Czasopismo
2011
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Vol. 16, no 2
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345-358
Tytuł artykułu
Autorzy
Wybrane pełne teksty z tego czasopisma
Warianty tytułu
Języki publikacji
Abstrakty
The complex flow in the rotor root area is analyzed by means of the boundary layer approach. The approach involves a radial angular velocity (Ekman) boundary-layer on the rotor disk rotating with an angular velocity smaller than that of the fluid, and the circumferential velocity boundary-layer developing on blades. The first explains the smaller adverse pressure gradient at the leading-edge of blades by a vortex-induced sucking effect, and the other shows the contribution of Coriolis force to the closed separation behavior on the suction side of the inboard blade sections, that explains the stall-delay phenomenon. Three-dimensional incompressible steady momentum integral boundary layer equations are used to analyze the leading-edge separation bubble on a rotating blade, including the effect of enhanced rotation at strong winds. The stall-delay phenomenon is described as a three contribution process: vortex-induced sucking effect by an Ekman layer type boundary-layer followed by Coriolis force, which acts in the chordwise direction as a favorable pressure gradient, and centrifugal forces producing a spanwise pumping effect. It appears that the first two contributions play the primary role for the rise of the inboard stall-delay and the centrifugal pumping effect is much less important than generally was supposed before.
Rocznik
Tom
Strony
345-358
Opis fizyczny
Bibliogr. 18 poz., wykr.
Twórcy
autor
autor
- "Gh. Mihoc-C. Iacob" Institute of Mathematical Statistics and Applied Mathematics of the Romanian Academy P.O. Box 1-24, RO-70700, Bucharest, ROMANIA, v_cardos@yahoo.ca
Bibliografia
- Banks W.H. and Gadd G.E. (1963): Delaying effects of rotation on laminar separation. ( AIAA Journal, vol.1, No.4, pp.941-942.
- Carcangiu C.E., Sörensen J.N., Cambuli F. and Mandas N. (2007): CFD-RANS analysis of the rotational effects on the boundary layer of wind turbine blades. The Science of Making Torque from Wind. ( Journal of Physics: Conference Series, vol.75, 012034.
- Chaviaropoulos P.K. and Hansen M.O.L. (2000): Investigating three-dimensional and rotational effects on wind turbine blades by means of a quasi-3D Navier-Stokes solver. ( Journal of Fluids Engineering, vol.122, pp.330-336.
- Du Z. and Seling M.S. (2000): The effect of rotation on the boundary layer of a wind turbine blade. ( Renewable Energy, vol.20, pp.167-181.
- Dumitrescu H. and Cardoş V. (2004): Rotational effects on the Boundary-Layer flow in wind turbines. ( AIAA Journal, vol.42, No.2, pp.408-411.
- Dumitrescu H. and Cardoş V. (2007a): Prediction of the three-dimensional separation on a rotating blade. ( Int. J. of Applied Mechanics and Engineering, vol.12, No.4, pp.941-950.
- Dumitrescu H. and Cardoş V. (2007b): Modeling of inboard stall delay due to rotation. The Science of Making Torque from Wind. ( Journal of Physics: Conference Series, vol.75, 012022.
- Fogarty L.E. and Sears W.R. (1950): Potential flow around a rotating advancing cylinder blade. ( Journal Aeronautical Sciences (reader Forum), vol.17, No.10, pp.599-601.
- Himmellskamp H. (1945): Profile investigation on a rotating airscrew. - Technical Report PhD Disertation Göttingen Germany.
- Mager A. (1952): Generalization of the boundary layer momentum integral equations to three dimensional flows including those of rotating systems. - NACA Report 1067.
- Rauch J., Krämer T. and Heinzelmann B. (2007): 3-D numerical simulation and evaluation of the air flow through wind turbine rotors with focus on the hub area. - Berlin: in Peinke J, Schaumann P, Barth S. Wind Energy, Springer-Verlag, pp.227-230.
- Schlichting H. (1968): Boundary-Layer Theory. - New York: Mc. Graw-Hill Book Company.
- Schlichting H. and Gersten K. (2000): Boundary-Layer Theory. - Berlin: Springer-Verlag, pp.589.
- Shen W.Z. and Sörensen J.N. (1999): Quasi-3D Navier-Stokes model for a rotating airfoil. ( Journal of Computational Physics, vol.150, pp.518-548.
- Snel H., Houwnik and Bosschers R. J. (1994): Sectional prediction of lift coefficients on rotating wind turbine blades in stall. ( Netherlands Energy Research Foundation, ECN Report, ECN-C-93-052.
- Tangler R. (2004): Insight into wind turbine stall and post-stall aerodynamics. ( Wind Energy, vol.7, No.3, pp.247-261.
- Toren M. and Solan A. (1979): Laminar boundary layer on a finite disk in a rotating compressible isothermal flow. ( Journal of Fluids Engineering, vol.101, pp.166-172.
- Van Rooij R.P.J.O.M. and Arens E.A. (2007): Analysis of the experimental and computational flow characteristics with respect to the augmented lift phenomenon caused by blade rotation. ( The Science of Making Torque from Wind. Journal of Physics: Conference Series, vol.75, 012021.
Typ dokumentu
Bibliografia
Identyfikatory
Identyfikator YADDA
bwmeta1.element.baztech-article-BPZ5-0017-0002