著者

城武 雅 郭 東潤 李家 賢一 砂田 保人

出版者

一般社団法人 日本航空宇宙学会

雑誌

日本航空宇宙学会論文集 = Journal of the Japan Society for Aeronautical and Space Sciences (ISSN:13446460)

巻号頁・発行日

vol.54, no.627, pp.175-180, 2006-04-05

参考文献数

10

被引用文献数

1 1

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Wind tunnel tests were conducted to investigate static roll characteristics of an SST model at high angles of attack. The Reynolds number based on the mean aerodynamic chord was 6.2&times;10<SUP>4</SUP>. Normal force and rolling moment measurements have been done at different roll angles for the cranked arrow wing SST model. Smoke visualizations and Particle Image Velocimetry (PIV) measurements were also performed. Force measurement results were compared both with flow visualization pictures and with PIV measurement results. It was shown that the vortex breakdown has strong influences on the static roll characteristics of the cranked arrow wing.

著者

秋山 皓平 手塚 亜聖 砂田 保人 李家 賢一

出版者

一般社団法人 日本航空宇宙学会

雑誌

日本航空宇宙学会論文集 (ISSN:13446460)

巻号頁・発行日

vol.57, no.671, pp.476-485, 2009 (Released:2009-12-14)

参考文献数

15

被引用文献数

1

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This paper investigates wing aerodynamic characteristics used for bi-plane micro-air vehicles. Surface pressure distributions of two-dimensional biplane airfoils (4% cambered-plate airfoil) were measured at a chord Reynolds number of 6.4 × 104. Lift characteristics of three-dimensional biplane rectangular wings (aspect ratio of 3) were also measured at the same Reynolds number. It was indicated that the behaviors of laminar separation bubble formed both on the upper and lower airfoils/wings affects their lift characteristics. Bi-plane wings with positive stagger, i.e. protruded upper wing indicated higher maximum lift coefficient. This is caused by different behaviors of laminar separation bubble formed on the wing.

著者

手塚 亜聖 砂田 保人 李家 賢一

出版者

一般社団法人 日本航空宇宙学会

雑誌

日本航空宇宙学会論文集 = Journal of the Japan Society for Aeronautical and Space Sciences (ISSN:13446460)

巻号頁・発行日

vol.57, no.665, pp.258-265, 2009-06-05

参考文献数

20

被引用文献数

5

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In the Reynolds number region lower than approximately 1.0 × 105, which corresponds to the Reynolds number region of a Micro Air Vehicle, thinner and sharper leading edge airfoil performs better than thicker and blunter one. This research focuses on the difference in flowfields which are clarified by means of streamline calculation and surface pressure distribution measurement. Numerical studies were performed to the blunt type NACA0012 airfoil and both numerical and experimental studies were performed to the thinner type 4% cambered-plate airfoil. The performance of the NACA0012 airfoil is deteriorated with decreasing Reynolds number, whereas that of the 4% circular arc cambered-plate airfoil is not affected. The deterioration of the NACA0012 airfoil performance is mainly due to the laminar boundary layer separation near the trailing edge; such phenomena are not essential to the performance in the cambered-plate airfoil results. This paper also demonstrates that the flow separation at the trailing edge can be estimated from the temporal amplification factor of the oscillatory mode which is calculated by the global linear stability analysis.