TY - JOUR ID - 21200 TI - Experimental investigation of shock wave oscillation on a thin supercritical airfoil JO - Scientia Iranica JA - SCI LA - en SN - 1026-3098 AU - Masdari, M. AU - Talebi, M. AU - Zeinalzadeh, A. AU - Abdi, M.A. AU - Soltani, M. R. AD - Faculty of New Sciences and Technologies, University of Tehran, Tehran, 1417614418, Iran AD - Department of Aerospace Engineering, Sharif University of Technology, Azadi Ave., Tehran, Zip Code: 1458889694, Iran Y1 - 2020 PY - 2020 VL - 27 IS - 2 SP - 795 EP - 805 KW - Pressure Distribution KW - Supercritical airfoil KW - Transonic regime KW - Shock wave KW - Unsteady wake KW - buffet phenomenon KW - Angles of attack KW - Cross-correlation technique KW - Schlieren imaging DO - 10.24200/sci.2018.51306.2104 N2 - 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 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. The frequency of the shock wave oscillation and unsteady wake behaviour at a freestream Mach no. of M=0.6 and at different angles of attacks are measured using cross-correlation technique by means of pressure sensors locating 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. UR - https://scientiairanica.sharif.edu/article_21200.html L1 - https://scientiairanica.sharif.edu/article_21200_61e93c200dd6f7fb002f8425fa7d304a.pdf ER -