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CFD analysis of hover performance of rotors at full- and model-scale conditions

Published online by Cambridge University Press:  13 June 2016

G.N. Barakos*
Affiliation:
CFD Laboratory, School of Engineering, James Watt South Building, University of Glasgow, Glasgow, United Kingdom
A. Jimenez Garcia
Affiliation:
CFD Laboratory, School of Engineering, James Watt South Building, University of Glasgow, Glasgow, United Kingdom

Abstract

Analysis of the performance of a 1/4.71 model-scale and full-scale Sikorsky S-76 main rotor in hover is presented using the multi-block computational fluid dynamics (CFD) solver of Glasgow University. For the model-scale blade, three different tip shapes were compared for a range of collective pitch and tip Mach numbers. It was found that the anhedral tip provided the highest Figure of Merit. Rigid and elastic full-scale S-76 rotor blades were investigated using a loosely coupled CFD/Computational Structural Dynamics (CSD) method. Results showed that aeroelastic effects were more significant for high thrust cases. Finally, an acoustic study was performed in the tip-path-plane of both rotors, showing good agreement in the thickness and loading noise with the theory. For the anhedral tip of the model-scale blade, a reduction of 5% of the noise level was predicted. The overall good agreement with the theory and experimental data demonstrated the capability of the present CFD method to predict rotor flows accurately.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 2016 

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