Tohoku University Graduate School
Institute of Fluid Science, Tohoku University
Institute of Fluid Science, Tohoku University
出版者
航空宇宙技術研究所
出版者(英)
National Aerospace Laboratory (NAL)
雑誌名
航空宇宙技術研究所特別資料: 境界層遷移の解明と制御研究会講演論文集 第29回・第30回
雑誌名(英)
Special Publication of National Aerospace Laboratory: Proceedings of the 29th and 30th NAL Workshops on Investigation and Control of Boundary-Layer Transition
巻
56
ページ
65 - 68
発行年
2002-12
抄録(英)
The boundary layer along a wind-tunnel contraction nozzle is investigated in detail using hotwire anemometry and flow visualization method. It is found that Gortler vortex system exists and develops in the concave wall region of the contraction nozzle. In spite of the flow acceleration by the contraction the disturbance enhanced by the Gortler vortex system travels down even to the test section. It was found that this disturbed region at the test section is more than 35 percent of the cross-sectional area. This result shows the effects of the Gortler vortex system should be taken into consideration in designing a wind-tunnel contraction nozzle. When acceleration parameter is large enough to laminarize the boundary layer, the boundary layer at the outlet of the contraction nozzle becomes to be laminar. Acceleration parameter is also important to design contraction nozzle.