Experimental investigation of shock wave oscillation on a thin supercritical airfoil

Experimental results of surface pressure distribution over a thin supercritical airfoil and its wake are presented. All tests were conducted at free stream Mach numbers ranging from 0.27 to 0.85 and at different angles of attacks in a transonic wind tunnel. The model was equipped with static pressur...

Full description

Saved in:
Bibliographic Details
Published inScientia Iranica. Transaction B, Mechanical engineering Vol. 27; no. 2; pp. 795 - 805
Main Authors Masdari, M, Talebi, M, Zeinalzadeh, A, Abdi, M A, Soltani, M R
Format Journal Article
LanguageEnglish
Published Tehran Sharif University of Technology 01.03.2020
Subjects
Aircraft
Angle of attack
Boundary layers
Correlation analysis
Fourier transforms
Mach number
Orifices
Pressure
Pressure distribution
Pressure sensors
Reynolds number
Shock waves
Static pressure
Stress concentration
Suction
Supercritical airfoils
Transducers
Transonic wind tunnels
Online AccessGet full text

Cover

More Information
Summary:Experimental results of surface pressure distribution over a thin supercritical airfoil and its wake are presented. All tests were conducted at free stream Mach numbers ranging from 0.27 to 0.85 and at different angles of attacks in a transonic wind tunnel. The model was equipped with static pressure orifices connected to high-frequency pressure transducers. The present paper evaluates variations of shock wave location with both Mach number and angle of attack variation, as well as its interaction with the boundary layer, leading to the buffet phenomenon. Note that, for this thin supercritical airfoil, there exist only a few experimental results regarding surface pressure distributions, corresponding forces and moments, and the shock wave oscillations and its behavior with various flow conditions. The frequency of the shock wave oscillation and unsteady wake behavior at a freestream Mach no. of = 0.66 and at different angles of attacks are measured by the cross-correlation technique by means of pressure sensors located on the suction side of the model and via the rake total pressure data that was traversed vertically behind the model, respectively. From the analysis of surface pressure distribution and wake data, drag divergence occurred at a certain angle of attack and at a frequency equal to the shock wave oscillation frequency.
DOI:10.24200/sci.2018.51306.2104