Skip to main content

Advertisement

Log in

Dynamic stall on a pitching and surging airfoil

  • Research Article
  • Published:
Experiments in Fluids Aims and scope Submit manuscript

Abstract

Vertical axis wind turbine blades undergo dynamic stall due to the large angle of attack variation they experience during a turbine rotation. The flow over a single blade was modeled using a sinusoidally pitching and surging airfoil in a non-rotating frame with a constant freestream flow at a mean chord Reynolds number of \({10^5}\). Two-dimensional, time-resolved velocity fields were acquired using particle image velocimetry. Vorticity contours were used to visualize shear layer and vortex activity. A low-order model of dynamic stall was developed using dynamic mode decomposition, from which primary and secondary dynamic separation modes were identified. The interaction between these two modes was able to capture the physics of dynamic stall and as such can be extended to other turbine configurations and problems in unsteady aerodynamics. Results from the linear pitch/surge frame are extrapolated to the rotating VAWT frame to investigate the behavior of identified flow structures.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12
Fig. 13
Fig. 14
Fig. 15
Fig. 16
Fig. 17
Fig. 18
Fig. 19

Similar content being viewed by others

Abbreviations

t :

Time (s)

\(\alpha\) :

Angle of attack (°)

\(\theta\) :

Turbine rotation angle (°)

\(Re_{\rm c}\) :

Chord Reynolds number (\(\frac{Uc}{\nu }\))

\(U_\infty\) :

Wind speed (\(\hbox {m s}^{-1}\))

U :

Effective velocity (\(\hbox {m s}^{-1}\))

\(\bar{U}\) :

Average velocity in experiment (tunnel velocity) (\(\hbox {m s}^{-1}\))

\(\chi\) :

Spanwise vorticity (\(\hbox {s}^{-1}\))

\(\eta\) :

Tip speed ratio (\(\frac{\omega R}{U_\infty }\))

\(\omega\) :

Turbine frequency (\(\hbox {rad s}^{-1}\))

\(\varOmega\) :

Pitch/surge frequency (\(\hbox {rad s}^{-1}\))

R :

Turbine radius (m)

Ro :

Rossby number (\(\frac{U_\infty }{2c \omega }\))

c :

Chord length (cm)

\(\nu\) :

Kinematic viscosity (\(\hbox {m}^2\hbox { s}^{-1}\))

\(\lambda\) :

Transformed DMD eigenvalues (\(\hbox {rad s}^{-1}\))

k :

Reduced frequency (\(\frac{\varOmega c}{2 \bar{U}}\))

\(\varGamma _1\) :

Vortex center criteria

\(\varGamma _2\) :

Vortex boundary criteria

\(x,\, u\) :

Streamwise coordinate [c], streamwise velocity (\(\hbox {m s}^{-1}\))

\(y,\, v\) :

Cross-stream coordinate [c], cross-stream velocity (\(\hbox {m s}^{-1}\))

z :

Spanwise coordinate (c)

xl :

Leading edge position (c)

i :

Imaginary component

r :

Real component

j :

Variable index

\(\pm\) :

Pitch up (+) and down (−)

References

  • Baik YS, Bernal LP, Granlund K, Ol MV (2012) Unsteady force generation and vortex dynamics of pitching and plunging aerofoils. J Fluid Mech 709:37–68

    Article  MathSciNet  MATH  Google Scholar 

  • Brent S (2009) AWEA standard update

  • Carr L, McAlister K, McCroskey W (1977) Analysis of the development of dynamic stall based on oscillating airfoil experiments. Technical Report January, NASA

  • Carr LW (1988) Progress in analysis and prediction of dynamic stall. J Aircr 25(1):6–17

    Article  Google Scholar 

  • Chakraborty P, Balachandar S, Adrian RJ (2005) On the relationships between local vortex identification schemes. J Fluid Mech 535:189–214

    Article  MathSciNet  MATH  Google Scholar 

  • Chen KK, Tu JH, Rowley CW (2012) Variants of dynamic mode decomposition: boundary condition, Koopman, and Fourier analyses. J Nonlinear Sci 22(6):887–915

    Article  MathSciNet  MATH  Google Scholar 

  • Choi J, Colonius T, Williams DR (2015) Surging and plunging oscillations of an airfoil at low Reynolds number. J Fluid Mech 763:237–253

    Article  Google Scholar 

  • Dabiri JO (2011) Potential order-of-magnitude enhancement of wind farm power density via counter-rotating vertical-axis wind turbine arrays. J Renew Sustain Energy 3(4)

  • Gerakopulos R (2010) Aerodynamic characterization of a NACA 0018 airfoil at low Reynolds numbers. In: 40th AIAA fluid dynamics conference, July. Chicago, IL

  • Graftieaux L (2001) Combining PIV, POD and vortex identification algorithms for the study of unsteady turbulent swirling flows. Meas Sci 1422

  • Greenblatt D, Harav AB, Mueller-Vahl H (2013) Mechanism of dynamic stall control on a vertical axis wind turbine. 51st AIAA aerospace sciences meeting

  • Hau E (2013) Wind turbines: fundamentals, technologies, application, economics. Springer, Berlin

    Book  Google Scholar 

  • Islam M, Ting DSK, Fartaj A (2007) Desirable airfoil features for smaller-capacity straight-bladed VAWT. Wind Eng 31(3):165–196

    Article  Google Scholar 

  • Jones AR, Babinsky H (2010) Unsteady lift generation on rotating wings at low Reynolds number. J Aircr 47(3):1013–1021

    Article  Google Scholar 

  • Kinzel M, Mulligan Q, Dabiri JO (2012) Energy exchange in an array of vertical-axis wind turbines. J Turbul 13(38):1–13

    Google Scholar 

  • Mulleners K, Raffel M (2012) The onset of dynamic stall revisited. Exp Fluids 52(3):779–793

    Article  Google Scholar 

  • Mulleners K, Raffel M (2013) Dynamic stall development. Exp Fluids 54(2):1469–1477

    Article  Google Scholar 

  • Müller-Vahl HF, Strangfeld C, Nayeri CN, Paschereit CO, Greenblatt D (2015) Control of thick airfoil, deep dynamic stall using steady blowing. AIAA J 53(2):277–295

    Article  Google Scholar 

  • Prangemeier T, Rival D, Tropea C (2010) The manipulation of trailing-edge vortices for an airfoil in plunging motion. J Fluids Struct 26(2):193–204

    Article  Google Scholar 

  • Rowley CW, Mezić I, Bagheri S, Schlatter P, Henningson DS (2009) Spectral analysis of nonlinear flows. J Fluid Mech 641:115–127

    Article  MathSciNet  MATH  Google Scholar 

  • Schmid PJ (2010) Dynamic mode decomposition of numerical and experimental data. J Fluid Mech 656:5–28

    Article  MathSciNet  MATH  Google Scholar 

  • Simão Ferreira C, Bijl H, van Bussel G, van Kuik G (2007a) Simulating dynamic stall in a 2D VAWT: Modeling strategy, verification and validation with particle image velocimetry data. J Phys Conf Ser 73

  • Simão Ferreira C, van Bussel G, Scarano F, van Kuik G (2007b) 2D PIV visualization of dynamic stall on a vertical axis wind turbine. In: 45th AIAA Aerospace science meeting

  • Simão Ferreira C, van Kuik G, van Bussel G, Scarano F (2009) Visualization by PIV of dynamic stall on a vertical axis wind turbine. Exp Fluids 46(1):97–108

    Article  Google Scholar 

  • Simão Ferreira CJ, Van Zuijlen A, Bijl H, van Bussel G, van Kuik G (2010) Simulating dynamic stall in a two-dimensional vertical axis wind turbine: verification and validation with particle image velocimetry data. Wind Energy 13:1–17

    Article  Google Scholar 

  • Tsai HC, Colonius T (2014) Coriolis effect on dynamic stall in vertical axis wind turbine at moderate Reynolds number. In: 32nd AIAA applied aerodynamics conference, Atlanta, GA

  • US Energy Information Administration (2012) Electric power monthly. Technical Report DOE/EIA-0226, US energy information administration

  • Windspire (2013) Standard wind unit 1.2kw. Accessed 11/2013

Download references

Acknowledgments

This work was supported by the Gordon and Betty Moore Foundation through grant GBMF#2645 to the California Institute of Technology. The authors thank Professor Peter Schmid for his assistance in implementing the dynamic mode decomposition algorithm, Professor Morteza Gharib for the use of the free surface water channel facility, Hsieh-Chen Tsai and Professor Tim Colonius for discussion on the Coriolis effect and Professor John Dabiri for his insight from VAWT field research.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Reeve Dunne.

Ethics declarations

Conflict of interest

The authors declare that they have no conflict of interest.

Additional information

This article belongs to a Topical Collection of articles entitled Extreme Flow Workshop 2014. Guest editors: I. Marusic and B. J. McKeon.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Dunne, R., McKeon, B.J. Dynamic stall on a pitching and surging airfoil. Exp Fluids 56, 157 (2015). https://doi.org/10.1007/s00348-015-2028-1

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1007/s00348-015-2028-1

Keywords

Navigation