Advertisement

Rooftop Siting of a Small Wind Turbine Using a Hybrid BEM-CFD Model

  • F. BalduzziEmail author
  • A. Bianchini
  • D. Gentiluomo
  • G. Ferrara
  • L. Ferrari
Conference paper
  • 506 Downloads
Part of the Green Energy and Technology book series (GREEN)

Abstract

The benefits of wind turbine rooftop installations are related to the exploitation both of a higher elevation within the atmospheric boundary layer and of possible local accelerated flows originated by the interaction between the wind and the surrounding landscape. The selection of the proper turbine positioning is however pivotal to ensure maximized energy yields. Although the complete solution of the flow field surrounding the rotors would lead to most accurate results, lower-fidelity models with a more affordable computational cost are still about to be preferable for multivariate optimization analyses. In this study, a set of simulations using a hybrid BEM-CFD model were carried out to optimize the siting of a small HAWT in the rooftop of a suburban building. The parametric study on the urban landscape and the turbine positioning showed that the proposed approach hybrid approach provides interesting prospects in view of more energy-efficient urban installations of wind turbines.

Keywords

Wind turbine Rooftop CFD Built environment Siting 

List of Symbols and Abbreviations

ABL

Atmospheric Boundary Layer

ADM

Actuator Disk Model

BEM

Blade Element Momentum

CFD

Computational Fluid Dynamics

Cµ

Turbulence model constant

Cp

Power coefficient

Cs

Roughness constant

d

Displacement (m)

D

Distance between UB and IB (m)

h

UB height (m)

H

IB height (m)

Ĥ

Mean buildings height (m)

HAWT

Horizontal Axis Wind Turbine

Ks

Sand-grain roughness (m)

k

Turbulent kinetic energy (m2/s2)

IB

Installation Building

L

Buildings width (m)

P

Turbine power (W)

R

Turbine radius (m)

R2

Coefficient of determination

RANS

Reynolds-Averaged Navier-Stokes

TSR

Tip-Speed Ratio

UB

Upwind Building

u*

Friction velocity (m/s)

V

Flow velocity (m/s)

VAWT

Vertical Axis Wind Turbine

VBM

Virtual Blade Model

yp

Height of the ground cells centroid (m)

z0

Roughness length (m)

Greek Letters

γ

Skew angle (deg)

ε

Turbulent kinetic energy dissipation rate (m2/s3)

κ

Von Karman constant

ω

Specific turbulence dissipation rate (s−1)

Notes

Acknowledgements

The activity presented in the paper is part of the research grant assigned to Dr. Francesco Balduzzi by the Fondazione Cassa di Risparmio di Firenze, which is sincerely acknowledged for its invaluable effort is sustaining the university research. Thanks are due to Prof. Ennio Antonio Carnevale of the University of Florence for supporting this activity.

References

  1. 1.
    Ledo, L., Kosasih, P.B., Cooper, P.: Roof mounting site analysis for micro-wind turbines. Renew. Energy 36(5), 1379–1391 (2011)CrossRefGoogle Scholar
  2. 2.
    Abohela, I., Hamza, N., Dudek, S.: Effect of roof shape, wind direction, building height and urban configuration on the energy yield and positioning of roof mounted wind turbines. Renew. Energy 50, 1106–1118 (2013)CrossRefGoogle Scholar
  3. 3.
    Herrmann-Priesnitz, B., Calderón-Muñoz, W.R., LeBoeuf, R.: Effects of urban configuration on the wind energy distribution over a building. J. Renew. Sustain. Energy 7(3), 033106 (2015)CrossRefGoogle Scholar
  4. 4.
    Balduzzi, F., Bianchini, A., Ferrari, L.: Microeolic turbines in the built environment: influence of the installation site on the potential energy yield. Renew. Energy 45, 163–174 (2012)CrossRefGoogle Scholar
  5. 5.
    Balduzzi, F., Bianchini, A., Carnevale, E.A., Ferrari, L., Magnani, S.: Feasibility analysis of a Darrieus vertical-axis wind turbine installation in the rooftop of a building. Appl. Energy 97, 921–929 (2012)CrossRefGoogle Scholar
  6. 6.
    Bianchi, S., Bianchini, A., Ferrara, G., Ferrari, L.: Small wind turbines in the built environment: influence of flow inclination on the potential energy yield. J. Turbomach. 136(4), 041013-041013-8 (2013)Google Scholar
  7. 7.
    Schily, F., Paraschivoiu, M.: CFD Study of a Savonius wind turbine on a rooftop. In: CFDSC, Waterloo, ON (2015)Google Scholar
  8. 8.
    Zanforlin, S., Letizia, S.: Improving the performance of wind turbines in urban environment by integrating the action of a diffuser with the aerodynamics of the rooftops. Energy Procedia 82, 774–781 (2015)CrossRefGoogle Scholar
  9. 9.
    Micallef, D., Sant, T., Ferreira, C.: The influence of a cubic building on a roof mounted wind turbine. In: Science of Making Torque from Wind, TORQUE 2016, Munich (2016)Google Scholar
  10. 10.
    Bianchini, A., Balduzzi, F., Gentiluomo, D., Ferrara, G., Ferrari, L.: Comparative analysis of different numerical techniques to analyze the wake of a wind turbine. In: ASME Turbo Expo 2017, June 26–30, Charlotte, USA (2017)Google Scholar
  11. 11.
    Bianchini, A., Balduzzi, F., Gentiluomo, D., Ferrara, G., Ferrari, L.: Potential of the virtual blade model in the analysis of wind turbine wakes using wind tunnel blind tests. Energy Procedia (2017) (paper in publishing)Google Scholar
  12. 12.
    Mertens, S.: Wind Energy in the Built Environment. Multi-Science, Brentwood (2006)Google Scholar
  13. 13.
    Cebeci, T., Bradshaw, P.: Momentum Transfer in Boundary Layers. Hemisphere Publishing, New York (1977)zbMATHGoogle Scholar
  14. 14.
    Blocken, B., Stathopoulos, T., Carmeliet, J.: CFD simulation of the atmospheric boundary layer: wall function problems. Atmos. Environ. 41(2), 238–252 (2007)CrossRefGoogle Scholar
  15. 15.
    Leitl, B., Shatzmann, M.: Compilation of Experimental Data for Validation of Microscale Dispersion Model. CEDVAL, Meteorological Institute, Hamburg University, Hamburg (1998)Google Scholar
  16. 16.
    Richards, P.J., Hoxey, R.P.: Appropriate boundary conditions for computational wind engineering models using the k-ε turbulence model. J. Wind Eng. Ind. Aerodyn. 46, 145–153 (1993)CrossRefGoogle Scholar
  17. 17.
    Laith, Z., Rajagopalan, R.: Navier-Stokes calculations of rotor-airframe interaction in forward flight. J. Am. Helicopter Soc. 40(2), 57–67 (1995)CrossRefGoogle Scholar
  18. 18.
    Javaherchi Mozafari, A.T.: Numerical modeling of tidal turbines: methodology development and potential physical environmental effects. M.Sc. Thesis in Mechanical Engineering, University of Washington (2010)Google Scholar
  19. 19.
    Burton, T., Sharpe, D., Jenkins, N., Bossanyi, E.: Wind Energy Handbook. Wiley, Oxford (2001)CrossRefGoogle Scholar
  20. 20.
    Cerisola, A.: Numerical analysis of tidal turbines using virtual blade model and single rotating reference frame. Technical report, University of Washington (2012)Google Scholar
  21. 21.
    Du, Z., Selig, M.S.: A 3-D stall-delay model for horizontal axis wind turbines performance prediction. In: ASME Wind Energy Symposium, January 12–15, Reno, Nevada, paper no AIAA-98-0021 (1998)Google Scholar
  22. 22.
    Andersen, B.: Wake behind a wind turbine operating in yaw. M.Sc. thesis, NTNU, Trondheim, Norway (2013)Google Scholar
  23. 23.
    Tominaga, T., Mochida, A., Yoshie, R., Kataoka, H., Nozu, T., Yoshikawa, M., Shirawasa, T.: AIJ guidelines for practical applications of CFD to pedestrian wind environment around buildings. J. Wind Eng. Ind. Aerodyn. 96, 1749–1761 (2008)CrossRefGoogle Scholar
  24. 24.
    Mertens, S.: The energy yield of roof mounted wind turbines. Wind Eng. 27(6), 507–517 (2003)CrossRefGoogle Scholar
  25. 25.
    Ratti, C., Di Sabatino, S., Caton, F., Britter, R., Brown, M.: Analysis of 3-D urban databases with respect to pollution dispersion for a number of European and American cities. Water Air Soil Pollut. 2, 459–469 (2002)CrossRefGoogle Scholar
  26. 26.
    Martin, C.L., Longley, I.D., Dorsey, J.R., Thomas, J.R., Gallagher, M.W., Nemitz, E.: Ultrafine particle fluxes above four major European cities. Atmos. Environ. 43, 4714–4721 (2009)CrossRefGoogle Scholar
  27. 27.
    Engineering Science Data Unit: Strong Winds in the Atmospheric Boundary Layer, Part 1: Mean-Hourly Wind Speeds. ESDU 82026 with Amendment A and B, London (1984)Google Scholar
  28. 28.
    Franke, J., Hirsch, C., Jensen, A.G., Krüs, H.W., Schatzmann, M., Westbury, P.S., Miles, S.D., Wisse, J.A., Wright, N.G.: Recommendations on the use of CFD in wind engineering. In: International Conference on Urban Wind Engineering and Building Aerodynamics, von Karman Institute, Sint-Genesius-Rode, Belgium (2004)Google Scholar
  29. 29.
    Franke, J., Hellsten, A., Schlünzen, H., Carissimo, B.: Best Practice Guideline for the CFD Simulation of Flows in the Urban Environment. COST Office, Brussels (2007)Google Scholar
  30. 30.
    Mandel, J.: The Statistical Analysis of Experimental Data. Dover Publications, New York (1984)Google Scholar

Copyright information

© Springer International Publishing AG 2018

Authors and Affiliations

  • F. Balduzzi
    • 1
    Email author
  • A. Bianchini
    • 1
  • D. Gentiluomo
    • 1
  • G. Ferrara
    • 1
  • L. Ferrari
    • 2
  1. 1.Department of Industrial Engineering (DIEF)Università degli Studi di FirenzeFlorenceItaly
  2. 2.Department of Energy, Systems, Territory and Construction Engineering (DESTEC)University of PisaPisaItaly

Personalised recommendations