Investigation of turbulent flow past a flagged short finite circular cylinder

Kiani, Farzad; Javadi, Khodayar

doi:10.1080/14685248.2015.1125491

Cited by 8 publications

(5 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The same phenomenon was presented by Kiani and Javadi on a flagged short-finite circular cylinder. 43 This flow behavior can also be found in the region of super flow at critical values of Re from 5 × 10 5 to 3.5 × 10 6 for a smooth circular cylinder. 44 As the velocity increased, the dominant frequency of vortex shedding was as shown in Figure 12(b) and (d).…”

Section: Numerical Results and Discussionmentioning

confidence: 55%

Experimental and numerical investigation of flow over spiral grooved cylinders

Jun

Cheng

Liu

et al. 2022

Advances in Mechanical Engineering

View full text Add to dashboard Cite

This study experimentally and numerically investigates the performance of a circular cylinder with a spiral grooved surface in terms of reducing wind drag. Its application in the overhead high-power conductor plays a vital role, especially in typhoon conditions. Wind tunnel tests have shown that at the critical Reynolds number (Re), the coefficients of wind drag decrease to a greater extent in a spiral grooved cylinder than in a smooth circular one. Moreover, a cylinder with a shallow groove and a small number of spirals could reduce the coefficient of drag in typhoon conditions. To gain an insight into the underlying fluid mechanism, a large-eddy simulation of turbulent flow from a critical to a super-critical Re has been carried out to approximate the flow separation and turbulent eddies over the spiral grooved cylinder. The results of the wind tunnel test have been used as a benchmark for the numerical results. The flow characteristics have been established about the near-wall flow separation and far wake flow, the pressure coefficient, the skin-friction coefficient, drag coefficient, and Q-criterion field.

show abstract

Section: Numerical Results and Discussionmentioning

confidence: 55%

Experimental and numerical investigation of flow over spiral grooved cylinders

Jun

Cheng

Liu

et al. 2022

Advances in Mechanical Engineering

View full text Add to dashboard Cite

show abstract

“…1,12 Additionally, despite the geometrical differences between cylinders and conical structures, the results presented here demonstrate that the wake and hydrodynamic forces are characterised by a single energy peak which is in line with studies conducted with cylinders. 10 …”

Section: F Hydrodynamic Forces and Far-wake Characterisationmentioning

confidence: 99%

“…Streamwise tip vortices formed off the freeend of the obstacle have been observed for a variety of object shapes and profiles. 5,[8][9][10][11] These vortices shift downwards with the downwash flow, 5 and for the case of cylinders with smaller aspect ratios, they occupy a greater proportion of the water column and therefore dominate the turbulence structures, which prevents the development of von Karman vortex shedding. 1 Hence, in the case of flow around cylinders, vortex shedding appears to be a function of the object's aspect ratio.…”

Section: Introductionmentioning

confidence: 99%

“…LES has been widely used to study submerged cylinders 1,25 due to its ability to resolve complex phenomena such as energetic large-scale structures, flow separation at the top of the upstream face, 6,19 or tip vortices. 10 With the exception of the aforementioned studies, there is a scarcity of experimental and numerical studies examining the wakes of submerged obstacles in shallow flows despite their importance in hydraulic and geophysical contexts. 26 Furthermore, the majority of studies have focused on cylinders, cubes, or hemispheres with few studies examining other cross-sectional shape geometries pertinent to river or oceanic flows.…”

Section: Introductionmentioning

confidence: 99%

“…In deeply submerged flows, Large-Eddy Simulations (LESs) demonstrated that the tip vortices and recirculation bubbles at a cylinder's free-end are not significantly affected by the presence of a vertical plate attached to the downstream side of the cylinder and only the arch vortex and horseshoe vortex were affected. 10 For a cuboid whose upstream and leeward profiles were modified by adding a wedge and elliptical profiles, respectively, LES and experimental data have shown that the upstream face significantly impacts the attachment of overlying flow over the free-end and the flow structure of the magnitude of the downwash flow. 20 Furthermore, it was found that the interaction between the tip and lateral vortices was the greatest for the square cylinder without an upstream wedge profile or a leeside elliptical profile, resulting in a strong detachment of flow over the top of the body.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Large-eddy simulation of shallow turbulent wakes behind a conical island

et al. 2017

View full text Add to dashboard Cite

Large-Eddy Simulations (LESs) and experiments were employed to study the influence of water depth on the hydrodynamics in the wake of a conical island for emergent, shallow, and deeply submerged conditions. The Reynolds numbers based on the island’s base diameter for these conditions range from 6500 to 8125. LES results from the two shallower conditions were validated against experimental measurements from an open channel flume and captured the characteristic flow structures around the cone, including the attached recirculation region, vortex shedding, and separated shear layers. The wake was impacted by the transition from emergent to shallow submerged flow conditions with more subtle changes in time-averaged velocity and instantaneous flow structures when the submergence increases further. Despite differences in the breakdown of the separated shear layers, vortex shedding, and the upward flow region on the leeward face (once the cone’s apex is submerged), similar flow structures to cylinder flow were observed. These include an arch vortex tilted in the downstream direction and von Karman vortices in the far-wake. Spectra of velocity time series and the drag coefficient indicated that the vortex shedding was constrained by the overtopping flow layer, and thus the shedding frequency decreased as the cone’s apex became submerged. Finally, the generalised flow structures in the wake of a submerged conical body are outlined.

show abstract

Numerical investigation of flow structures and aerodynamic interference around stationary parallel box girders

Kang

Yan

et al. 2021

Journal of Wind Engineering and Industrial Aerodynamics

View full text Add to dashboard Cite

Investigation of turbulent flow past a flagged short finite circular cylinder

Cited by 8 publications

References 21 publications

Experimental and numerical investigation of flow over spiral grooved cylinders

Experimental and numerical investigation of flow over spiral grooved cylinders

Large-eddy simulation of shallow turbulent wakes behind a conical island

Numerical investigation of flow structures and aerodynamic interference around stationary parallel box girders

Contact Info

Product

Resources

About