1 / 12

EAWE PhD-Seminar, Risø 4. October

EAWE PhD-Seminar, Risø 4. October. PhD-Student Brian Riget Broe Semi-Empirical modeling of Aerodynamical Noise Risø National Laboratory Frederiksborgvej 399 4000 Roskilde, Denmark Aeroacoustics and Fluctuating Lift. Sources of aerodynamic noise. From Moriarty (2003).

armen
Download Presentation

EAWE PhD-Seminar, Risø 4. October

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. EAWE PhD-Seminar, Risø 4. October PhD-Student Brian Riget Broe Semi-Empirical modeling of Aerodynamical Noise Risø National Laboratory Frederiksborgvej 399 4000 Roskilde, Denmark Aeroacoustics and Fluctuating Lift

  2. Sources of aerodynamic noise From Moriarty (2003) EAWE PhD-Seminar, Risø 4.-5. October, 2006

  3. Modeling the inflow noise Model by Amiet (1975) The power spectrum of the surface pressure Task: Find the Fluctuating lift for an arbitrary profile EAWE PhD-Seminar, Risø 4.-5. October, 2006

  4. 2-D gust on a flat plate Sears (1941) and Graham (1971) EAWE PhD-Seminar, Risø 4.-5. October, 2006

  5. 2-D gust on a flat plate, Results Sears (1941) 1-D A sinusoidal gust impinging on a semi-infinite flat plate. k is the wave vector which is in the plane of the flat plate. The wave vector has the component  in the x-direction and  in the y-direction. The wave front hits the edge of the plate in an angle. For the 1-D case  is zero. EAWE PhD-Seminar, Risø 4.-5. October, 2006

  6. Measured surface pressure (1) Measurements by Mish et al. (2006) for a NACA 0015 profile EAWE PhD-Seminar, Risø 4.-5. October, 2006

  7. Measured surface pressure (2) Measurements by Mish et al. (2006) for a NACA 0015 profile EAWE PhD-Seminar, Risø 4.-5. October, 2006

  8. 2-D gust on a profile A sinusoidal gust impinging on a Joukowsky aerofoil. k is the wave vector. The wave vector has the component  in the x-direction and  in the z-direction. For the 1-D case  is zero. Goldstein and Atassi (1976) EAWE PhD-Seminar, Risø 4.-5. October, 2006

  9. Joint lift response of angle attack and camber EAWE PhD-Seminar, Risø 4.-5. October, 2006

  10. Lift response due to thickness EAWE PhD-Seminar, Risø 4.-5. October, 2006

  11. Summary • A function for the fluctuating lift needs to be found for an arbitrary profile • Measurements of the surface pressure is going to be made by Risø for a Risø profile • Work on model by linearized theory to find the fluctuating lift due thickness EAWE PhD-Seminar, Risø 4.-5. October, 2006

  12. References Listed in order of appearence • P. Moriarty and P. Migliore, Semi-Empirical Aeroacoustic Noise Prediction Code for Wind Tubines, 2003, NREL/TP-500-34478. • R. K. Amiet, Acoustic Radiation From An Airfoil In A Turbulent Stream, 1975, J. Sound and Vibr., 41(4), 407-420. • P. F. Mish and W. J. Devenport, An experimental investigation of unsteady surface pressure on an airfoil in turbulence-Part 1: Effects of mean loading, 2006a, J. Sound and Vibr., 296, 417-446. • W. R. Sears, Some Aspects of Non-Stationary Airfoil Theory and Its Practical Application, 1941, J. of the Aeronatical Sc., Vol. 8, No. 3, 104-108. • J. M. R. Graham, Lifting Surface Theory for the Problem of an Arbitrarily Yawed Sinusoidal Gust Incident on a Thin Aerofoil in Imcompressible Flow, 1971, The Aeronautical Quart., 182-198. • M. E. Goldstein and H. Atassi, A complete second-order theory for the unsteady flow about an airfoil due to a period gust, 1976, J. Fluid Mech., vol. 74, part 4, 741-765. • H. M. Atassi, The Sears problem for a lifting airfoil revisited – new results, J. Fluid Mech., 1984, vol. 141, 109-122. EAWE PhD-Seminar, Risø 4.-5. October, 2006

More Related