Inflow Measurements made with a Laser Velocimeter on a Helicopter Model in Forward Flight. Volume 6. Rectangular Planform Blades at an Advance Ratio of 0.35.

摘要

An experimental investigation was conducted in the 14- by 22-Foot subsonic Tunnel at the NASA Langley Research Center to measure the inflow into a scale model helicopter rotor in forward flight (micro = 0.35). The measurements were made with a two-component Laser Velocimeter (LV) one chord above the plane formed by the path of the rotor tips (tip-path-plane). A conditional sampling technique was used to determine the position of the rotor at the time that each velocity measurement was made so that the azimuthal fluctuations in velocity could be determined. Measurements were made at a total of 179 separate locations in order to clearly define the inflow character. (Author)