Experimental investigation of the rotor-wing aerodynamic interaction in a tiltwing aircraft in hover

The hovering performance and the lifting capability of tiltrotor aircraft are strongly affected by the aerodynamic interaction between wing and rotors. The tiltwing concept represents a promising technology to increase the hover performance by reducing the wing-rotor interference. The present work describes an experimental activity carried out on a 1⁄4 scaled tiltwing aircraft half-model to achieve a detailed insight about the main issues characterising the aerodynamic interaction between wing and rotor in hover. The results of the experimental campaign, including both force measurements and Particle Image Velocimetry surveys, enabled to evaluate both the aircraft performance for different configurations of the tilting wing and to achieve a detailed insight about the flow physics of the rotor wake in the interaction with the wing. The test activity provided a comprehensive experimental database that was obtained over a not confidential aircraft configuration. The AeronAuTicAl JournAl MAy 2015 VoluMe 119 no 1215 591 Paper No. 4236. Manuscript received 18 July 2014, revised version received 18 November 2014, accepted 9 January 2015. Experimental investigation of the rotor-wing aerodynamic interaction in a tiltwing aircraft in hover G. Droandi giovanni.droandi@polimi.it A. Zanotti, G. Gibertini, D. Grassi and G. campanardi Dipartimento di Scienze e Tecnologie Aerospaziali Politecnico di Milano Milano Italy https:/www.cambridge.org/core/terms. https://doi.org/10.1017/S0001924000010708 Downloaded from https:/www.cambridge.org/core. Open University Library, on 12 Feb 2017 at 17:31:40, subject to the Cambridge Core terms of use, available at 592 The AeronAuTicAl JournAl MAy 2015

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