Near-wake characteristics of various V-shaped bluff bodies

1994 ◽  
Vol 10 (1) ◽  
pp. 47-53 ◽  
Author(s):  
Jing-Tang Yang ◽  
Go-Long Tsai ◽  
Wen-Bin Wang
Keyword(s):  
Bluff Bodies ◽  
Near Wake ◽  
Wake Characteristics

Numerical Investigation of Flow Around Bluff Bodies

1998 ◽  
Vol 14 (3) ◽  
pp. 153-159 ◽  
Author(s):  
Chou-Jiu Tsai ◽  
Ger-Jyh Chen
Keyword(s):  
Vortex Shedding ◽  
Stokes Equations ◽  
Navier Stokes ◽  
Bluff Bodies ◽  
Near Wake ◽  
Navier Stokes Equations ◽  
Physical Description ◽  
Geometrical Shapes ◽  
Flow Phenomena ◽  
Volume Method

ABSTRACTIn this study, fluid flow around bluff bodies are studied to examine the vortex shedding phenomenon in conjuction with the geometrical shapes of these vortex shedders. These flow phenomena are numerically simulated. A finite volume method is employed to solve the incompressible two-dimensional Navier-Stokes equations. Thus, quantitative descriptions of the vortex shedding phenomenon in the near wake were made, which lead to a detailed description of the vortex shedding mechanism. Streamline contours, figures of lift coefficent, and figures of drag coefficent in various time, are presented, respectively, for a physical description.

Similarity in the turbulent near wake of bluff bodies

AIAA Journal ◽  
1975 ◽  
Vol 13 (11) ◽  
pp. 1425-1429 ◽  
Author(s):  
R. K. Sullerey ◽  
A. K. Gupta ◽  
C. S. Moorthy
Keyword(s):  
Bluff Bodies ◽  
Near Wake

scholarly journals Near-wake characteristics of rigid and membrane wings in ground effect

2018 ◽  
Vol 80 ◽  
pp. 199-216 ◽  
Author(s):  
R. Bleischwitz ◽  
R. de Kat ◽  
B. Ganapathisubramani
Keyword(s):  
Ground Effect ◽  
Near Wake ◽  
Wake Characteristics

Numerical investigation of near-wake characteristics of cavitating flow over a circular cylinder

2016 ◽  
Vol 790 ◽  
pp. 453-491 ◽  
Author(s):  
Aswin Gnanaskandan ◽  
Krishnan Mahesh
Keyword(s):  
Circular Cylinder ◽  
Single Phase ◽  
Three Dimensional ◽  
Low Frequency ◽  
Reynolds Numbers ◽  
Cavitating Flow ◽  
Cylinder Surface ◽  
Near Wake ◽  
Eddy Simulation ◽  
Wake Characteristics

A homogeneous mixture model is used to study cavitation over a circular cylinder at two different Reynolds numbers ($Re=200$ and 3900) and four different cavitation numbers (${\it\sigma}=2.0$, 1.0, 0.7 and 0.5). It is observed that the simulated cases fall into two different cavitation regimes: cyclic and transitional. Cavitation is seen to significantly influence the evolution of pressure, boundary layer and loads on the cylinder surface. The cavitated shear layer rolls up into vortices, which are then shed from the cylinder, similar to a single-phase flow. However, the Strouhal number corresponding to vortex shedding decreases as the flow cavitates, and vorticity dilatation is found to play an important role in this reduction. At lower cavitation numbers, the entire vapour cavity detaches from the cylinder, leaving the wake cavitation-free for a small period of time. This low-frequency cavity detachment is found to occur due to a propagating condensation front and is discussed in detail. The effect of initial void fraction is assessed. The speed of sound in the free stream is altered as a result and the associated changes in the wake characteristics are discussed in detail. Finally, a large-eddy simulation of cavitating flow at $Re=3900$ and ${\it\sigma}=1.0$ is studied and a higher mean cavity length is obtained when compared to the cavitating flow at $Re=200$ and ${\it\sigma}=1.0$. The wake characteristics are compared to the single-phase results at the same Reynolds number and it is observed that cavitation suppresses turbulence in the near wake and delays three-dimensional breakdown of the vortices.

The effect of flow perturbations on the near wake characteristics of a circular cylinder

2003 ◽  
Vol 18 (3-4) ◽  
pp. 367-386 ◽  
Author(s):  
E. Konstantinidis ◽  
S. Balabani ◽  
M. Yianneskis
Keyword(s):  
Circular Cylinder ◽  
Near Wake ◽  
Wake Characteristics

Flow Over Two Circular Disks in Tandem

1980 ◽  
Vol 102 (1) ◽  
pp. 104-111 ◽  
Author(s):  
T. Morel ◽  
M. Bohn
Keyword(s):  
Drag Reduction ◽  
Steady Flow ◽  
Unsteady Flows ◽  
Flow Regimes ◽  
Diameter Ratio ◽  
Bluff Bodies ◽  
Steady Flows ◽  
Near Wake ◽  
Total Drag ◽  
Circular Disks

Placing two or more bluff-bodies in tandem is known to lead, in some cases, to configurations with relatively low overall drag. The present study concerns one particular case where two disks of unequal diameters, normal to the flow, are placed in tandem for the purpose of drag reduction. It shows that very significant drag reductions may be achieved by proper sizing of the disk diameters and of the gap between them. Placing a properly sized disk at an optimum distance ahead of a single reference disk can result in a configuration whose total drag is up to 81 percent lower than that of the reference disk alone. If the additional disk is placed behind into the near-wake of the reference disk, the drag of the two-disk configuration can be up to 70 percent lower than for the reference disk alone. Four different flow regimes have been identified, depending on the diameter ratio of the two disks, two with relatively steady flows and two with unsteady flows. The absolute drag minimum was found to occur in one of the two steady-flow regimes.

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