Problem of the interaction of a wedge moving with supersonic velocity when it encounters an interface between two gases

AbstractObservations of the giant irregular galaxy NGC 4449 are being used to study the correlations between the diameter or luminosity and the velocity dispersion of its giant HII regions (GHRs), understanding as GHRs those HII regions with supersonic velocity dispersions. In the central part of this galaxy the HII regions overlap, and also there is a strong, morphologically diffuse emission that permeates the main body of NGC 4449, both effects making difficult the detection, identification and separation of HII regions. We have developed new techniques to solve these problems, obtaining HII regions parameters equivalent to the ones that would be got if the HII regions did not overlap and if the diffuse emission did not exist.

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Interaction of Upstream Flow Distortions With High Number Cascades

Volume 1: Turbomachinery ◽

10.1115/82-gt-137 ◽

1982 ◽

Cited By ~ 1

Author(s):

G. W. Englert

Keyword(s):

Fourier Series ◽

Analytical Study ◽

Wave Length ◽

Double Fourier Series ◽

Supersonic Velocity ◽

Amplitude Wave ◽

Linear Cascade ◽

Spatial Coordinates ◽

Mach Numbers ◽

Upstream Flow

This analytical study models features of the interaction of flow distortions, such as gusts and wakes, with blade rows of advance type fans and compressors having high tip Mach numbers. A typical disturbance is described, at afar upstream location, in three orthogonal spatial coordinates by a double Fourier series. It is convected at supersonic velocity relative to a linear cascade described as an unrolled annulus. Details of interaction of the disturbance with an in-passage shock are discussed. Influences of amplitude, wave length, and phase of the disturbance on lifts and moments of cascade configurations are presented.

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An Improved Apparatus for Supersonic Velocity and Absorption Measurements

Review of Scientific Instruments ◽

10.1063/1.1769988 ◽

1942 ◽

Vol 13 (3) ◽

pp. 122-126 ◽

Cited By ~ 8

Author(s):

D. Telfair ◽

W. H. Pielemeier

Keyword(s):

Supersonic Velocity ◽

Absorption Measurements

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A case of gaseous accretion

Mathematical Proceedings of the Cambridge Philosophical Society ◽

10.1017/s0305004100028656 ◽

1953 ◽

Vol 49 (3) ◽

pp. 486-492 ◽

Cited By ~ 4

Author(s):

K. N. Dodd

Keyword(s):

Mathematical Models ◽

Isothermal Flow ◽

Supersonic Velocity ◽

Gas Velocity ◽

Isothermal Gas

ABSTRACTThe isothermal flow of gas past a gravitating point-sink has been studied for four values of the undisturbed gas velocity, all of which are supersonic. From these studies, estimates have been made of the rates of accretion of an isothermal gas by a star moving with a supersonic velocity. These estimates are of the same order as those obtained by earlier workers who used simpler mathematical models.

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