Wave Diffraction by a Vertical Cylinder with a Porous Ring Plate

2002 ◽  
Vol 128 (2) ◽  
pp. 164-171 ◽  
Author(s):  
Jianhua Wu ◽  
Allen T. Chwang
Keyword(s):  
Wave Diffraction ◽  
Vertical Cylinder ◽  
Ring Plate

scholarly journals Boussinesq Model and CFD Simulations of Non-Linear Wave Diffraction by a Floating Vertical Cylinder

2020 ◽  
Vol 8 (8) ◽  
pp. 575
Author(s):  
Sarat Chandra Mohapatra ◽  
Hafizul Islam ◽  
C. Guedes Soares
Keyword(s):  
Wave Diffraction ◽  
Perturbation Technique ◽  
Harmonic Wave ◽  
Vertical Cylinder ◽  
Numerical Data ◽  
Second Order ◽  
Wave Number ◽  
Linear Wave ◽  
Cfd Simulations ◽  
Boussinesq Model

A mathematical model for the problem of wave diffraction by a floating fixed truncated vertical cylinder is formulated based on Boussinesq equations (BEs). Using Bessel functions in the velocity potentials, the mathematical problem is solved for second-order wave amplitudes by applying a perturbation technique and matching conditions. On the other hand, computational fluid dynamics (CFD) simulation results of normalized free surface elevations and wave heights are compared against experimental fluid data (EFD) and numerical data available in the literature. In order to check the fidelity and accuracy of the Boussinesq model (BM), the results of the second-order super-harmonic wave amplitude around the vertical cylinder are compared with CFD results. The comparison shows a good level of agreement between Boussinesq, CFD, EFD, and numerical data. In addition, wave forces and moments acting on the cylinder and the pressure distribution around the vertical cylinder are analyzed from CFD simulations. Based on analytical solutions, the effects of radius, wave number, water depth, and depth parameters at specific elevations on the second-order sub-harmonic wave amplitudes are analyzed.

Numerical Simulation of Nonlinear Wave Diffraction by a Vertical Cylinder

1992 ◽  
Vol 114 (1) ◽  
pp. 36-44 ◽  
Author(s):  
C. Yang ◽  
R. C. Ertekin
Keyword(s):  
Experimental Data ◽  
Circular Cylinder ◽  
Nonlinear Wave ◽  
Wave Diffraction ◽  
Three Dimensional ◽  
Vertical Cylinder ◽  
Radiation Condition ◽  
Wave Force ◽  
Second Order ◽  
Time Stepping

A three-dimensional time domain approach is used to study nonlinear wave diffraction by a fixed, vertical circular-cylinder that extends to the sea floor. In this approach, the development of the flow can be obtained by a time-stepping procedure, in which the velocity potential of the flow at any instant of time is obtained by the boundary-element method. In the numerical calculations, the exact body-boundary condition is satisfied on the instantaneous wetted surface of the cylinder, and an extended Sommerfeld condition is developed and used as the numerical radiation condition. The fourth-order Adams-Bashford method is employed in the time stepping scheme. Calculations are done to obtain the nonlinear diffraction of solitary waves and Stokes second-order waves by a vertical circular-cylinder. Numerical results are compared with the available linear and second-order wave-force predictions for some given wave height and wavelength conditions, and also with experimental data. Present horizontal force results agree better with the experimental data than the previous predictions.

Computations of fully nonlinear three-dimensional wave–wave and wave–body interactions. Part 2. Nonlinear waves and forces on a body

2001 ◽  
Vol 438 ◽  
pp. 41-66 ◽  
Author(s):  
YUMING LIU ◽  
MING XUE ◽  
DICK K. P. YUE
Keyword(s):  
Steady State ◽  
Wave Diffraction ◽  
High Harmonic ◽  
Three Dimensional ◽  
Vertical Cylinder ◽  
Fully Nonlinear ◽  
Bow Wave ◽  
Stokes Waves ◽  
State Force ◽  
Dimensional Wave

The mixed-Eulerian–Lagrangian method using high-order boundary elements, described in Xue et al. (2001) for the simulation of fully nonlinear three-dimensional wave–wave and wave–body interactions, is here extended and applied to the study of two nonlinear three-dimensional wave–body problems: (a) the development of bow waves on an advancing ship; and (b) the steep wave diffraction and nonlinear high-harmonic loads on a surface-piercing vertical cylinder. For (a), we obtain convergent steady-state bow wave profiles for a flared wedge, and the Wigley and Series 60 hulls. We compare our predictions with experimental measurements and find good agreement. It is shown that upstream influence, typically not accounted for in quasi-two-dimensional theory, plays an important role in bow wave prediction even for fine bows. For (b), the primary interest is in the higher-harmonic ‘ringing’ excitations observed and quantified in experiments. From simulations, we obtain fully nonlinear steady-state force histories on the cylinder in incident Stokes waves. Fourier analysis of such histories provides accurate predictions of harmonic loads for which excellent comparisons to experiments are obtained even at third order. This confirms that ‘ringing’ excitations are directly a result of nonlinear wave diffraction.

Second-order wave diffraction by a vertical cylinder

1992 ◽  
Vol 240 (-1) ◽  
pp. 571 ◽  
Author(s):  
F. P. Chau ◽  
R. Eatock Taylor
Keyword(s):  
Wave Diffraction ◽  
Vertical Cylinder ◽  
Second Order

scholarly journals Hydroelastic wave diffraction by a vertical cylinder

2011 ◽  
Vol 369 (1947) ◽  
pp. 2832-2851 ◽  
Author(s):  
Paul Brocklehurst ◽  
Alexander Korobkin ◽  
Emilian I. Părău
Keyword(s):  
Incident Wave ◽  
Wave Diffraction ◽  
Plate Theory ◽  
Three Dimensional ◽  
Ice Sheet ◽  
Vertical Cylinder ◽  
Finite Depth ◽  
Cylinder Surface ◽  
Linear Elastic ◽  
Potential Flow Model

A linear three-dimensional problem of hydroelastic wave diffraction by a bottom-mounted circular cylinder is analysed. The fluid is of finite depth and is covered by an ice sheet, which is clamped to the cylinder surface. The ice stretches from the cylinder to infinity in all lateral directions. The hydroelastic behaviour of the ice sheet is described by linear elastic plate theory, and the fluid flow by a potential flow model. The two-dimensional incident wave is regular and has small amplitude. An analytical solution of the coupled problem of hydroelasticity is found by using a Weber transform. We determine the ice deflection and the vertical and horizontal forces acting on the cylinder and analyse the strain in the ice sheet caused by the incident wave.

Sign in / Sign up

Export Citation Format

Share Document