Tiltrotor CFD part II: aerodynamic optimisation of tiltrotor blades

Jimenez Garcia, A., Biava, M., Barakos, G.N. , Baverstock, K.D., Gates, S. and Mullen, P. (2017) Tiltrotor CFD part II: aerodynamic optimisation of tiltrotor blades. Aeronautical Journal, 121(1239), pp. 611-636. (doi: 10.1017/aer.2017.21)

Abstract

This paper presents aerodynamic optimisation of tiltrotor blades with high-fidelity computational fluid dynamics. The employed optimisation framework is based on a quasi-Newton method, and the required high-fidelity flow gradients were computed using a discrete adjoint solver. Single-point optimisations were first performed, to highlight the contrasting requirements of the helicopter and aeroplane flight regimes. It is then shown how a trade-off blade design can be obtained using a multi-point optimisation strategy. The parametrisation of the blade shape allowed to modify the twist and chord distributions, and to introduce a swept tip. The work shows how these main blade shape parameters influence the optimal performance of the tiltrotor in helicopter and aeroplane modes, and how a compromise blade shape can increase the overall tiltrotor performance. Moreover, in all the presented cases, the accuracy of the adjoint gradients resulted in a small number of flow evaluations for finding the optimal solution, thus indicating gradient-based optimisation as a viable tool for modern tiltrotor design.

• Item Type: Articles
• Additional Information: Results were obtained using the EPSRC funded ARCHIE-WeSt High Performance Computer (www.archie-west.ac.uk), EPSRC grant no. EP/K000586/1. Part of this work is funded under the HiperTilt Project of the UK Technology Strategy Board (TSB) and Leonardo Helicopters under Contract Nr. 101370. The research leading to these results has also received funding from the European Union Seventh Framework Programme FP7/2007-2013 under grant agreement n◦ 264672.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Barakos, Professor George and Biava, Dr Massimo and Jimenez Garcia, Mr Antonio
• Authors: Jimenez Garcia, A., Biava, M., Barakos, G.N., Baverstock, K.D., Gates, S., and Mullen, P.
• College/School: College of Science and Engineering > School of Engineering > Autonomous Systems and Connectivity
• Journal Name: Aeronautical Journal
• Publisher: Royal Aeronautical Society
• ISSN: 0001-9240
• ISSN (Online): 2059-6464
• Published Online: 05 May 2017
• Copyright Holders: Copyright © 2017 Royal Aeronautical Society
• First Published: First published in Aeronautical Journal 121(1239): 611-636
• Publisher Policy: Reproduced in accordance with the copyright policy of the publisher