TURBULENT FLOW IN VIBRATED BED OF POWDER: NEW TARGET TO INVESTIGATE TURBULENT FLOW

The flow patterns in the vibrated bed of powder are investigated numerically in two dimensions. They turn out to exhibit turbulent flow like that observed in fully developed turbulence. The power spectrum of their flow lines has k−5/3 power, where k is the wave number. Since the numerical investigation of powder requires very few computational resources, it provides us with a new tool to study turbulence easily.

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The Present State of the Turbulence Problem

Journal of Applied Mechanics ◽

10.1115/1.4012170 ◽

1933 ◽

Vol 1 (1) ◽

pp. 19-28

Author(s):

Walter Tollmien

Keyword(s):

Turbulent Flow ◽

Flat Plate ◽

Skin Friction ◽

Turbulence Theory ◽

Shearing Stress ◽

Mean Velocity ◽

Fully Developed Turbulence ◽

Developed Turbulence ◽

The Mean ◽

Real Goal

Abstract In this survey the author first describes certain types of turbulent flow, following which he deals successively with the production of turbulent motion; the instability of the laminar motion; fully developed turbulence; momentum interchange and mixing lengths; and relations between the shearing stress at the wall and the mean velocity distributions. Finally he takes up the calculation of skin friction for simple cases of fully developed turbulence, especially for that of the flat plate. Although the methods outlined have often led to practically useful results, it is the author’s belief that they should be considered only as advances toward the real goal of the turbulence theory. The derivation of turbulence phenomena from the hydrodynamical equations will, in his opinion, be possible only by the application of statistical methods.

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On the static pressure in fully-developed turbulent flow

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1936.0121 ◽

1936 ◽

Vol 155 (886) ◽

pp. 576-596 ◽

Cited By ~ 15

Keyword(s):

Turbulent Flow ◽

Static Pressure ◽

Cylindrical Body ◽

Pressure Tube ◽

Good Design ◽

Fully Developed Turbulence ◽

Developed Turbulence ◽

Total Head ◽

Pressure Tubes ◽

Fully Developed Turbulent Flow

1-The present investigation has a twofold purpose: first, to obtain a measure of the effect of fully-developed turbulence on the reading of a static pressure tube; and second, to obtain information on the distribution of static pressure in the fully-developed turbulent flow in a pipe and in the wake behind a long cylindrical body. The work arose from a paper by DR. Goldstein on the measurement of total head and static pressure in a turbulent stream. 2-Static Pressure Tubes A static pressure tube of good design is one for which small local disturbances at the nose, arising from the introduction of the tube into the stream, have time to die away before the static holes are reached. The reading of such a tube in a steady stream depends on the shape of the nose, the distance of the holes behind the nose, and the distance of the supporting stem behind the holes. When the static holes are at least 6 tube-diameters behind the head, and the stem a least 15 stem-diameters downstream from the holes, the reading of the tube is independent, within wide limits, of the shape of the head.

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