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This study aims to propose a numerical modeling procedure for response analysis of elastic body floating in water and submitted to regular waves. An equivalent simplified mechanical single-degree-of-freedom system allowing to reproduce the heave movements is first developed, then the obtained lumped characteristics are used for elastic analysis of the floating body in heave motion.

First, a two-dimensional numerical model of a rigid floating body in a wave tank is implemented under DualSPHysics, an open source computational fluid dynamics (CFD) code based on smoothed particle hydrodynamics method. Then, the obtained results are exploited to derive an equivalent mechanical mass-spring-damper model. Finally, estimated equivalent characteristics are used in a structural finite element modeling of the considered body assuming elastic behavior.

Obtained results concerning the floating body displacements are represented and validated using existing experimental data in the literature. Wave forces acting on the body are also evaluated. It was found that for regular waves, it is possible to replace the complex CFD refined model by an equivalent simplified mechanical system which makes easy the use of structural finite element analysis.

The originality of this work lies in the proposed procedure to evaluate the mechanical properties of the equivalent elastic system. This allows to couple two different software tools and to take advantages of their features.

The paper aims to present a numerical modeling procedure for the analysis of liquid sloshing in a flexible tank subjected to an external excitation, with taking into account the effects of fluid–structure interaction (FSI).

A numerical model based on coupling a two-phase flow solver and an elastic solid solver is developed in OpenFOAM code. The Arbitrary Lagrangian–Eulerian formulation is adopted for the two-phase Navier–Stokes equations in a moving domain. The volume of fluid (VOF) method is applied for the air–liquid interface tracking. The finite volume method is used for the spatial discretization of both the fluid and the structure dynamics equations. The FSI coupling problem is solved by an explicit coupling scheme. The model is validated for linear and nonlinear sloshing cases. Then, it is used to analyze the effects of the liquid sloshing on the dynamic response of the tank and the effects of the tank flexibility on the liquid sloshing.

The obtained results show that the flexibility of the tank walls amplifies the amplitude of the sloshing and increases the fluctuation period of the air–liquid interface. Furthermore, it is found that the bending moment acting on the tank walls may be underestimated when rigid walls assumption is adopted as usually done in sloshing tank modeling. Also, tank walls flexibility causes a phase shift in the free surface dynamic response.

A review of previous studies on liquid sloshing in flexible tanks revealed that FSI effects have not been clearly and comprehensively analyzed for large-amplitude liquid sloshing. Many physical and numerical aspects of this problem still require clarifications and enhancements. The added value of the present work and its originality lie in the investigation of large-amplitude liquid sloshing in flexible tanks by using a staggered coupling approach. This approach is carried out by an original combination of a linear solid solver with a two phase fluid solver in OpenFOAM code. In addition, FSI effects on some response quantities, identified and analyzed herein, have not been found in the previous works.

The purpose of this paper is to present results of an experimental program conducted on manufacturing process of crushed sand. The aim of the research is to propose an optimized approach which allows to fix, directly at the process stage, the rate of fines in the produced crushed sand.

In the first step of the study, samples of crushed sand are collected in situ, at each adjustment of the identified operating parameters. They are then analyzed in laboratory to retrieve especially the fines contents for each adjustment. These adjustments are conducted for all possible combinations of the extremum operating conditions of the parameters. In the second step of the study, the experimental design technique is applied to study the influence of the different factors, and to model the interaction between them. An expression is obtained and subjected to statistical tests, and then it is confronted to other experimental measures.

Parameters influencing the fines rates are identified and their effects are analyzed. The domain of variation of three predominant parameters is defined allowing to conduct in situ experiments with minimal incidence on the manufacturing disturbance. A mathematical model is proposed to quantify the crushed sand fines by analytical expression that takes into account the interaction between influencing parameters.

The conducted experiments provided new data that will help to enhance and to better set up the settings of the parameters influencing the rate of filler. The proposed expression constitutes a practical tool for the manufacturer to fix the operating parameters values that results in a desired target fines contents.

Modeling and optimization of the sand crushing plant, considered here as a case study, has not been attempted previously. The conducted experiments and the proposed mathematical model constitute an original work of this study.