A three-dimensional numerical approach on water entry of a horizontal circular cylinder using the volume of fluid technique

Abstract A series of numerical experiments have been carried out on the water entry problem of three-dimensional multi-degree-freedom cylinders. The circular cylinder was released above the water with a specified inclined angle and velocity at entry. The hydrodynamics of the water entry problem have been investigated numerically. The Piecewise Linear Interface Calculation (PLIC) schemes have been applied in conjunction with the Volume of Fluid (VOF) method to capture the interface. Overset meshes have been adopted to handle the moving object. The numerical model is built on the framework of OpenFOAM which is an open-source C++ toolbox. Numerical results have been obtained. Transient flow and pressure distributions have been generated. The presence of air entrapment which has been reported experimentally has also been confirmed in the numerical solution. The fluid physics of the oblique water entry problem such as the formation and development of the air entrapment has been explored. The transient positions and inclined angles of the moving circular cylinder have been found to be in good agreement with the experimental results. Parametric studies have been performed with major findings reported.

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Water Entry and Exit of a Horizontal Circular Cylinder

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

10.1115/omae2005-67311 ◽

2005 ◽

Cited By ~ 5

Author(s):

Xinying Zhu ◽

Odd M. Faltinsen ◽

Changhong Hu

Keyword(s):

Free Surface ◽

Circular Cylinder ◽

Surface Deformation ◽

Vertical Motion ◽

Water Entry ◽

The Body ◽

Computational Domain ◽

Entry And Exit ◽

Constrained Interpolation ◽

Horizontal Circular Cylinder

This paper describes the fully nonlinear free-surface deformations of initially calm water caused by water-entry and water-exit of a horizontal circular cylinder with both forced and free vertical motions. This has relevance for marine operations as well as for the ability to predict large amplitude motions of floating sea structures. A new numerical method called the CIP (Constrained Interpolation Profile) method is used to solve the problem. In this paper, the circular cylinder and free surface interaction is treated as a multiphase problem, which has liquid (water), gas (air) and solid (circular cylinder) phases. The flow is represented by one set of governing equations, which are solved numerically on a non-uniform, staggered Cartesian grid by a finite difference method. The free surface as well as the body boundary is immersed in the computational domain. The numerical results of the water entry and exit force, the free surface deformation and the vertical motion of the cylinder are compared with experimental results, and favorable agreement is obtained.

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Water Entry and Exit of a Horizontal Circular Cylinder

Journal of Offshore Mechanics and Arctic Engineering ◽

10.1115/1.2199558 ◽

2006 ◽

Vol 129 (4) ◽

pp. 253-264 ◽

Cited By ~ 48

Author(s):

Xinying Zhu ◽

Odd M. Faltinsen ◽

Changhong Hu

Keyword(s):

Free Surface ◽

Circular Cylinder ◽

Surface Deformation ◽

Vertical Motion ◽

Water Entry ◽

The Body ◽

Computational Domain ◽

Entry And Exit ◽

Constrained Interpolation ◽

Horizontal Circular Cylinder

In this paper we describe the fully nonlinear free-surface deformations of initially calm water caused by the water entry and water exit of a horizontal circular cylinder with both forced and free vertical motions. Two-dimensional flow conditions are assumed in the study. This has relevance for marine operations as well as for the ability to predict large amplitude motions of floating sea structures. A new numerical method called the CIP (Constrained Interpolation Profile) method is used to solve the problem. In this paper, the circular cylinder and free surface interaction is treated as a multiphase problem, which has liquid (water), gas (air), and solid (circular cylinder) phases. The flow is represented by one set of governing equations, which are solved numerically on a nonuniform, staggered Cartesian grid by a finite difference method. The free surface as well as the body boundary is immersed in the computational domain. The numerical results of the water entry and exit force, the free surface deformation and the vertical motion of the cylinder are compared with experimental results, and favorable agreement is obtained.

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3D Volume-of-Fluid (VOF) Based Simulation of Water Impact Problem Using Navier-Stokes Computations

Volume 1A: Symposia, Part 2 ◽

10.1115/ajkfluids2015-06153 ◽

2015 ◽

Author(s):

Van-Tu Nguyen ◽

Warn-Gyu Park

Keyword(s):

Stokes Equations ◽

Three Dimensional ◽

Free Surface Flow ◽

Volume Of Fluid ◽

Water Entry ◽

Surface Flow ◽

Dam Break ◽

Navier Stokes ◽

Water Impact ◽

Impact Problem

In this paper, a three-dimensional (3D) numerical investigation of dam-break and water entry problems with emphasis on the water impact loading is presented. Flow fields of incompressible viscous fluids are solved using unsteady Navier-Stokes equations (NS). Pseudo-time derivatives are introduced into the equations to improve computational efficiency. The interface between two phases is tracked using a volume-of-fluid (VOF) interface tracking algorithm developed in a generalized curvilinear coordinate system. The accuracy and capability of the numerical model for free surface flow simulations are demonstrated by using experiments of the dam-break flow over a horizontal dry bed. The water impact problem has been analyzed by free falling water entry of a hemisphere and a cone. Comparisons between the obtained solutions, the experimental data and the results of other numerical simulations in the literature are presented exhibiting good agreement.

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