Time-resolved pressure measurements for an airfoil with self-sustained shock oscilations

Abstract

© 31st Congress of the International Council of the Aeronautical Sciences, ICAS 2018. All rights reserved.In order to understand the mechanisms behind self-sustained shockwave oscillations under laminar flow, the pressure distributions over a NACA 0012 airfoil with free transition were measured using two types of fast-response pressure-sensitive paints. The airfoil was submitted to flow near and at buffeting conditions. Pressure fields were analyzed using Power Spectral Density (PSD), Cross Power Spectral Density (CPSD) and pressure time-series standard deviation, as well as general flow visualization. Results indicate a clear shockwave oscillation frequency which does not match its turbulent flow counterpart. In addition, CPSD phase shift analysis allows the identification of different regions of shockwave interaction.

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