Transition Detection on Rotating Propeller Blades by Means of Temperature Sensitive Paint

The laminar-to-turbulent boundary-layer transition on a high-speed rotating propeller was measured using Temperature-Sensitive Paint (TSP). The TSP formulation, the experimental set-up, the image acquisition, and processing procedure had been evaluated in a pretest. High resolution propeller images were obtained even at rotation speeds of 9600 rpm. Obtained temperature images clearly show the temperature steps due to the laminar-to-turbulent boundary layer transition. Based on the pretest results, a wind tunnel experiment was conducted in the low-speed wind-tunnel BLSWT of AIRBUS in Bremen at propeller rotation speeds up to 14400 rpm. The TSP results of the wind tunnel test visualized the development of laminar and turbulent regions on the propeller blade depending on propeller speed.