Aerospace Research and Development Directorate, Japan Aerospace Exploration Agency (JAXA)
Aerospace Research and Development Directorate, Japan Aerospace Exploration Agency (JAXA)
出版者
宇宙航空研究開発機構
出版者(英)
Japan Aerospace Exploration Agency (JAXA)
雑誌名
宇宙航空研究開発機構特別資料: 「境界層遷移の解明と制御」研究会講演論文集(第43回・第44回)
雑誌名(英)
JAXA Special Publication: Proceedings of the 43rd and 44th JAXA Workshops on "Investigation and Control of Boundar-Layer Transition"
43rd JAXA Workshops on "Investigation and Control of Boundar-Layer Transition" (October 2-3, 2008) ; 44th JAXA Workshops on "Investigation and Control of Boundar-Layer Transition" (March 26-27, 2009)
抄録(英)
The compressible flows around 2-D airfoils are simulated by using a high-order numerical scheme. In this study, the generation of trailing-edge noise is directly reproduced as the fluctuation in pressure field. Two types of airfoils are investigated: NACA0012 and NACA0006. The obtained results on the vortex-shedding frequencies and the growth rate of velocity fluctuation confirm that the tone noise frequency is determined by the wake instability in both cases. The dipole sound scattered by the acoustically non-compact airfoils shows multiple lobes in the far-field directivity. By imposing non-zero angle of attack, very weak instability waves has little effects on the development of Karman vortex shedding in the present calculation.
内容記述
形態: カラー図版あり
内容記述(英)
Physical characteristics: Original contains color illustrations