Bleed flow structure in the wake region of finite array of cylinders acting as an alternative supporting structure for foundation

Urban stormwater is an important environmental problem, especially for metropolitans worldwide. The most important issue behind this problem is the need to find green infrastructure solutions, which provide water treatment and retention. Floating treatment wetlands, which are porous patches that continue down from the free-surface with a gap between the patch and bed, are innovative instruments for nutrient management in lakes, ponds, and slow-flowing waters. Suspended cylindrical vegetation patches in open channels affect the flow dramatically, which causes a deviation from the logarithmic law. This study considered the velocity measurements along the flow depth, at the axis of the patch, and at the near-wake region of the canopy, for different submerged ratios with different patch porosities. The results of this experimental study provide a comprehensive picture of the effects of different submergence ratios and different porosities on the flow field at the near-wake region of the suspended vegetation patch. The flow field was described with velocity and turbulence distributions along the axis of the patch, both upstream and downstream of the vegetation patch. Mainly, it was found that suspended porous canopy patches with a certain range of densities (SVF20 and SVF36 corresponded to a high density of patches in this study) have considerable impacts on the flow structure, and to a lesser extent, individual patch elements also have a crucial role.

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Computational Analysis of Turbulent Flow Around a Dimpled and Smooth Sphere

Volume 1: Fora, Parts A, B, C, and D ◽

10.1115/fedsm2003-45432 ◽

2003 ◽

Cited By ~ 2

Author(s):

Khalid N. Alammar

Keyword(s):

Turbulent Flow ◽

Drag Coefficient ◽

Flow Structure ◽

Computational Analysis ◽

Vortex Pair ◽

Vortical Flow ◽

Separation Point ◽

Wake Region ◽

Center Point ◽

Smooth Sphere

Steady turbulent flow around a 43-mm diameter smooth sphere and one with 245 round dimples was simulated. The turbulent flow around the sphere was attained by placing a turbulator 9 mm’s upstream of the center point. For comparison, the turbulator was also placed around the dimpled sphere. The simulation revealed stable vortical flow structure inside the dimples. A stable vortex pair in the wake region was predicted in both cases. Predicted separation point over the smooth sphere was further downstream than in the case of dimpled sphere. The predicted drag coefficient for the smooth sphere was 40% lower than that of the dimpled sphere, which was 0.35. Drag predictions are compared with previously published measurements.

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Control of flow structure in the wake region of circular cylinder with meshy wire in deep water

Pamukkale University Journal of Engineering Sciences ◽

10.5505/pajes.2016.41033 ◽

2016 ◽

Vol 22 (4) ◽

pp. 280-284 ◽

Cited By ~ 1

Author(s):

Burcu Oğuz ◽

Mustafa Atakan Akar ◽

Engin Pınar ◽

Hüseyin Akıllı ◽

Beşir Şahin

Keyword(s):

Circular Cylinder ◽

Flow Structure ◽

Deep Water ◽

Wake Region ◽

Control Of Flow

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A Shelved Structure for the Support of An Electron Optical Column

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100068825 ◽

1970 ◽

Vol 28 ◽

pp. 366-367

Author(s):

P.H. McLaughlin

Keyword(s):

Electron Source ◽

Floating Platform ◽

Supporting Structure

A shelved structure for the support of an electron optical column affords advantages both to the designer and the user. A lens may be removed for cleaning for example, without demounting the remaining lenses. A custom device for another example, may be placed on a shelf, substituting for the standard lens perhaps so that some specialized research may be undertaken. Especially advantageous is a shelved arrangement if the column assembly is designed to hang from a supporting structure such as a gas borne floating platform, as is the case with the system described below.As shown on the schematic, a floating platform (I) supports the electron source apparatus (2) and a U-shaped column support shelf (3). The column support shelf acts as a key for locating and supporting three struts (4) which with nuts (5) support the condenser shelf (6), the objective shelf (7), the upper projector shelf (8), and the lower projector shelf (9).

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