The present paper concerns the original work undertaken atLABM to determine the boundary layer velocity distributionin the inboard region of a tiltrotor blade by use of anEmbedded Laser Doppler Velocimeter in a blade sectionclose to the hub. The experiments were carried out on a two bladed rotor with a blade geometry close to the one ofCAMRAD II model of TRAM. The blade section was explored in three chord stations, for 3 pitch angles, two ofthem at values lower than the static stall angle of incidence,the third at a higher value. Results obtained on the velocitycomponents have allowed characterizing the differentaspects of the BL. A delay of the BL separation due to therotation, has been observed at high incidence. The spanwisecomponent has been useful to specify if the flow over theblade section is centripetal or centrifugal. The present resultshave shown that the ELDV is quite able to measure velocityprofiles in the BL of a rotating blade and to qualify itsnature.
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