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The purpose of this paper is to implement the numerical analysis based on finite volume method to compare the effects of stress-jump (SJ) and stress-continuity (SC) conditions on flow structure around and through a porous circular cylinder.

In this study, a steady flow of a viscous, incompressible fluid around and through a porous circular cylinder of diameter “D,” using Darcy-Brinkman-Forchheimer’s equation in the porous region, is discussed. The SJ condition proposed by Ochoa-Tapia and Whitaker is applied at the porous-fluid interface and compared with the traditional interfacial condition based on the SC condition in fluid and porous media. Equations with the relevant boundary conditions are numerically solved using a finite volume approach. In this study, Reynolds and Darcy numbers are varied within the ranges of 1 < Re < 40 and 10-7 < Da < 10-2, respectively, and the porosities are e=0.45, 0.7 and 0.95.

Results show that the SJ condition leads to a much smaller boundary layer within porous medium near the interface as compared to the SC condition. Two interfacial conditions yield similar results with decrease in porosity.

There is no published research in the literature about the effects of important parameters, such as Porosity and Darcy numbers on different fluid-porous interface conditions for a porous cylinder and comparison the effects of SJ and SC conditions on flow structure around and through a porous circular cylinder.

In the early 1980's in the context of a deep recession a number of commentators talked of major changes which heralded the demise of trade unionism (Brown, 1984), (Massey and Miles, 1984). Towards the mid‐1980's the debate became polarised between those who argued for change (Basset, 1986) versus those stressing continuity (MacInnes, 1987). Towards the end of the 1980's a more sophisticated analysis suggested that there had been both change and continuity (Kelly, 1991), however, the emphasis was largely upon continuity in view of the surveys at that time (Legge, 1988). The issues from the mid‐1980's have become more complex due to terms such as the “New Industrial Relations” (Dunn, 1990; Keenoy, 1991), “Human Resource Management” (Guest, 1987, 1989, 1991; Storey, 1989; Keenoy, 1991), and “Japanization” (IRJ, 1988; Oliver and Wilkinson, 1988) which suggest a transformation of industrial relations.

The main purpose of this paper is to present and compare two different models for bubble growth and foam formation and to conduct a thorough assessment in terms of their numerical implementation and prediction accuracy.

The two models are assessed and validated against experimental measurements. The first model is known as a single bubble growth model and treats the foaming process as a single bubble growing in a large pool with enough gas available for growth, while the second model (cell model) takes into account the finiteness of gas supply availability as well as the effects of surrounding bubbles. The models are based on the application of the conservation of continuity and momentum principles and on constitutive equations to represent the viscosity of the melt. The models are numerically implemented using a finite difference scheme and their predictions are compared against experimental measurements.

The results demonstrate that the single bubble model predicts an infinite bubble growth with time due to the assumption of unlimited supply of the blowing agent. Meanwhile the cell model gives an equilibrium bubble size because it accounts for gas depletion. From this work, it was concluded that the cell model is the best model that adequately describes experimental data.

The problem of bubble growth and foam formation is of great importance in the process industry as it plays a key role in diverse technological fields such as the production of foamed plastics.

The findings here are important for the appropriate modeling of bubble growth and foam formation and for scheduling and optimizing the process. A simple model will suffice for the early stage of the process while a cell model is more appropriate for the entire duration of the process.

The paper aims to examine the theory that trade unions' functions in a transitional economy are characterised by “path dependency”.

The research is based on case studies of employment relations in enterprises operating in Moldova. The approach is realist (critical materialism). An ethnographic approach is taken to analysing social relations in three locally and foreign‐owned companies in the clothing sector. The case studies explore union responses to managerially driven re‐structuring.

The research established that these forms of trade unionism exhibit considerable heterogeneity within continued commitment to their welfare functions. This may indicate that the “integrating collectivist” form does not presage a new “path” for Moldovan trade unionism but does demonstrate the bounded diversity within the existing paradigm.

The research studies the unionised sector. Future research might look into non‐unionised Greenfield sites. The research has established that networks are being reconstructed between workers. Whether this will generate a new path for unionism and challenge managerial control remains to be established.

Findings indicate that the welfare function corresponds to workers' historic expectations and may provide a base for unions from which other, more conflictual activity may be conducted. Conversely, it suggests that attention to local norms is essential for employer's strategies aimed at combining efficiency with quality and fairness.

The research unveils the failures of employment relations' institutions to address women workers needs in the area calling for all stakeholders to act on this issue to prevent negative consequences (poverty, migration, turnover).

Institutionalist research on transition has stressed continuity and neglected agency. This research asks how far actors have wished and have been able to reconstitute institutions across time. To this end it has established dialogues with workers and managers making comprehensive sense of their views. Findings are relevant to unionists and employers as well as other stakeholders in transformation societies.

The purpose of this paper is to study steady, laminar, and two-dimensional flow around and through a porous diamond cylinder.

The governing equations are written for two zones: the clear fluid zone and the porous zone. For the porous zone, the modified Navier-Stokes equations, including Darcy, Brinkman, and Forcheimer terms are used. The governing equations are solved numerically using a finite volume approach.

It was found that as the apex angle and Reynolds number decreases the wake length decreases and the separation is delayed.

There is no published research in the literature about flow around and into porous diamond cylinders to study the effect of important parameters, such as apex angle, Darcy number, and Reynolds number.

The purpose of this paper is to investigate the unsteady flow past through a permeable diamond-shaped cylinder and to study the effects of the aspect ratios and Darcy numbers of the cylinder.

The lattice Boltzmann method with D2Q9 lattice model was used to simulate the unsteady flow through permeable diamond-shaped cylinders. The present numerical method is validated against the available data.

The key findings are that increasing the permeability enhances the suppression of vortex shedding, and that the Strouhal number is directly proportion to the Darcy number, Reynolds number and the aspect ratio of the porous cylinder.

The present study considers unsteady laminar flow past through single permeable diamond-shaped cylinder. According to the authors’ knowledge, very few studies have been found in this field. The present findings are novel and original, which in turn can attract wide attention and citations.

A C° finite element formulation for flexure‐membrane coupling behaviour of an unsymmetrically laminated plate based on a higher‐order displacement model and three‐dimensional state of stress and strain is presented. This theory incorporates the more realistic non‐linear variation of displacements through the plate thickness, thus eliminating the use of a shear correction coefficient. The discrete element chosen is a nine‐noded quadrilateral with 12 degrees of freedom per node. The computer program developed incorporates the realistic prediction of interlaminar stresses from equilibrium equations. The present solution for deflection and stresses is compared with those obtained using three‐dimensional elasticity theory, another higher‐order shear deformation theory and Mindlin theory. In addition, numerical results for unsymmetric sandwich plates are presented for future reference.

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.

Two displacement‐based higher‐order models are analysed. The in‐plane displacements are a cubic variation of the thickness coordinate for the first model. The other cubic model is simplified without second order term. In the beginning, comparisons are realised in exact solution cases. Then to improve the accuracy of the above process, computations of these two models are compared to the measures of laminated complex beam bending experiments.

The purpose of this paper is to investigate and to assess the capabilities of the most common finite element (FE)‐based tools to deal with global‐local analysis. Two kinds of coupling were investigated: shell to shell and shell to solid.

The issue of connecting non‐matching FE global and local models, characterized by different mesh refinements and/or different element types, was addressed by introducing appropriate kinematic constraints on the nodes at the interfaces. The coupling techniques available in the three FE‐based codes (ABAQUS^®, NASTRAN^® and ANSYS^®), were assessed by applying them on a common numerical test case (non‐linear buckling analysis of a square plate). Results of the global‐local simulations were compared to the results obtained for relevant reference solutions.

The continuity of displacements and stresses across the interface between global and local models and the influence of the presence of the local model on the global model solution were used as parameters to test the quality of the results. It was observed that the tools implemented in the different codes provide different results. The results characterized by a higher quality were found by using the Multi Point Constraint available in ABAQUS^®.

When dealing with complex structures, multi‐scale (global‐local) approaches are commonly adopted to optimize the computational cost by increasing mesh refinements and/or introducing elements with different formulations in specific region of the structures identified as “local model”. In this paper an overview of the coupling tools available in the main commercial FE code is given.