Hydrodynamic interactions between cnoidal waves and a concentric cylindrical structure with arc-shaped outer cylinder

Zhai, Zhenfeng; Huang, Hua; Ye, Weifeng; Yang, Lele; Liu, Sen

doi:10.1016/j.oceaneng.2020.107448

Cited by 12 publications

(4 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Relatively little work has been done on higher-order or non-linear potential-flow models for porous structures. Interaction of cnoidal waves with an array of vertical concentric porous cylinders has been investigated by Weng et al (2016) and with a concentric cylindrical structure with an arc-shaped outer cylinder by Zhai et al (2020). Solitary waves have been used to study interaction with a concentric porous cylinder system, done by Zhong and Wang (2006), or with vertical wall porous breakwaters, done by Lynett et al (2000).…”

Section: Introductionmentioning

confidence: 99%

Using a porous-media approach for CFD modelling of wave interaction with thin perforated structures

Feichtner

Mackay

Tabor

et al. 2020

J. Ocean Eng. Mar. Energy

View full text Add to dashboard Cite

This work presents the use of a porous-media approach for computational fluid dynamics (CFD) modelling of wave interaction with thin perforated sheets and cylinders. The perforated structures are not resolved explicitly but represented by a volumetric porous zone where a volume-averaged pressure gradient in the form of a drag term is applied to the Navier–Stokes momentum equation. The horizontal force on the structures and the free-surface elevation at wave gauges around the cylinder model have been analysed for a range of porosities and regular wave conditions. The CFD results are verified against results from a linear potential-flow model and validated against experimental results. The applied pressure gradient formulation produces good agreement for all porosity values, wave frequencies and wave steepnesses investigated. It is demonstrated that an isotropic macroscopic porosity representation used for large volumetric granular material can also be used for thin perforated structures. This approach offers greater flexibility in the range of wave conditions that can be modelled compared to approaches based on linear potential-flow theory and requires a smaller computational effort compared to CFD approaches which resolve the flow through the openings. The approach can therefore be an efficient alternative for engineering problems where large-scale effects such as global forces and the overall flow-behaviour are of the main interest.

show abstract

Section: Introductionmentioning

confidence: 99%

Using a porous-media approach for CFD modelling of wave interaction with thin perforated structures

Feichtner

Mackay

Tabor

et al. 2020

J. Ocean Eng. Mar. Energy

View full text Add to dashboard Cite

show abstract

“…Later, Behera et al (2020) studied the influence of a truncated concentric porous cylinder on the inner rigid platform, where the optimum number of porous structures for damping the wave amplitude was estimated. Recently, the cnoidal wave diffraction from the dual concentric cylinders in the presence of an arc-shaped outer cylinder was analyzed by Zhai et al (2020).…”

Section: Introductionmentioning

confidence: 99%

Surface wave scattering by multiple flexible fishing cage system

et al. 2021

View full text Add to dashboard Cite

A study of the wave dynamics around a multiple cylindrical fishing cage system is carried out under the assumption of linear water wave theory and small-amplitude wave response. The Fourier-Bessel series expansion of the velocity potential is derived for the regions enclosed under the open-water and cage systems and the immediate vicinity. The scattering between the cages is accounted for by employing Graf's addition theorem. The porous flexible cage system is modeled using Darcy's law and the three-dimensional membrane equation. The edges of the cages are moored along their circumferences to balance its position. The unknown coefficients in the potentials are obtained by employing the matched eigenfunction method. In addition, the far-field scattering coefficients for the entire system are obtained by expanding the Bessel and Hankel functions in the plane wave representation form. Numerical results for the hydrodynamic forces, scattering coefficients, and power dissipation are investigated for various cage and wave parameters. The time simulation for the wave scattering from the cage system is investigated. The study reveals that wave loading on the cage system can be significantly reduced by the appropriate spatial arrangement, membrane tension, and porous-effect parameter. Moreover, the far-field results suggest that the cage system can also be used as a breakwater.

show abstract

“…The typical concentric cylindrical structure was later investigated under different types of incident waves. The interactions between such structures and different types of waves, such as solitary waves [8,9], short-crested waves [10], and cnoidal waves [11,12], have been studied by several researchers. Additionally, many studies have focused on the modification of concentric cylindrical structures to develop a concentric dual-arc structure [13], truncated cylinder with an upper porous cylinder [14], or floating compound porous cylinder [15].…”

Section: Introductionmentioning

confidence: 99%

Analytical Solution for Wave Diffraction by a Concentric Three-Cylinder System near a Vertical Wall

Zhai

Xia

et al. 2021

Mathematics

Self Cite

View full text Add to dashboard Cite

In this study, a semi-analytical model was developed to study wave diffraction around a concentric three-cylinder system near a wall based on linear potential theory. As a critical element, the target problem is transformed into bidirectional incident wave diffraction around two concentric structures based on the image principle and an analytical solution is obtained through eigenfunction expansion combined with a matching technique and Graf’s addition theorem. The validity of the proposed model was verified by comparing its results to known values. Parametric studies on porosity, annular spacing, incident angle, space between the structure and wall, and water depth were performed. The hydrodynamic loads and free-surface elevations in the system were calculated and compared to those reported in existing works on impermeable and permeable cylinders near a wall. The results indicate that the wave loads and run-ups on the exterior cylinder increase significantly based on the existence of the wall. However, based on the presence of an exterior porous protective structure, a significantly reduced influence of the wall on the interior cylinder can be observed. Considering the widespread use of concentric circular structures in ocean engineering, it is essential to conduct study on the hydrodynamic performance of concentric systems near walls, which can provide useful information for the design of marine structures.

show abstract

Hydrodynamic interactions between cnoidal waves and a concentric cylindrical structure with arc-shaped outer cylinder

Cited by 12 publications

References 36 publications

Using a porous-media approach for CFD modelling of wave interaction with thin perforated structures

Using a porous-media approach for CFD modelling of wave interaction with thin perforated structures

Surface wave scattering by multiple flexible fishing cage system

Analytical Solution for Wave Diffraction by a Concentric Three-Cylinder System near a Vertical Wall

Contact Info

Product

Resources

About