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This paper aims to propose a three-phase interpenetrating continua model for the numerical simulation of water waves and porous structure interaction.

In contrast with one-fluid formulation or multi-component methods, each phase has its own characteristics, density, velocity, etc., and each point is occupied by all phases. First, the porous structure is modelled as a phase of continua with a penalty force adding on the momentum equation, so the conservation of mass is guaranteed without source terms. Second, the adaptive unstructured mesh modelling with P1DG-P1 elements is used here to decrease the total number of degree of freedom maintaining the same order of accuracy.

Several benchmark problems are used to validate the model, which includes the Darcy flow, classical collapse of water column and water column with a porous structure. The interpenetrating continua model is a suitable approach for water wave and porous structure interaction problem.

The interpenetrating continua model is first applied for the water wave and porous structure interaction problem. First, the structure is modelled as phase of non-viscous fluid with penalty force, so the break of the porous structure, porosity changes can be easily embedded for further complex studies. Second, the mass conservation of fluids is automatically satisfied without special treatment. Finally, adaptive anisotropic mesh in space is employed to reduce the computational cost.

A modelling approach of gas solid flow, considering different physical phenomenon such as fluid turbulence, particle turbulence and interparticle collision effects are presented. The approach is based on the two‐fluid model formulation where both phases are treated as continuum. This implies that the gas phase as well as the particle phase are weighted by their separate volumetric fractions. According to the experimental results and numerical simulations, the inter‐particle collision possesses a significant influence of turbulence level on particle transport properties in gas solid turbulent flow even for dispersed phase volume fraction (α<0.01). Comparisons in predictions have been depicted with inclusion of interparticle collision effect in the equation of particle turbulent kinetic energy and with exclusion of this effect. Experimental research has been conducted in a thermal power plant depicting higher erosion resistance of noncircular square sectioned coal pipe bends in comparison with those with circular cross section, the salient features of the experimental work are presented in this paper. Experiments have been conducted to determine, pressure drop in straight and curved portions of conduits conveying air coal mixtures in a thermal power plant. Validation of this experimental data with numerical predictions have been presented.

The purpose of this paper is to present a numerical and mathematical model of a moulding process of a dry electrical transformer. Moreover, the calculated results are reported and compared with experimental measurements.

An experimental rig, for carrying out and monitoring a moulding process, has been designed and built. Two experiments were preformed. First was an isothermal experiment in which an analog liquid was used. The second experiment was a non‐isothermal one in which an epoxy resin was used. For the rig geometry, the numerical mesh, with the use of the commercial code Gambit, was built. All necessary physical properties, including viscosity, surface tension and contact angle of fluids used in the experiments were measured.

The Euler approach for modelling multiphase flow with a free surface is addressed in the presented work. Comparison of the computational results with measurements on the designed experimental rig revealed good agreement. Comparison was carried out through measurements of free surface characteristic features captured with a digital camera and through temperature measurements for the nonisothermal case. Richardson extrapolation method was successfully applied to estimate the numerical discretisation error, proving that a grid independent solution was obtained.

This paper is useful for researchers and industrialists involved in the modelling of moulding processes, giving guidance on the available mathematical models appropriate for this kind of problem. Moreover, it provides valuable information as to how to perform validation and verification procedures for such real‐life processes.

The purposes of this paper are to review the progress of and conclude the trend for paint thickness simulation for painting robot trajectory planning.

This paper compares the explicit function-based method and computational fluid dynamics (CFD)-based method used for paint thickness simulation. Previous research is considered, and conclusions with the outlook are drawn.

The CFD-based paint deposition simulation is the trend for paint thickness simulation for painting robot trajectory planning. However, the calculation of paint thickness resulting from dynamically painting complex surface remains to be researched, which needs to build an appropriate CFD model, study approaches to dynamic painting simulation and investigate the simulation with continuously changing painting parameters.

This paper illustrates that the CFD-based method is the trend for the paint thickness simulation for painting robot trajectory planning. Current studies have been analyzed, and techniques of CFD modeling have also been summarized, which is vital for future study.

The purpose of this study is to assess the performance of ANSYS Fluent^® and OpenFOAM^®, at their current state of development, to study the relevant bubbling fluidized bed (BFB) characteristics with Geldart A, B and D particles.

For typical Geldart B and D particles, both a three-dimensional cylindrical and a pseudo-two-dimensional arrangement were used to measure the bed pressure drop and solids volume fraction, the latter by digital image analysis techniques. For a typical Geldart A particle, specifically to examine bubbling and slugging phenomena, a 2 m high three-dimensional cylindrical arrangement of small internal diameter was used. The hydrodynamics of the experimentally investigated BFB cases were also simulated for identical geometries and operating conditions using OpenFOAM^® v6.0 and ANSYS Fluent^® v19.2 at identical mesh and numerical setups.

The comparison between experimental and simulated results showed that both ANSYS Fluent^® and OpenFOAM^® provide a fair qualitative prediction of the bubble sizes and solids fraction for freely-bubbling Geldart B and D particles. For Geldart A particles, operated in a slugging mode, the qualitative predictions are again quite fair, but numerical values of relevant slug characteristics (length, velocity and frequency) slightly favor the use of OpenFOAM^®, despite some deviations of predicted slug velocities.

A useful comparison of computational fluid dynamics (CFD) software performance for different fluidized regimes is presented. The results are discussed and recommendations are formulated for the selection of the CFD software and models involved.

The purpose of this paper is to compute the pressure drop through sudden expansions and contractions for two‐phase flow of oil/water emulsions.

Two‐phase computational fluid dynamics (CFD) calculations, using Eulerian–Eulerian model, are employed to calculate the velocity profiles and pressure drops across sudden expansions and contractions. The pressure losses are determined by extrapolating the computed pressure profiles upstream and downstream of the expansion/contraction. The oil concentration is varied over a wide range of 0‐97.3 percent by volume. The flow field is assumed to be axisymmetric and solved in two dimensions. The two‐dimensional equations of mass, momentum, volume fraction and turbulent quantities along with the boundary conditions have been integrated over a control volume and the subsequent equations have been discretized over the control volume using a finite volume technique to yield algebraic equations which are solved in an iterative manner for each time step. The realizable per phase k‐ ε turbulent model is considered to update the fluid viscosity with iterations and capture the individual turbulence in both the phases.

The contraction and expansion loss coefficients are obtained from the pressure loss and velocity data for different concentrations of oil–water emulsions. The loss coefficients for the emulsions are found to be independent of the concentration and type of emulsions. The numerical results are validated against experimental data from the literature and are found to be in good agreement.

The present computation could not use the surface tension forces and the energy equation due to huge computing time requirement.

The present computation could compute realistically the two‐phase pressure drop through sudden expansions and contractions by using a two‐phase Eulerian model and hence this model can be effectively used for industrial applications where two‐phase flow comes into picture.

The original contribution of the paper is in the use of the state‐of‐the‐art Eulerian two‐phase flow model to predict the velocity profile and pressure drop through industrial piping systems.

The average residence time of liquid flowing over the surface of a rotating cone was determined numerically. The development and propagation of the free surface flow was simulated using the volume of fluid (VOF) method. The numerical simulations were validated using laboratory experiments using soy‐oil as a model liquid, and approximate analytical solutions of the simplified governing equations. The numerical simulations revealed the importance of the cone rotation frequencies and the minor influence of the cone angles on the residence times. Higher liquid throughputs produced smaller residence times. As expected, an increasing cone size results in proportionally higher residence times. Furthermore, it was established that even for small cones with a characteristic diameter of, e.g. less than 1m, relatively high (∼1 kg/s) throughputs of liquid are possible. It appears that the combination of the decreasing layer thickness and the increasing size of the numerical grid cells with increasing radial cone coordinate hampers the numerical simulation of this system.

The purpose of this paper is to invite further consideration of how people experience documents. By offering a model from Reader Response theory – Louise Rosenblatt's Transactional Theory of Reading – as well as examples from research on numinous experiences with museum objects, the author hopes to open further avenues of information behavior studies about people and documents. The goal is to incorporate more aspects of lived experience and the aesthetic into practice with and research of documents.

Theoretical scope includes Louise Rosenblatt's Transactional Theory of Reading, John Dewey's concepts of transaction and experience and lived experience concepts/methods derived from phenomenology.

Rosenblatt's Transactional Theory explicates the continuum of reader response, from the efferent to the aesthetic, stating that the act of “reading” (experience) involves a transaction between the reader (person) and the text (document). Each transaction is a unique experience in which the reader and text continuously act and are acted upon by each other. This theory of reading translates well into the realm of investigating the lived experience of documents and in that context, a concrete example and suggested strategies for future study are provided.

This paper provides a holistic approach to understanding lived experience with documents and introduces the concept of person-document transaction. It inserts the wider notion of document into a more specific theory of reading, expanding its use beyond the borders of text, print and literature. By providing an example of real document experiences and applying Rosenblatt's continuum, the value of this paper is in opening new avenues for information behavior inquiries.

This paper explores the domain of the symbolic imaginary to comprehend the mechanisms and effects of neoliberal deregulation (anomie) and reckless capital accumulation within and external to the US imperial core with special emphasis on the war on terror, the figure of the suicide bomber, and the internal manifestations of social liquidation in the appearance of the rampage shooter. The concept of the piacular developed by Durkheim is expanded to demonstrate the contrast between the “variable” or human forms of terror with “constant” or mechanized form of the piacular as it appears in the form of the unmanned aerial vehicle or drone. The apparently disconnected image of the drone flying around up there somewhere in the clouds is intimately connected with seemingly unrelated phenomenon of mass murdering martyrs and fanatics down here on the ground. Lastly, the prospects for an anti-drone movement are touched upon and suggested as a fulcrum point from which to “touch” the synthetic point where terror, rampage, and revenge unify.

Unique to this paper is the development of a dialectical, formal, conceptual “geometry” rooted in Durkheim’s classic analysis of suicide for disclosing the hidden analogs obtaining in the relationship between suicide bombings and rampage shootings and their conceptual fusion in the form of the unmanned aerial vehicle or drone.

Capitalism linked to global defense and security operations produces its own terrifying nemeses as both causes and effects. Rather than something that has to be defeated, terror is an enemy that cannot be defeated but neither can it prevail against an empire. Likewise, the rampage shooter is not merely an individual in need of psychiatric care but a product of domestic policies that sacrifice everything for security and war. These two figures are “mirror opposites” or speculative doubles of one another, which when we attempt to comprehend the image of the seemingly unrelated drone machine what were find is the unexpected synthesis of the twin logics of terror and rampage at work in the sky.

If people hope to live in a society ruled democratically rather than imperial subjects they must know where to apply moral and political leverage. Suicidal bombers and lone shooters are definite problems, but focusing on the defects of individuals diverts the critical gaze from the larger problem of foreign policy, domestic austerity, and, perhaps, the war on the drone represents a unique opening within the aggregate system to push back against the abstract, imperial system of global and domestic hegemony.

This paper represents a new and unique synthesis of Durkheimian and interpretive sociologies with various strands of critical social theory providing new optics for the analysis of international terrorism, domestic mass murders, and the use of unmanned aerial vehicles in the wars on terror.

Purpose – The negotiated order branch of symbolic interaction used to examine the process by which welfare regulations were dramatically changed in which the forty-year old AFDC (Aid to Families with Dependent Children) was abandoned, and a new W-2 (Welfare Works) welfare reform effort was developed and socially negotiated with the Federal government and in the State of Wisconsin. We probe interactions within the mesodomain of four levels of actors: the Federal government; State-level government in both the executive and legislative branches; county-level government; and public and private welfare service delivery agencies.

Method – Qualitative, naturalistic, ten-year field study entailing interviews and archival analyses.

Findings – The reform effort involved the mutual constitution of the W-2 social structure and the social interactions that surrounded it through such strategies as negotiation, conflict, manipulation, coercion, exchange, bargaining, collusion, power brokering, and rhetoric, which were all circumscribed by and interpenetrated with the predecessor AFDC rule system. In turn, the welfare budget was reduced from $652m to $257m. We observed that the macro structure of welfare shaped the micro social actions of a variety of actors, and that micro social action by institutional entrepreneurs reconstituted structure of welfare policy in what proved to be a moving matrix.

Research implications – Implications were directed at extending and refining the negotiated order perspective.

Social implications – Given that the number of welfare recipients was reduced from 300,000 to 10,000, their fate in a weak economy was explored.

Originality – Chapter extends symbolic interaction concepts to examine a contested social domain.