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This paper aims to report the study of a fluid buoy system that includes wave effects, with particular emphasis on validating the numerical results with experimental data.

A fluid–solid coupled algorithm is proposed to describe the motion of a rigid buoy under the effects of waves. The Navier–Stokes equations are solved with the open-source finite volume package Code Saturne, in which a free-surface capture technique and equations of motion for the solid are implemented. An ad hoc experiment on a laboratory scale is built. A buoy is placed into a tank partially filled with water; the tank is mounted into a shake table and subjected to controlled motion that promotes waves. The experiment allows for recording the evolution of the free surface at the control points using the ultrasonic sensors and the movement of the buoy by tracking the markers by postprocessing the recorded videos. The numerical results are validated by comparison with the experimental data.

The implemented free-surface technique, developed within the framework of the finite-volume method, is validated. The best-obtained agreement is for small amplitudes compatible with the waves evolving under deep-water conditions. Second, the algorithm proposed to describe rigid-body motion, including wave analysis, is validated. The numerical body motion and wave pattern satisfactorily matched the experimental data. The complete 3D proposed model can realistically describe buoy motions under the effects of stationary waves.

The novel aspects of this study encompass the implementation of a fluid–structure interaction strategy to describe rigid-body motion, including wave effects in a finite-volume context, and the reported free-surface and buoy position measurements from experiments. To the best of the authors’ knowledge, the numerical strategy, the validation of the computed results and the experimental data are all original contributions of this work.

The present work is an experimental and numerical study of a sloshing problem including baffle effects. The purpose of this paper is to assess the numerical behavior of a Lagrangian technique to track free surface flows by comparison with experiments, to report experimental data for sloshing at different conditions and to evaluate the effectiveness of baffles in limiting the wave height and the wave propagation.

Finite element simulations performed with a fixed mesh technique able to describe the free surface evolution are contrasted with experimental data. The experiments consist of an acrylic tank of rectangular section designed to attach baffles of different sizes at different distance from the bottom. The tank is filled with water and mounted on a shake table able to move under controlled horizontal motion. The free surface evolution is measured with ultrasonic sensors. The numerical results computed for different sloshing conditions are compared with the experimental data.

The reported numerical results are in general in good agreement with the experiments. In particular, wave heights and frequencies response satisfactorily compared with the experimental data for the several cases analyzed during steady state forced sloshing and free sloshing. The effectiveness of the baffles increases near resonance conditions. From the set of experiments studied, the major reduction of the wave height was obtained when larger baffles were positioned closer to the water level at rest.

Model validation: evaluation of the effectiveness of non-massive immersed baffles during sloshing.

The value of the present work encompass the numerical and experimental study of the effect of immersed baffles during sloshing under different imposed conditions and the comparison of numerical results with the experimental data. Also, the results shown in the present work are a contribution to the understanding of the role in the analysis of the proposed problem of some specific aspects of the geometry and the imposed motion.

An integrated formulation for the analysis of casting processes is presented in this work. This model involves the description of the evolution and the coupled interactions of the flow, thermal and mechanical fields occurring during the liquid‐solid transformation of the solidifying metal. The corresponding discretized formulation is solved in the context of a fixed‐mesh finite element method. Numerical results applying this methodology in two cylindrical casting specimens are first presented to assess the influence of different phenomena occurring during the process. Moreover, these simulations are compared with available experimental data.

This work is devoted to the experimental analysis, numerical modelling and validation of ice melting processes.

The thermally coupled incompressible Navier‐Stokes equations including water density inversion and isothermal phase‐change phenomena are assumed as the governing equations of the problem. A fixed‐mesh finite element formulation is proposed for the numerical solution of such model. In particular, this formulation is applied to the analysis of two different transient problems.

The numerical results computed with the finite element formulation have been found to be very similar to the corresponding predictions, also obtained in this study, provided by a finite volume enthalpy‐based technique. Both numerical results, in turn, satisfactorily approached the available experimental measurements expressly conducted in the context of this work for validation purposes.

They are mainly due to some model simplifications (e.g. no volume changes are considered during the solid‐liquid transformation) and to the inherent difficulties associated with the experimental measurements.

This study may be relevant for a better understanding of the phenomena occurring in different engineering applications involving phase‐change in water: food freezing, ice formation in pipes, freezing/melting processes in soils, ice growth in plane wings, etc.

The study is mainly focused on the validation of the numerical predictions obtained with the finite element formulation mentioned above with other results provided by a well‐known finite volume technique and, in addition, with available laboratory measurements carried out in the context of this work.

The modelling of steady‐state natural and mixed convection in obstructed channels is presented. The two‐dimensional numerical analysis is carried out with a finite element thermally coupled incompressible flow formulation written in terms of the primitive variables of the problem and solved via a generalized streamline operator technique. Natural convection is studied in several vertical channel configurations for a wide range of Rayleigh numbers while mixed convection is analysed in a horizontal channel with a built‐in rectangular cylinder for different Reynolds and Grashof numbers. The results obtained in this work are validated with available experiments and other existing numerical solutions.

The present work is a numerical study of a breaking dam problem. The purpose of this paper is to assess the effect of turbulence and surface tension models in the prediction of the interface position in a long-term analysis. Additionally, dimensional effects are analyzed by carrying out both 2D and 3D simulations.

Finite volume simulations performed with the different models are compared between them and contrasted with numerical results computed using other numerical techniques and experimental data.

The reported numerical results are in general in good agreement with experimental results available in the literature. They are also consistent with numerical solutions of other authors obtained using different numerical techniques. The results show that the laminar simulations exhibit strong mesh size dependency, while the turbulence models seem to help in producing mesh-independent solutions. Surface tension modeling does not seem to play a relevant role in the interface evolution.

Model validation.

The value of the present work encompass the comparison of different flow conditions used to simulate a free surface problem and their validation by contrasting numerical results with experiments. Also, the results shown in the present work are a contribution to the understanding of the role of some specific aspects of the models in the simulation of the proposed problem.

The purpose of this paper is to present a 2D numerical simulation of natural convection and phase‐change of succinonitrile in a horizontal Bridgman apparatus. Three different heat transfer mechanisms are specifically studied: no growth, solidification and melting.

The analysis is carried out with a preexisting thermally coupled fixed‐mesh finite element formulation for generalized phase‐change problems.

In the three cases analyzed, the predicted steady‐state liquid‐solid interfaces are found to be highly curved due to the development of a primary shallow cell driven by the imposed furnace temperature gradient. In the no growth case, the heating and cooling jackets remain fixed and, therefore, a stagnant liquid‐solid interface is obtained. On the other hand, the phase transformation in the solidification and melting cases is, respectively, controlled by the forward and backward movement of the jackets. In these last two growth conditions, the permanent regime is characterized by a moving liquid‐solid interface that continuously shifts with the same velocity of the jackets. The numerical results satisfactorily approach the experimental measurements available in the literature.

The numerical simulation of the no growth, solidification and melting cases in a horizontal Bridgman apparatus using a finite element based formulation is the main contribution of this work. This investigation does not only provide consistent results with those previously computed via different numerical techniques for the no growth and solidification conditions but also reports on original numerical predictions for the melting problem. Moreover, all the obtained solid‐liquid interfaces are validated with experimental measurements existing in the literature.