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
Part of the Green Energy and Technology book series (GREEN)


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.


Wind turbine Rooftop CFD Built environment Siting 

List of Symbols and Abbreviations


Atmospheric Boundary Layer


Actuator Disk Model


Blade Element Momentum


Computational Fluid Dynamics


Turbulence model constant


Power coefficient


Roughness constant


Displacement (m)


Distance between UB and IB (m)


UB height (m)


IB height (m)


Mean buildings height (m)


Horizontal Axis Wind Turbine


Sand-grain roughness (m)


Turbulent kinetic energy (m2/s2)


Installation Building


Buildings width (m)


Turbine power (W)


Turbine radius (m)


Coefficient of determination


Reynolds-Averaged Navier-Stokes


Tip-Speed Ratio


Upwind Building


Friction velocity (m/s)


Flow velocity (m/s)


Vertical Axis Wind Turbine


Virtual Blade Model


Height of the ground cells centroid (m)


Roughness length (m)

Greek Letters


Skew angle (deg)


Turbulent kinetic energy dissipation rate (m2/s3)


Von Karman constant


Specific turbulence dissipation rate (s−1)



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.


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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

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