Effects of duct shape on a ducted propeller performance

Abstract

Performance characteristics and velocity field of a ducted propeller in hover and axial flight conditions are investigated experimentally. Five different circular duct shapes has been tested. Effect of duct geometry is studied by means of measurements at various flow conditions. Velocity field upstream and downstream of the propeller, axial force acting on each component of the propulsive system, rotor speed and torque are measured. Pressure distribution on duct inner and outer surfaces is also investigated. Experimental results obtained for open and ducted propellers are compared