Reddy, U.C., and Komerath, N.M. "3D Velocity Field Measurement in Large-Scale Rotor Flows", AIAA 99-3597, 30th AIAA Fluid Dynamics Meeting, June 1998, Norfolk, VA.

Planar velocity measurements in two rotorcraft flows are presented. The first is that of an isolated rotor in axial flight in a large settling chamber, with measurement parameters and test conditions typical of a full-scale rotor wake. The clean periodicity of this flow allows capture of fundamental cortex dynamics, as well as phase-resolved velocity measurements using an inexpensive white-light-based measurement system. The second flowfield is that of a rotor wake interacting with a fixed wing in a wind tunnel, representing many features of tiltrotor flows. This experiment was used as a test bed to develop and refine a technique to capture all 3 components of phase-resolved velocity over the volume of the interaction region. The velocity field is presented in several chordwise and spanwise sections as a function of rotor azimuth.

Complete Paper in PDF form