PRESSURE MEASUREMENTS ON AN AEROFOIL DESIGNED FOR A 'ROOFTOP' TYPE OF PRESSURE DISTRIBUTION AT A CRITICAL MACH NUMBER OF 0.688

摘要

Pressure distributions have been measured, at Mach numbers up to 0.75, on a two-dimensional aerofoil. The aerofoil, 10.5 percent thick with a camber ratio of 0.06, has been designed to have an upper surface pressure distribution of the "rooftop" type at a critical Mach number of 0.688.nAt near-design conditions, it was found that the an-rimum suction on the aerofoil overshoots the predicted value significantly. This is caused by the inadequacy of the approximate potential flow calculations (Weber's method) as veil as by the approximate way in which the effect of viscosity has been taken into account in those calculations.