Numerical Investigation on Vortex-Induced Vibration Suppression of a Circular Cylinder with Axial-Slats

Abstract

The vortex-induced vibration (VIV) suppression of a circular cylinder with the axial-slats is numerically investigated using the computational fluid dynamics (CFD) method for Reynolds number range of 8.0 × 10 3 -5.6 × 10 4 . The two-dimensional unsteady Reynolds averaged Navier-Stokes (RANS) equations and Shear-Stress-Transport (SST) turbulence model are used to calculate the flow around the cylinder in ANSYS Fluent. The Newmark-β method is used to evaluate structural dynamics. The amplitude response, frequency response and vortex pattern are discussed. The suppression effect of the axial-slats is the best when the gap ratio is 0.10 and the coverage ratio is 30%. Based on the VIV response, the whole VIV response region is divided into four regions (Region I, Region II, Region III and Region IV). The frequency ratio of isolated cylinder jumps between region II and region III. However, the frequency ratio jumps between region I and region II for a cylinder with the axial-slats. The axial-slats destroy the original vortex and make the vortex easier to separate. The online amplitude ratio is almost completely suppressed, and the cross-flow amplitude ratio is significantly suppressed. effect of different surface roughness on VIV suppression, and results showed that the amplitude response decreased and drag coefficient decreased as the roughness increases. Zhu and Yao [13] presented a method of VIV suppression using small control rods, and results showed that the suppression effect was the best when the number of control rods was 9. The suppression effect of traveling wave wall (TWW) on VIV was studied numerically by Xu et al. [14], and a small vortex shedding was observed. A circular cylinder attached with helical strakes on VIV suppression was numerically investigated [15], and it could be found that helical strake could change vibration frequency and suppress the vortex shedding. Huera-Huarte [16] investigated the suppression effect of wire meshes on VIV, and the maximum amplitude response could be reduced by 95%. Lou et al. [17] experimentally investigated the suppression effect of splitter plates, and it was found that the length ratio of splitter plate was an important factor on VIV suppression. Zheng and Wang [18] investigated the suppression effect of different shaped fairing devices on VIV. There are many researches on axial-rods [19][20][21], but there are few researches on axial-slats.In this study, the VIV response of a circular cylinder with the axial-slats is numerically investigated using the computational fluid dynamics (CFD) method for Reynolds number range of 8.0 × 10 3 < Re < 5.6 × 10 4 . The two-dimensional unsteady Reynolds averaged Navier-Stokes (RANS) equations in conjunction with the SST k-ω turbulence model are used to calculate the flow around the cylinder. The Newmark-β method is used to evaluate the structural dynamics. The physical model is established in Section 2, and the numerical model is established in Section 3. In Section 3, the numerical model is verified by experimental results. T...

On the Spanwise Periodicity within the Gap between Two Different-Sized Tandem Circular Cylinders at Re = 3900

“…Despite the simplicity of the geometry, the flow around cylindrical structures is of fundamental significance and involves complex flow mechanisms, including vortex shedding/impingement/interaction, shear layer separation/reattachment, transition from a steady to unsteady state, transition from a two-dimensional (2D) to three-dimensional (3D) state, fluid-structure interaction, and flow-induced noise/vibration [1][2][3][4][5]. Abundant studies have been conducted to elucidate the flow around circular or square cylinders, due to their extensive engineering applications [6][7][8][9][10].…”

On the Spanwise Periodicity within the Gap between Two Different-Sized Tandem Circular Cylinders at Re=3900

“…Despite the simplicity of the geometry, the flow around cylindrical structures is of fundamental significance and involves complex flow mechanisms, including vortex shedding/impingement/interaction, shear layer separation/reattachment, transition from steady to unsteady state, transition from two-dimensional (2D) to three-dimensional (3D) state, fluid-structure interaction and flow-induced noise/vibration [1][2][3][4][5]. Abundant studies have been conducted to elucidate the flow around circular or square cylinders, due to their extensive engineering applications [6][7][8][9][10].…”

On the Spanwise Periodicity within the Gap between Two Different-Sized Tandem Circular Cylinders at Re=3900

“…Despite the simplicity of the geometry, the flow around cylindrical structures is of fundamental significance and involves complex flow mechanisms, including vortex shedding/ impingement/ interaction, shear layer separation/reattachment, transition from steady to unsteady state, transition from two-dimensional (2D) to three-dimensional (3D) state, fluid-structure interaction and flowinduced noise/vibration [1][2][3][4][5]. Abundant studies have been conducted to elucidate the flow around circular or square cylinders, due to their extensive engineering applications [6][7][8][9][10].…”