登入選單

返回Google圖書搜尋

Mixed Problems for Higher Order Hyperbolic Equations

Shmuel Agmon

出版	Hebrew University, 1962
URL	http://books.google.com.hk/books?id=s0aqNwAACAAJ&hl=&source=gbs_api

註釋

DESCRIPTORS: *Boundary layer, *Jets, Fluid flow, Reynolds number, Laminar boundary layer, Frequency, Flu ter, Excitation, Noz zles, Wave characteristics, Stability, Vis cosity, Vortices. An attempt is made to explain the development of vortices in a separated boundary layer by investigating the axisymmetrical jet downstream of a special nozzle. According to stability theory, a shear profile of finite thickness is unstable against wavy disturbances of certain frequencies and wavelengths. If such wavy disturbances are present in the shear layer, it rolls up into discrete vortices according to Rosenhead's analysis. It is found that viscosity, though responsible for the formation of a shear layer, plays no significant role in the process of rolling up at high Reynolds numbers. The frequency of the natural fluctuations and the relation between frequency and wavelength for artificial excita ion have been measured; the re ults are in good agreement with the theory. (Author).