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No. 50 (1995/09) >

 
Title :はく離・再付着流れのアクティブ制御
Title alternative :Active Control in a Reattaching Separated Flow Field
Authors :照屋, 功
山里, 栄昭
伊良部, 邦夫
甲斐, 伸太郎
高屋, 英司
Authors alternative :Teruya, Isao
Yamazato, Eisho
Irabu, Kunio
Kai, Shintarou
Takaya, Eiji
Issue Date :Sep-1995
Abstract :The process of the separated shear layer and the reattachment is a key feature of many engineering flow problems. Controlling reattachment of a turbulent shear layer is an important process in wide variety of engineering systems. In this paper we investigated an active control using the rotating rod placed near the step inlet. The purpose of the study was to investigate the effect of the reattachment length and the pressure recovery on the excitation by the rotating rod in the flow field. The results are as follows, (1)The excitation of the shear layer by rotating the rod enhances the growth of the separated shear layer and increases the entrainment. Thus the reattachment length is decreased. (2)When the reattachment length is normalized by the width of reattachment region, the data are collapsed without the influence of the disturbance. In other words, flow field in the reattachment region is unchanged even if the disturbance is introduced into the flow field in the reattachment region. (3)The reattachment length also decreases for the circular rod by the rotation of the rod and counter rotation of the rod is more effective than the positive rotation. (4)In the case of rectangular rod rotation, the reattachment length is reduced a maximum of 33 percent and the most effectiveness is shown at 2000rpm. The degree of the disturbance and the frequency are considered to be the factors that decrease the reattachment length. (5)By controlling the flow field with the rod rotation, the decrease of the pressure recovery is comparatively small, so the fluid loss is small.
Type Local :紀要論文
ISSN :0389-102X
Publisher :琉球大学工学部
URI :http://hdl.handle.net/20.500.12000/1995
Citation :琉球大学工学部紀要 no.50 p.35 -43
Appears in Collections:No. 50 (1995/09)

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