Numerical Study on Hydrodynamic Force and Wave Induced Vortex Dynamics around Cylindrical Pile

The wave-induced resonant flow in a narrow gap between a stationary hull and a vertical wall is studied experimentally and numerically. Vortex shedding from the sharp bilge edge of the hull gives rise to a quadratically damped free surface response in the gap, where the damping coefficient is approximately independent of wave steepness and frequency. Particle image velocimetry and direct numerical simulations were used to characterise the shedding dynamics and explore the influence of discretisation in the measurements and computations. Secondary separation was identified as a particular feature which occurred at the hull bilge in these gap flows. This can result in the generation of a system with multiple vortical regions and asymmetries between the inflow and outflow. The shedding dynamics was found to exhibit a high degree of invariance to the amplitude in the gap and the spanwise position of the barge. The new measurements and the evaluation of numerical models of varying fidelity can assist in informing offshore operations such as the side by side offloading from floating liquefied natural gas facilities.

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Numerical study of air-core vortex dynamics during liquid draining from cylindrical tanks

Fluid Dynamics Research ◽

10.1088/0169-5983/46/2/025508 ◽

2014 ◽

Vol 46 (2) ◽

pp. 025508 ◽

Cited By ~ 7

Author(s):

Sam Mathew ◽

B S V Patnaik ◽

T John Tharakan

Keyword(s):

Vortex Dynamics ◽

Numerical Study ◽

Air Core ◽

Cylindrical Tanks

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Numerical study for wave-induced oscillatory pore pressures and liquefaction around impermeable slope breakwater heads

Ocean Engineering ◽

10.1016/j.oceaneng.2018.03.058 ◽

2018 ◽

Vol 157 ◽

pp. 364-375 ◽

Cited By ~ 24

Author(s):

Chencong Liao ◽

Dagui Tong ◽

Dong-Sheng Jeng ◽

Hongyi Zhao

Keyword(s):

Numerical Study ◽

Pore Pressures ◽

Wave Induced

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Numerical study on wave-induced hydro-elastic responses of a floating raft for aquaculture

Ocean Engineering ◽

10.1016/j.oceaneng.2021.109869 ◽

2021 ◽

Vol 240 ◽

pp. 109869

Author(s):

Bei Chu ◽

Yiren Chen ◽

Yao Zhang ◽

Guangming Zhang ◽

Xu Xiang ◽

...

Keyword(s):

Numerical Study ◽

Floating Raft ◽

Elastic Responses ◽

Wave Induced

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A Numerical Study of Heat Transfer Enhancement by a Rectangular Cylinder Placed Parallel to the Heated Wall

Journal of Heat Transfer ◽

10.1115/1.4043212 ◽

2019 ◽

Vol 141 (7) ◽

Cited By ~ 3

Author(s):

J. F. Derakhshandeh ◽

Md. Mahbub Alam

Keyword(s):

Heat Transfer ◽

Vortex Dynamics ◽

Numerical Study ◽

Vortex Street ◽

Heated Wall ◽

Transfer Enhancement ◽

Maximum Heat ◽

Single Row ◽

Rectangular Cylinder ◽

Maximum Heat Transfer

The flow around a rectangular cylinder mounted in the vicinity of a hot wall is numerically studied at a Reynolds number of 200. While the cylinder chord-to-height ratio C/W is varied from 2 to 10, the gap distance G from the wall to the cylinder is changed from 0.25 to 6.25. The focus of this study is given on the dependence of G/W and C/W on the heat transfer from the wall and associated physics. The variation in the Strouhal number is presented as a function of C/W. It is observed that the effect of G/W on the vortex dynamics and heat transfer is much more than that of C/W. Based on the dependence of the vortex dynamics and heat transfer on G/W, we have identified four distinct flows: no vortex street flow (G/W < 0.75), single-row vortex street flow (0.75 ≤ G/W ≤ 1.25), inverted two-row vortex street flow (1.25 < G/W ≤ 2.5), and two-row vortex street flow (G/W > 2.5). At the single-row vortex street flow, the two opposite-sign vortices appearing in a jetlike flow carry heat from the wall to the wake and then to the freestream. The maximum heat transfer is achieved at the single-row vortex street flow and 8% increase occurs at C/W = 2, G/W = 0.75–1.25.

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Numerical study of trailing and leading vortex dynamics in a forced jet with coflow

Computers & Fluids ◽

10.1016/j.compfluid.2019.02.001 ◽

2019 ◽

Vol 181 ◽

pp. 314-344

Author(s):

Bharat Bhatia ◽

Ashoke De

Keyword(s):

Vortex Dynamics ◽

Numerical Study

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3-Dimensional numerical study of wave-induced seabed response around three different types of wind turbine pile foundations

SN Applied Sciences ◽

10.1007/s42452-019-1484-2 ◽

2019 ◽

Vol 1 (11) ◽

Cited By ~ 1

Author(s):

Richard Asumadu ◽

Jisheng Zhang ◽

H. Y. Zhao ◽

Hubert Osei-Wusuansa ◽

Alex Baffour Akoto

Keyword(s):

Wind Turbine ◽

Numerical Study ◽

Pile Foundations ◽

3 Dimensional ◽

Different Types ◽

Wave Induced

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Numerical Study on Seakeeping Performance of a Damaged Ship

Volume 9: Rodney Eatock Taylor Honoring Symposium on Marine and Offshore Hydrodynamics; Takeshi Kinoshita Honoring Symposium on Offshore Technology ◽

10.1115/omae2019-96193 ◽

2019 ◽

Author(s):

Lu-Ning Cui ◽

Yi Zheng ◽

Yinggang Li ◽

Ling Zhu ◽

Mingsheng Chen

Keyword(s):

Numerical Study ◽

Rolling Motion ◽

Wave Direction ◽

Regular Waves ◽

Motion Responses ◽

Seakeeping Performance ◽

Property Losses ◽

Hull Damage ◽

Wave Induced ◽

Damaged Ship

Abstract Ships sailing in the sea may encounter collision, grounding or projectile impacting accidents, which may cause hull damage and subsequent compartment flooding. Due to the effect of the flooding water induced moment and the restoring moment, the damaged ship may have inclination and rolling motion. When the inclination or the rolling motion is too large, it may affect the safety and survivability of ship in navigation and cause severe casualties and property losses. In order to increase the navigation safety and survivability of the damaged ship, a numerical model is established based on the potential flow theory to investigate the seakeeping performance of the damaged ship in two scenarios, i.e., the case before ship damaged, and the case when the damaged ship reaching a relatively stable floating state. The heave, pitch and roll motion responses and corresponding wave-induced loads acting on the ship are analyzed in regular waves. In addition, the effects of the navigation speed and the wave direction on the seakeeping performance are also investigated.

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