Application of Direct Boundary Element Method to Three Dimensional Hydrodynamic Analysis of Interaction Between Waves and Floating Offshore Structures

A three-dimensional hydrodynamic analysis of interaction between a floating offshore structure and sea waves has been carried out using a novel approach which is based on the weighted residual technique and the direct boundary element method. The main advantage of the direct boundary element method is the fact that one can determine the total velocity potential directly. Direct BEM is more versatile and computationally more efficient than indirect BEM. Besides, the BEM can easily be coupled with other numerical methods, e.g. finite element method (FEM) in order to carry out structural analysis of deck of the platform due to impact. Firstly, the boundary value problem of three-dimensional interaction between regular sea waves and a semi-submersible will be described. Secondly, the direct boundary element method has been applied to predict hydrodynamic behaviour of Khazar Semi-Submersible Drilling Unit (KSSDU), which is the largest semi-submersible drilling platform under construction for a location in the Caspian Sea, North of Iran. The rigid body motion responses in six degrees of freedom of KHAZAR semi-submersible in response to encountering waves have been calculated by using the direct boundary element method. The results obtained from the direct BEM will be compared with those obtained by the results based on the conventional boundary element method (indirect BEM) which were obtained by the designers of KHAZAR semi-submersible.

24th International Conference on Offshore Mechanics and Arctic Engineering: Volume 1, Parts A and B ◽

Numerical Prediction of Air Gap Response of Floating Offshore Structures Using Direct Boundary Element Method

10.1115/omae2005-67399 ◽

2005 ◽

Cited By ~ 2

Author(s):

Saeid Kazemi ◽

Atilla Incecik

Keyword(s):

Boundary Element Method ◽

Boundary Element ◽

Offshore Structures ◽

Air Gap ◽

Analytical Prediction ◽

Sea Waves ◽

Floating Structure ◽

The Caspian Sea ◽

The air gap response and potential deck impact of ocean structures under waves is the main topic of this research. In this paper, an analytical prediction of the air gap for floating offshore structures using direct Boundary Element Method (BEM) is presented. The main advantage of direct boundary element method is the fact that one can determine the total velocity potential directly. Direct BEM is more versatile and computationally more efficient than indirect BEM. Besides, the direct BEM can easily be coupled with other numerical methods, e.g. finite element method (FEM) in order to carry out structural analysis of the platform’s deck due to possible impact. Firstly, the direct boundary element method will be reviewed. Secondly, the boundary value problem of interaction between regular sea waves and a semi-submersible and air gap responses due to the motion of the platform and the local wave elevations (including both radiation and diffraction waves) will be described. Then, the direct boundary element method will be applied to predict of the air gap at different field points of ALBORZ semi-submersible drilling unit, which is the largest semi-submersible drilling platform under construction for a location in the Caspian Sea, North of Iran. In addition, the results obtained from the direct BEM will be compared with those obtained by the designers of the ALBORZ semi-submersible. To determine the influence of the structure’s motions on the air gap, the results for both fixed and free-floating structure cases will be compared. Physical simulations using model will be carried out in the future in order to compare the results of the experiments with predictions.

Some improvements of accuracy and efficiency in three dimensional direct boundary element method

International Journal for Numerical Methods in Engineering ◽

10.1002/nme.1620330706 ◽

1992 ◽

Vol 33 (7) ◽

pp. 1451-1464 ◽

Cited By ~ 12

Author(s):

Yin-Sheng Li ◽

Tatsuo Obata ◽

Hideo Koguchi ◽

Toshio Yada

Keyword(s):

Boundary Element Method ◽

Boundary Element ◽

Three Dimensional ◽

Hydrodynamic Analysis of 3D Hydrofoil Using Nonuniform Rational B-Spline and Boundary Element Method

Mathematical Problems in Engineering ◽

10.1155/2021/7252949 ◽

2021 ◽

Vol 2021 ◽

pp. 1-8

Author(s):

Moloud ArianMaram ◽

Mahmoud Ghiasi ◽

Hassan Ghassemi ◽

Hamid Reza Ghafari

Keyword(s):

Boundary Element Method ◽

Boundary Element ◽

Basic Equation ◽

Pressure Coefficient ◽

Three Dimensional ◽

Computer Code ◽

Hydrodynamic Analysis ◽

B Spline ◽

Coefficient Distribution ◽

In this paper, two different 3D hydrofoils with profiles NACA0012 are simulated in the potential flow. Boundary element method (BEM) and nonuniform rational B-spline (NURBS) are coupled to reduce error and increase accuracy. The computer code is developed in different submergence depths (d), flow velocities (U), and various angles of attack (AoA), and the pressure is obtained by NURBS formulation. The pressure on a 3D hydrofoil with NACA412 profile iscompared with other existing methods. The validity of result is revealed. The accuracy of the results is acceptable. The competition of the two models’ results indicates that the increasing chord length leads to increase in C p min , and the decrease in depth and angle of attack leads to the growing value of C p min . Moreover, when the flow velocity is changed, the changes of potential and pressure coefficient distribution do not follow the specific trend. NURBS is a basic equation in different CAD packages because it is able to mesh surfaces. This study demonstrates that this algorithm does mesh surface of high quality, so it can be developed to generate mesh on the submerged three-dimensional bodies .

Excitation of secondary Love and Rayleigh waves in a three-dimensional sedimentary basin evaluated by the direct boundary element method with normal modes

Geophysical Journal International ◽

10.1046/j.1365-246x.1998.00477.x ◽

1998 ◽

Vol 133 (2) ◽

pp. 260-278 ◽

Cited By ~ 9

Author(s):

Ken Hatayama ◽

Hiroyuki Fujiwara

Keyword(s):

Boundary Element Method ◽

Boundary Element ◽

Rayleigh Waves ◽

Sedimentary Basin ◽

Three Dimensional ◽

Normal Modes ◽

Boundary element method in numerical study of three-dimensional Stokes flows in channels of arbitrary shape

Proceedings of the Mavlyutov Institute of Mechanics ◽

10.21662/uim2012.1.018 ◽

2012 ◽

Vol 9 (1) ◽

pp. 94-97

Author(s):

Yu.A. Itkulova

Keyword(s):

Boundary Element Method ◽

Boundary Element ◽

Cross Section ◽

Numerical Study ◽

Three Dimensional ◽

Cylindrical Tube ◽

Variable Cross Section ◽

Variable Cross ◽

Periodic Flows ◽

In the present work creeping three-dimensional flows of a viscous liquid in a cylindrical tube and a channel of variable cross-section are studied. A qualitative triangulation of the surface of a cylindrical tube, a smoothed and experimental channel of a variable cross section is constructed. The problem is solved numerically using boundary element method in several modifications for a periodic and non-periodic flows. The obtained numerical results are compared with the analytical solution for the Poiseuille flow.

3D simulation of emulsion flow using the boundary element method on the heterogeneous computational systems

Proceedings of the Mavlyutov Institute of Mechanics ◽

10.21662/uim2012.1.028 ◽

2012 ◽

Vol 9 (1) ◽

pp. 142-146

Author(s):

O.A. Solnyshkina

Keyword(s):

Boundary Element Method ◽

Boundary Element ◽

Three Dimensional ◽

Reynolds Numbers ◽

Problem Size ◽

Low Reynolds Numbers ◽

Infinite Domains ◽

The Matrix ◽

Computational Systems ◽

In this work the 3D dynamics of two immiscible liquids in unbounded domain at low Reynolds numbers is considered. The numerical method is based on the boundary element method, which is very efficient for simulation of the three-dimensional problems in infinite domains. To accelerate calculations and increase the problem size, a heterogeneous approach to parallelization of the computations on the central (CPU) and graphics (GPU) processors is applied. To accelerate the iterative solver (GMRES) and overcome the limitations associated with the size of the memory of the computation system, the software component of the matrix-vector product

Efficient evaluation of integrals in three-dimensional boundary element method using linear shape functions over plane triangular elements

Applied Mathematical Modelling ◽

10.1016/0307-904x(92)90046-6 ◽

1992 ◽

Vol 16 (6) ◽

pp. 282-290 ◽

Cited By ~ 6

Author(s):

Rajesh Srivastava ◽

Dinshaw N. Contractor

Keyword(s):

Boundary Element Method ◽

Boundary Element ◽

Three Dimensional ◽

Shape Functions ◽

Dimensional Boundary ◽

Triangular Elements ◽

Linear Shape ◽

Reduced-Order Modeling of Unsteady Flows About Complex Configurations Using the Boundary Element Method

Journal of Fluids Engineering ◽

10.1115/1.1511166 ◽

2002 ◽

Vol 124 (4) ◽

pp. 988-993 ◽

Cited By ~ 16

Author(s):

V. Esfahanian ◽

M. Behbahani-nejad

Keyword(s):

Boundary Element Method ◽

Boundary Element ◽

Three Dimensional ◽

Unsteady Flows ◽

Reduced Order Modeling ◽

Element Formulation ◽

Reduced Order Models ◽

Reduced Order ◽

Naca 0012 ◽

An approach to developing a general technique for constructing reduced-order models of unsteady flows about three-dimensional complex geometries is presented. The boundary element method along with the potential flow is used to analyze unsteady flows over two-dimensional airfoils, three-dimensional wings, and wing-body configurations. Eigenanalysis of unsteady flows over a NACA 0012 airfoil, a three-dimensional wing with the NACA 0012 section and a wing-body configuration is performed in time domain based on the unsteady boundary element formulation. Reduced-order models are constructed with and without the static correction. The numerical results demonstrate the accuracy and efficiency of the present method in reduced-order modeling of unsteady flows over complex configurations.