Fluid Structure Interaction of 2D Objects through a Coupled KBC-Free Surface Model

In this study, the capabilities of a coupled KBC-free surface model to deal with fluid solid interactions with the slamming of rigid obstacles in a calm water tank were analyzed. The results were firstly validated with experimental and numerical data available in literature and, thereafter, some additional analyses was carried out to understand the main parameters’ influence on slamming coefficient. The effect of grid resolution and Reynolds number were firstly considered to choose the proper grid and to present the weak impact of such a non-dimensional number on process evolution. Hence, the influence of Froude number on fluid-dynamics quantities was pointed out considering vertical impacts of both cylindrical, as in the references, and ellipsoidal obstacles. Different formulations of slamming coefficient were used and compared. Results are pretty encouraging and they confirm the effectiveness of lattice Boltzmann model to deal with such a problem. This leaves the door open to additional improvements addressed to the study of free buoyant bodies immersed in a fluid domain.

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An Improved Single-Phase Free-Surface Lattice Boltzmann Model with Surface Tension and Wall Adhesion

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.300-301.1062 ◽

2013 ◽

Vol 300-301 ◽

pp. 1062-1066

Author(s):

Yang Yu ◽

Li Chen ◽

Jian Hua Lu ◽

Guo Xiang Hou

Keyword(s):

Surface Tension ◽

Free Surface ◽

Lattice Boltzmann ◽

Single Phase ◽

Lattice Boltzmann Model ◽

Surface Model ◽

Two Phase ◽

Surface Method ◽

Free Surface Model ◽

Boltzmann Model

Free-surface model with surface tension and wall adhesion(wetting) is a very efficient technique to simulate two-phase flows with high density and viscosity ratios, such as etching and casting processes. In this paper, a conservative surface tension and wall adhesion model based on lattice Boltzmann single-phase free-surface method is proposed. The effectiveness of the model is demonstrated by simulating the flows induced by wall adhesion and surface tension, and filling processes in a 2D cavity.

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A lattice-Boltzmann free surface model for injection moulding of a non-Newtonian fluid

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2019.0407 ◽

2020 ◽

Vol 378 (2175) ◽

pp. 20190407 ◽

Cited By ~ 1

Author(s):

Daniele Chiappini

Keyword(s):

Free Surface ◽

Lattice Boltzmann ◽

Injection Moulding ◽

Soft Matter ◽

Density Ratio ◽

Acrylonitrile Butadiene Styrene ◽

Free Surface Flow ◽

Surface Flow ◽

Surface Model ◽

Free Surface Model

The aim of this work is to present a lattice Boltzmann (LB) model devoted to dealing with non-Newtonian free surface flow. The combination of LB solver with a free-surface model allows dealing with multiphase flows where the density ratio in between the two considered phases is so high that the lighter phase can be neglected. For this particular set of multiphase models, the interface between the two phases is numerically reconstructed and transported via a diffusion equation. Moreover, the application of a Carreau approach for viscosity modelling allows the introduction of effects related to shear stress on fluid flow evolution. Two different non-Newtonian silicon-like materials have been considered here, namely the polystyrene and acrylonitrile butadiene styrene. Here, the author, after the mandatory model validation with a reference configuration, presents some applications of injection moulding for two different test-cases: the former is the injection in a labyrinth-like gasket, whereas the latter is the injection in a porous media. This article is part of the theme issue ‘Fluid dynamics, soft matter and complex systems: recent results and new methods’.

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