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No.9 (1975/03) >

 
Title :擬似衝撃波に関する研究
Title alternative :Investigation of Pseudo-shock Waves
Authors :永井, 実
Authors alternative :Nagai, Minoru
Issue Date :1-Mar-1975
Abstract :In the high-speed flow in duct, the shock wave which has occured when the supersonic flow was decelarated to the subsonic flow interacts with the wall boundary layer. Then, the length of the compression region is lengthened and becomes some times of the duct length. Such a shock wave is called pseudo-shock wave being distinguished from the normal shock wave. It is thought that the interaction problems of shock waves and boundary layers have been learned mainly from the view point of the outer flow aerodynamics such as aeronautics and there are few investigations from the view point of the inner flow aerodynamics, so there remains many unknown points about the behaviour and the structure of pseudoshock waves in ducts. In this paper, pseudo-shock waves in ducts were investigated experimentally and theoretically. Chapter 1 of this paper gives a review of the investigations of shock-boundary layer interactions and pseudo-shock waves. In chapters 2 and 3, the behaviour of pseudo-shock waves in fairly long ducts and at the portion of sudden enlargement of duct area were learned and the results were explained by the theory of one-dimensional adiabatic friction flow. Further, it was reported that there was the history in the behaviour of pseudo-shock at the sudden enlargement portion and that the oscillation of pseudo-shock wave gave great influencies to the duct wall locally. In chapter 4, the structure of pseudo-shock waves of various inflow Mach numbers were ovserved and a diffusion model of pseudo-shock wave was presented which was obtained by reforming Crocco's shockless model. This model could explain the length of pseudo-shock and the pressure distribution along the duct in the region of pseudo-shock wave, and closer agreements between the theory and the experimental data by author and other researchers were obtained. In chapter 5, it was cleared that the pseudo-shock wave in a straight duct was not steady but always oscillating to and fro in the duct, and theoretical considerations of causes and frequencies of the oscillations were presented. Chapter 6 gives the conclusions of this investigation. Finally in the appendix, the basic theories of the high speed aerodynamics in ducts which were used in this paper were summarized.
Type Local :紀要論文
ISSN :0387-429X
Publisher :琉球大学理工学部
URI :http://hdl.handle.net/20.500.12000/26356
Citation :琉球大学理工学部紀要. 工学篇 = Bulletin of Science & Engineering Division, University of the Ryukyus. Engineering no.9 p.29 -80
Appears in Collections:No.9 (1975/03)

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