Transition Detection and Skin Friction Measurements on Rotating Propeller Blades

Abstract

The laminar-to-turbulent transition on high-speed rotating propeller blades is investigated in the present work experimentally. The analysis of limitations for optical skin-friction measurements by the oil-film interferometry, as well as of the results of feasibility experiments in the low-speed wind-tunnel BLSWT of AIRBUS Bremen at propeller rotation rates from 3000 up to 14400 rpm (50-240 Hz) and free-stream flow speeds between 30 and 70 m/s are included. The effects of Reynolds number and of the propeller advance ratio on the transition location and flow topology are discussed.