Hostname: page-component-586b7cd67f-t7czq Total loading time: 0 Render date: 2024-11-24T01:34:00.777Z Has data issue: false hasContentIssue false

Critical indicators of dynamic stall vortex

Published online by Cambridge University Press:  28 February 2022

Xiao Li
Affiliation:
Fluid Mechanics Key Laboratory of Education Ministry, Beijing University of Aeronautics and Astronautics, Beijing 100191, PR China
Li-Hao Feng*
Affiliation:
Fluid Mechanics Key Laboratory of Education Ministry, Beijing University of Aeronautics and Astronautics, Beijing 100191, PR China
*
Email address for correspondence: lhfeng@buaa.edu.cn

Abstract

During a dynamic stall process, various flow structures leave their pressure footprints on a wing surface, through which it is possible to understand the development of different flow stages and predict the critical flow events. Based on a classical airfoil ramp-up pitching motion, proper orthogonal decomposition analysis of pressure on the suction surface is carried out in this study. Accordingly, the surface pressure evolution during dynamic stall is summarized into three basic physical schemas, based on which several real-time critical indicators for predicting the flow events related to the dynamic stall vortex (DSV) are constructed. These critical indicators include the spatial distribution coefficient of pressure (SDCP), the high-order central moment of pressure (HCMP), the location of peak pressure (LPP) and the modulated location of peak pressure (MLPP). These indicators can predict the formation of laminar separation bubbles, DSV initiation, DSV centre position and the detachment of DSV. Therefore, the real-time whole-life monitoring of DSV has been realized. Moreover, the effectiveness of these indicators has also been confirmed under different parameters, and testing using wind tunnel experimental data proves their noise robustness. Studies show that the SDCP and HCMP may also be effective even if only two transducers are used. Finally, a modification method of SDCP based on Z-score standardized pressure is proposed. It is found that the modified SDCP can effectively reduce sensitivity to kinematic parameters and the Reynolds number. The critical indicators in this study can be used as a reference for the standardized mathematical and physical description of DSV evolution, thus laying a foundation for constructing a universal theoretical framework of dynamic stall.

Type
JFM Papers
Copyright
© The Author(s), 2022. Published by Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Akkala, J.M. & Buchholz, J.H.J. 2017 Vorticity transport mechanisms governing the development of leading-edge vortices. J. Fluid Mech. 829, 512537.CrossRefGoogle Scholar
Amini, Y., Kianmehr, B. & Emdad, H. 2019 Dynamic stall simulation of a pitching hydrofoil near free surface by using the volume of fluid method. Ocean Engng 192, 106553.CrossRefGoogle Scholar
Andersen, A., Bohr, T., Schnipper, T. & Walther, J.H. 2017 Wake structure and thrust generation of a flapping foil in two-dimensional flow. J. Fluid Mech. 812, R4.CrossRefGoogle Scholar
Ansell, P.J. & Mulleners, K. 2020 Multiscale vortex characteristics of dynamic stall from empirical mode decomposition. AIAA J. 58, 600617.CrossRefGoogle Scholar
Benard, N., Cattafesta, L.N., Moreau, E., Griffin, J. & Bonnet, J. 2011 On the benefits of hysteresis effects for closed-loop separation control using plasma actuation. Phys. Fluids 23, 083601.CrossRefGoogle Scholar
Benton, S.I. & Visbal, M.R. 2019 The onset of dynamic stall at a high, transitional Reynolds number. J. Fluid Mech. 861, 860885.CrossRefGoogle Scholar
Corke, T.C. & Thomas, F.O. 2015 Dynamic stall in pitching airfoils: aerodynamic damping and compressibility effects. Annu. Rev. Fluid Mech. 47, 479505.CrossRefGoogle Scholar
Deparday, J. & Mulleners, K. 2019 Modeling the interplay between the shear layer and leading edge suction during dynamic stall. Phys. Fluids 31, 107104.CrossRefGoogle Scholar
Ekaterinaris, J.A. & Platzer, M.F. 1998 Computational prediction of airfoil dynamic stall. Prog. Aerosp. Sci. 33, 759846.CrossRefGoogle Scholar
Eldredge, J.D. & Jones, A.R. 2019 Leading-edge vortices: mechanics and modeling. Annu. Rev. Fluid Mech. 51, 75104.CrossRefGoogle Scholar
Eljack, E., Soria, J., Elawad, Y. & Ohtake, T. 2021 Simulation and characterization of the laminar separation bubble over a NACA-0012 airfoil as a function of angle of attack. Phys. Rev. Fluids 6, 034701.CrossRefGoogle Scholar
Evans, W.T. & Mort, K.W. 1959 Analysis of computer flow parameters for a set of sudden stalls in low-speed two-dimensional flow. Tech. Note D-85. NASA.Google Scholar
Gerontakos, P. & Lee, T. 2006 Dynamic stall flow control via a trailing-edge flap. AIAA J. 44, 469480.CrossRefGoogle Scholar
Graftieaux, L., Michard, M. & Nathalie, G. 2001 Combining PIV, POD and vortex identification algorithms for the study of unsteady turbulent swirling flows. Meas. Sci. Technol. 12, 14221429.CrossRefGoogle Scholar
Gupta, R. & Ansell, P.J. 2018 Unsteady flow physics of airfoil dynamic stall. AIAA J. 57, 165175.CrossRefGoogle Scholar
He, G., Deparday, J., Siegel, L., Henning, A. & Mulleners, K. 2020 Stall delay and leading-edge suction for a pitching airfoil with trailing-edge flap. AIAA J. 58, 51465155.CrossRefGoogle Scholar
Hirato, Y., Shen, M., Gopalarathnam, A. & Edwards, J.R. 2019 Vortex-sheet representation of leading-edge vortex shedding from finite wings. J. Aircr. 56, 16261640.CrossRefGoogle Scholar
Hirato, Y., Shen, M., Gopalarathnam, A. & Edwards, J.R. 2021 Flow criticality governs leading-edge-vortex initiation on finite wings in unsteady flow. J. Fluid Mech. 910, A1.CrossRefGoogle Scholar
Hou, W., Darakananda, D. & Eldredge, J.D. 2019 Machine-learning-based detection of aerodynamic disturbances using surface pressure measurements. AIAA J. 57, 50795093.CrossRefGoogle Scholar
Huang, Y. & Green, M.A. 2015 Detection and tracking of vortex phenomena using lagrangian coherent structures. Exp. Fluids 56, 147.CrossRefGoogle Scholar
Jones, K.D., & Platzer, M.F. 1998 On the prediction of dynamic stall onset on airfoils in low speed flow. In Unsteady Aerodynamics and Aeroelasticity of Turbomachines, pp. 797–812. KilMer Academic Publishers.CrossRefGoogle Scholar
Kirk, P.B. & Jones, A.R. 2019 Vortex formation on surging aerofoils with application to reverse flow modelling. J. Fluid Mech. 859, 5988.CrossRefGoogle Scholar
Leishman, J.G. & Beddoes, T.S. 1989 A semi-empirical model for dynamic stall. J. Am. Helicopter Soc. 34, 317.Google Scholar
Li, Z.Y., Feng, L.H., Kissing, J., Tropea, C. & Wang, J.J. 2020 Experimental investigation on the leading-edge vortex formation and detachment mechanism of a pitching and plunging plate. J. Fluid Mech. 901, A17.CrossRefGoogle Scholar
Liu, Z., Lai, J.C.S., John, Y. & Tian, F.B. 2017 Discrete vortex method with flow separation corrections for flapping-foil power generators. AIAA J. 55, 410418.CrossRefGoogle Scholar
Mulleners, K. & Raffel, M. 2012 The onset of dynamic stall revisited. Exp. Fluids 52, 779793.CrossRefGoogle Scholar
Mulleners, K. & Raffel, M. 2013 Dynamic stall development. Exp. Fluids 54, 1469.CrossRefGoogle Scholar
Narsipur, S., Gopalarathnam, A. & Edwards, J.R. 2019 Low-order model for prediction of trailing-edge separation in unsteady flow. AIAA J. 57, 191207.CrossRefGoogle Scholar
Narsipur, S., Hosangadi, P., Gopalarathnam, A. & Edwards, J.R. 2020 Variation of leading-edge suction during stall for unsteady aerofoil motions. J. Fluid Mech. 900, A25.CrossRefGoogle Scholar
Ramesh, K., Gopalarathnam, A., Edwards, J.R., Ol, M.V. & Granlund, K. 2013 An unsteady airfoil theory applied to pitching motions validated against experiment and computation. Theor. Comput. Fluid Dyn. 27, 843864.CrossRefGoogle Scholar
Ramesh, K., Gopalarathnam, A., Granlund, K., Ol, M.V. & Edwards, J.R. 2014 Discrete-vortex method with novel shedding criterion for unsteady aerofoil flows with intermittent leading-edge vortex shedding. J. Fluid Mech. 751, 500538.CrossRefGoogle Scholar
Ramesh, K., Granlund, K., Ol, M.V., Gopalarathnam, A. & Edwards, J.R. 2018 Leading-edge flow criticality as a governing factor in leading-edge vortex initiation in unsteady airfoil flows. Theor. Comput. Fluid Dyn. 32, 109136.CrossRefGoogle Scholar
Ramesh, K., Murua, J. & Gopalarathnam, A. 2015 Limit-cycle oscillations in unsteady flows dominated by intermittent leading-edge vortex shedding. J. Fluids Struct. 55, 84105.CrossRefGoogle Scholar
Rezaei, A.S. & Taha, H. 2021 Circulation dynamics of small-amplitude pitching airfoil undergoing laminar-to-turbulent transition. J. Fluids Struct. 100, 103177.CrossRefGoogle Scholar
Ringuette, M.J., Milano, M. & Gharib, M. 2007 Role of the tip vortex in the force generation of low-aspect-ratio normal flat plates. J. Fluid Mech. 581, 453468.CrossRefGoogle Scholar
Samuthira Pandi, J.S. & Mittal, S. 2019 Wake transitions and laminar separation bubble in the flow past an Eppler 61 airfoil. Phys. Fluids 31, 114102.CrossRefGoogle Scholar
Sharma, A. & Visbal, M. 2019 Numerical investigation of the effect of airfoil thickness on onset of dynamic stall. J. Fluid Mech. 870, 870900.CrossRefGoogle Scholar
Taira, K., Brunton, S.L., Dawson, S., Rowley, C.W., Colonius, T., Mckeon, B.J., et al. 2017 Modal analysis of fluid flows: an overview. AIAA J. 55, 40134041.CrossRefGoogle Scholar
Visbal, M.R. 2014 Analysis of the onset of dynamic stall using high-fidelity large-eddy simulations. AIAA Paper 2014-0591.CrossRefGoogle Scholar
Visbal, M.R. & Benton, S.I. 2018 Exploration of high-frequency control of dynamic stall using large-eddy simulations. AIAA J. 56, 29742991.CrossRefGoogle Scholar
Visbal, M.R. & Garmann, D.J. 2018 Analysis of dynamic stall on a pitching airfoil using high-fidelity large-eddy simulations. AIAA J. 56, 4663.CrossRefGoogle Scholar
Wang, S., Ingham, D.B., Ma, L., Pourkashanian, M. & Tao, Z. 2010 Numerical investigations on dynamic stall of low Reynolds number flow around oscillating airfoils. Comput. Fluids 39, 15291541.CrossRefGoogle Scholar
Widmann, A. & Tropea, C. 2015 Parameters influencing vortex growth and detachment on unsteady aerodynamic profiles. J. Fluid Mech. 773, 432459.CrossRefGoogle Scholar
Zhang, J. 2017 Footprints of a flapping wing. J. Fluid Mech. 818, 14.CrossRefGoogle Scholar
Zhou, J., Adrian, R.J., Balachandar, S. & Kendall, T.M. 1999 Mechanisms for generating coherent packets of hairpin vortices in channel flow. J. Fluid Mech. 387, 353396.CrossRefGoogle Scholar