翼型における空気吸込み並びに逸流現象
1960 年 1960 巻 106 号 p. a9-a17
詳細
1960 年 1960 巻 106 号 p. a9-a17
NACA 4112 and ogival section (thickness 12%) were held stationary in an open flume containing streaming water. The air drawing and flow separation phenomena were observed and the pressure distribution were measured at several different submergence depth, speed and angle of attack.
In § 2, the observed phenomena were descripted for the inception of air-drawing, occurrence of flow separation and form of cavity.
In§3, the necessary and adequate condition is considered for occurrence of flow separation due to the air-drawinp;, and the surface tension and stalling is enumerated.
In § 4, the effect of the flow separation on the pressure distribution, lift and drag of the hydrofoil section is examined, and also comparison is made with Greens discontinuous flow theory.
In § 5. the scale effect on the flow separation due to air-drawing is examined and the critical Weber number is determined for the NACA 4412 and ogival section.
In § 6, the criterion is proposed for the occurrence of flow separation and the concrete example is shown.
