Prediction of Turbulent Flow Around a Square Cylinder With Rounded Corners

Dai, Shaoshi; Younis, Bassam A.; Zhang, Hongyang

doi:10.1115/1.4035957

Cited by 8 publications

(5 citation statements)

References 22 publications

(42 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The computational fluid domain is shown in Figure 2a, where its dimensions are given in multiples of D. The inlet, outlet, and side boundaries of the computational domain are located at distances of 10D, 25D, and 10D, respectively, from the cross-section. The dimensions of the fluid domain were chosen so that flow development far from the cross-section was not affected and so that it could be comparable with previous numerical studies [32,33,36]. Initial analyses for varying D values confirmed that the results are independent of D; thus, this problem may be non-dimensionalized.…”

Section: Computational Modelmentioning

confidence: 99%

“…Zhang et al (2017) [35] performed URANS simulations with Spalart-Allmaras (SA), standard k-ω, and k-ω (SST) turbulence models at Re = 2.2 × 10 4 , but observed that the one-equation Wray-Agarwal (WA) turbulence model agreed more with experimental data. Finally, Dai et al (2017) [36] performed URANS simulations with the modified k-ε turbulence model, and they demonstrated the drag reduction effect of the presence of rounded corners instead of sharp ones in a square cylinder.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Unsteady Numerical Simulation of Two-Dimensional Airflow over a Square Cross-Section at High Reynolds Numbers as a Reduced Model of Wind Actions on Buildings

Karvelis,

Dimas,

Gantes

2024

Buildings

View full text Add to dashboard Cite

Airflow over a square cross-section at high Reynolds numbers and different angles of incidence is investigated with the aim of providing deeper insight into wind actions on elongated structures and, in particular, tall buildings. The flow around bluff bodies is characterized by separation at sharp corners, as well as possible flow reattachment at side surfaces. The alternate shedding of vortices is also generated in the wake of bluff bodies due to the unsteady nature of flow separation. Two-dimensional (2D) URANS numerical simulations were conducted in order to model transient flow and examine wind actions on a square used as a model of a typical cross-section of a tall building far from its roof and the ground. For validation purposes, the study’s numerical results on drag and lift coefficients, Strouhal numbers, as well as pressure coefficient distribution were found to be in good agreement with available experimental and numerical results in the literature for relatively low Reynolds numbers. The numerical study was then extended to higher Reynolds numbers, approaching values that are pertinent for wind flow around buildings, thus addressing the lack of such results in the literature. On the basis of these results, the impact of Reynolds numbers and angles of incidence on drag and lift coefficients, as well as the pressure coefficient distribution along the walls of the cross-section, is highlighted.

show abstract

Section: Computational Modelmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Unsteady Numerical Simulation of Two-Dimensional Airflow over a Square Cross-Section at High Reynolds Numbers as a Reduced Model of Wind Actions on Buildings

Karvelis,

Dimas,

Gantes

2024

Buildings

View full text Add to dashboard Cite

show abstract

“…The proposed modification was subsequently tested in a wide range of flows that are strongly influenced by vortex shedding. These included the benchmark flow around isolated square and circular cylinders (Younis and Przulj, 2006), the flow around a full-scale Tension Leg Platform (Dai et al, 2015), and the flow around a square cylinder with rounded corners (Dai et al, 2017). In each case the results obtained with the modified model were distinctly better than those obtained with the standard formulation.…”

Section: Computational Detailsmentioning

confidence: 99%

Prediction of vortex shedding suppression from circular cylinders at high Reynolds number using base splitter plates

Dai

Younis

Zhang

et al. 2018

Journal of Wind Engineering and Industrial Aerodynamics

View full text Add to dashboard Cite

Computations were performed to determine the optimal conditions for the suppression of vortex shedding from circular cylinders at high Reynolds number by means of splitter plates. Previous studies of this mechanism for vortex-shedding control have largely been confined to two-dimensional flows at low Reynolds number, and to a single ratio of splitter plate width to cylinder diameter. In this study, we consider fully-turbulent, three-dimensional flows at high Reynolds number, and investigate the dependence of vortex-shedding suppression on two geometric parameters; namely the ratio of splitter-plate width and height to cylinder diameter and length. The computations were performed with the OpenFOAM software using a well-validated turbulence closure that considers the effects of the organized mean-flow unsteadiness on the random turbulent fluctuations. Comparisons were made with experimental data, and the validated method is used to perform a systematic study to determine the effectiveness of vortex suppression. To aid in the analysis, two-point correlations of forces along span of cylinder were obtained to determine uncoupling conditions of sectional oscillations. The results obtained indicate that splitter plates provide a practical method for vortex suppression at high Reynolds number, and the degree of suppression can be maximized by optimal geometric configuration.

show abstract

“…They further extended their work by studying the shear-inflow effects for the above simulated cases in [23] and [24]. Other numerical studies on rounded corner cylinders are summarised in [25,26].…”

Section: Introductionmentioning

confidence: 97%

A 3D Numerical Investigation into the Effect of Rounded Corner Radii on the Wind Loading of a Square Cylinder Subjected to Supercritical Flow

Vishwanath,

Saravanakumar,

Dwivedi

et al. 2021

Preprint

View full text Add to dashboard Cite

Tall buildings are often subjected to steady and unsteady forces due to external wind flows. Measurement and mitigation of these forces becomes critical to structural design in engineering applications. Over the last few decades, many approaches such as modification of the external geometry of structures have been investigated to mitigate wind-induced load. One such proven geometric modifications involved rounding of sharp corners. In this work, we systematically analyze the effects of rounded corner radii on the flow-induced loading for a square cylinder. We perform 3-Dimensional (3D) simulations at a high Reynolds number of Re = 1 × 10 5 which is more likely to be encountered in practical applications. An Improved Delayed Detached Eddy Simulation (IDDES) formulation is used with the k − ω Shear Stress Transport (SST) model for near-wall modelling. IDDES is capable of capturing flow accurately at high Reynolds numbers and prevents grid-induced separation near the boundary layer. The effects of these corner modifications are analyzed in terms of the resulting mean and fluctuating components of the lift and drag forces compared to a sharp corner case. Plots of the angular distribution of the mean and fluctuating pressure coefficient along the square cylinder's surface illustrate the effects of corner modifications on the different parts of the cylinder. The windward corner's separation angle was observed to decrease with an increase in radius, resulting in a narrower and longer recirculation region. Furthermore, with an increase in radius, a reduction in the fluctuating lift, mean drag, and fluctuating

show abstract

Prediction of Turbulent Flow Around a Square Cylinder With Rounded Corners

Cited by 8 publications

References 22 publications

Unsteady Numerical Simulation of Two-Dimensional Airflow over a Square Cross-Section at High Reynolds Numbers as a Reduced Model of Wind Actions on Buildings

Unsteady Numerical Simulation of Two-Dimensional Airflow over a Square Cross-Section at High Reynolds Numbers as a Reduced Model of Wind Actions on Buildings

Prediction of vortex shedding suppression from circular cylinders at high Reynolds number using base splitter plates

A 3D Numerical Investigation into the Effect of Rounded Corner Radii on the Wind Loading of a Square Cylinder Subjected to Supercritical Flow

Contact Info

Product

Resources

About