Steady and unsteady transonic pressure distributions on NACA 0012

Abstract

Steady and unsteady aerodynamic data were measured on a two-dimensional model with an airfoil of 12% thickness mounted in the transonic wind tunnel of the DFVLR in Gottingen. The profile was oscillated in pitch about its c/4 axis to generate the unsteady aerodynamic pressure data. The primary purpose of the wind tunnel test was to measure data for use in the development and assessment of transonic analytical codes and to show the dependence of aerodynamic responses on the following parameters: Mach number (0.5-1.0), reduced frequency (0.2-0.12), angle of attack (0-9 deg), and oscillation amplitude (0.5-2.5 deg). Emphasis is also placed on the nonlinearities that actually occur and that are peculiar to higher angles of attack. Steady and unsteady calculation results agreed fairly well with the measured data.