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Numerical analysis of a leading edge tubercle hydrofoil in turbulent regime

Published online by Cambridge University Press:  06 September 2019

Blanca Pena*
Affiliation:
Department of Mechanical Engineering, University College London, London WC1E 7JE, UK
Ema Muk-Pavic
Affiliation:
Department of Mechanical Engineering, University College London, London WC1E 7JE, UK
Giles Thomas
Affiliation:
Department of Mechanical Engineering, University College London, London WC1E 7JE, UK
Patrick Fitzsimmons
Affiliation:
Department of Mechanical Engineering, University College London, London WC1E 7JE, UK
*
Email address for correspondence: blanca.pena.16@ucl.ac.uk

Abstract

This paper presents a numerical performance evaluation of the leading edge tubercles hydrofoil with particular focus on a fully turbulent flow regime. Efforts were focused on the setting up of an appropriate numerical approach required for an in-depth analysis of this phenomenon, being able to predict the main flow features and the hydrodynamic performance of the foil when operating at high Reynolds numbers. The numerical analysis was conducted using an improved delayed detached eddy simulation for Reynolds numbers corresponding to the transitional and fully turbulent flow regimes at different angles of attack for the pre-stall and post-stall regimes. The results show that tubercles operating in turbulent flow improve the hydrodynamic performance of the foil when compared to a transitional flow regime. Flow separation was identified behind the tubercle troughs, but was significantly reduced when operating in a turbulent regime and for which we have identified the main flow mechanisms. This finding confirms that the tubercle effect identified in a transitional regime is not lost in a turbulent flow. Furthermore, when the hydrofoil operates in the turbulent flow regime, the transition to a turbulent regime takes place further upstream. This phenomenon suppresses a formation of a laminar separation bubble and therefore the hydrofoil exhibits a superior hydrodynamic performance when compared to the same foil in the transitional regime.

Type
JFM Papers
Copyright
© 2019 Cambridge University Press 

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References

Arolla, S. K. & Durbin, P. A. 2013 Modeling rotation and curvature effects within scalar eddy viscosity model framework. Intl J. Heat Fluid Flow 39, 7889.Google Scholar
Bolzon, M. D., Kelso, R. M. & Arjomandi, M. 2015 Tubercles and their applications. J. Aerospace Engng. 29, 04015013.Google Scholar
Fish, F. E. & Battle, J. M. 1995 Hydrodynamic design of the humpback whale flipper. J. Morphol. 225, 5160.Google Scholar
Hansen, K. L.2012. Effect of leading edge tubercles on airfoil performance. PhD thesis, School of Mechanical Engineering, University of Adelaide.Google Scholar
Hussain, F. & Jeong, J. 1995 On the identification of a vortex. J. Fluid Mech. 285, 6994.Google Scholar
Johari, H., Henoch, C., Custodio, D. & Levshin, A. 2007 Effects of leading-edge protuberances on airfoil performance. AIAA J. 45, 26342642.Google Scholar
Miklosovic, D. S., Murray, M. M. & Howle, L. E. 2007 Experimental evaluation of sinusoidal leading edges. J. Aircraft 44, 14041412.Google Scholar
Miklosovic, D. S., Murray, M. M., Howle, L. E. & Fish, F. E. 2004 Leading-edge tubercles delay stall on humpback whale (Megaptera novaeangliae) flippers. Phys. Fluids 16, 3942.Google Scholar
Pedro, H. T. C. & Kobayashi, M. H. 2008 Numerical study of stall delay on humpback whale flippers. In 46th AIAA Aerospace Sciences Meeting and Exhibit. AIAA.Google Scholar
Rostamzadeh, N., Hansen, K. L., Kelso, R. M. & Dally, B. B. 2014 The formation mechanism and impact of streamwise vortices on NACA 0021 airfoil’s performance with undulating leading edge modification. Phys. Fluids 26, 107101.Google Scholar
Rostamzadeh, N., Kelso, R. M. & Dally, B. 2017 A numerical investigation into the effects of Reynolds number on the flow mechanism induced by a tubercled leading edge. Theor. Comput. Fluid Dyn. 31, 132.Google Scholar
Serson, D., Eneghini, J. R. & Herwin, S. J. 2017 Direct numerical simulations of the flow around wings with spanwise waviness. J. Fluid Mech. 826, 714731.Google Scholar
Shur, M. L., Spalart, P. R., Strelets, M. K. & Travin, A. K. 2008 A hybrid RANS-LES approach with delayed-DES and wall-modelled LES capabilities. Intl J. Heat Fluid Flow 29, 16381649.Google Scholar
Skillen, A., Revell, A., Pinelli, A., Piomelli, U. & Favier, J. 2015 Flow over a wing with leading-edge undulations. AIAA J. 53, 464472.Google Scholar
Stanway, M. J.2008. Hydrodynamic effects of leading-edge tubercles on control surfaces and in flapping foil propulsion. Masters thesis, Department of Mechanical Engineering, Massachusetts Institute of Technology, MA.Google Scholar
Watts, P. & Fish, F. E. 2001 The influence of passive, leading edge tubercles on wing performance. In Proceedings of the 12th International Symposium on Unmanned Untethered Submersible Technology, Durham, New Hampshire. Autonomous Undersea Systems Institute.Google Scholar
Weber, P. W., Howle, L. E., Murray, M. M. & Miklosovic, D. S. 2011 Computational evaluation of the performance of lifting surfaces with leading-edge protuberances. J. Aircraft. 48, 591604.Google Scholar
Zhao, M., Zhang, M. & Xu, J. 2017 Numerical simulation of flow characteristics behind the aerodynamic performances on an airfoil with leading edge protuberances. Engng Appl. Comput. Fluid Mech. 11, 193209.Google Scholar