details
Main Authors: Covert, Eugene E, Lorber, Peter F
Format: Report
Language:English
Subjects:
AIRFOILS
ANGLE OF ATTACK
COEFFICIENTS
Fluid Mechanics
PE61102F
PRESSURE DISTRIBUTION
STEADY FLOW
Surface pressure
SURFACES
TRAILING EDGES
TURBULENT BOUNDARY LAYER
Unsteady boundary layer
UNSTEADY FLOW
Unsteady pressure
VARIATIONS
WIND TUNNEL TESTS
WUAFOSR2307A2
Online Access:Request full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Unsteady pressure coefficients measured on an N.A.C.A. 0012 airfoil at geometric angles of attack of 0 and 10 degrees, Reynolds numbers of 700,000 and 1,000,000 and in the reduced frequency range of 0.5 to 6.4 (based upon the half chord) are presented. For simplicity the data are represented in terms of mean and unsteady pressure coefficients, which has both a magnitude and a phase. Primary conclusions are: (1) The difference pressures approach zero at the trailing edge. This corresponds to satisfying one statement of the Kutta condition. (2) Superposition of the unsteady processes in the steady flow seems accurate and valid up to reduced frequencies of 2. (3) For this airfoil with 16 deg trailing edge angle the effects of viscosity seem to be most prominent in the last 10 percent of the airfoil where the phase lags are much larger than those predicted by the linear theory. (Author)