Flow Measurement Study Of Rotor-fuselage Aerodynamic Interaction

Rotor is the key part of helicopters, Rotor wake flow field analysis is one of the most importantissues of helicopter aerodynamics, and it is also the important bases of the study on helicopter flightcharacteristics, rotor loads, vibration, noise, maneuverability and stability. Moreover, it is a veryimportant mean of helicopter aerodynamic interaction.Helicopter aerodynamics is one of the most difficult and complex field of aerodynamics, it isbecause rotor induce a complex wake. It contains a variety of complex aerodynamic characteristics,such as the overall rotational flow field, unsteady, nonlinear, three-dimensional effect, flow in theblade tip vortex structure of blade, blade vortex interactions, flow separation and periodic transonicmovement of advancing blade, rotor-fuselage aerodynamic interaction especially in low speed flightstate. These problems make the study of rotor wake becomes very difficult. However, thevisualization and measurement of rotor flow fields become possible because of the rapid developmentof the modern flow visualization technique and flow field measurement technology. Especially,Doppler laser velocimetry (LDV) technology, particle image velocimetry (PIV) technology, opticalflow visualization technique has been successfully applied to the rotor wake flow field measurement.This paper presents wind tunnel experimental study of helicopter rotor-fuselage flow field.Several test campaigns have been conducted in the subsonic wind tunnel in the Nanjing University ofAeronautics and Astronautics on a Robin model equipped with a powered main rotor. The preparationworks before test, method and procedure of test and techniques of test are introduced in this paper.Thus, we provided important test basis for other research.