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This paper presents a boundary element method (BEM) based on a subdomain approach for the solution of non‐Newtonian fluid flow problems which include thermal effects and viscous dissipation. The volume integral arising from non‐linear terms is converted into equivalent boundary integrals by the multi‐domain dual reciprocity method (MD‐DRM) in each subdomain. Augmented thin plate splines interpolation functions are used for the approximation of field variables. The iterative numerical formulation is achieved by viewing the material as divided into small elements and on each of them the integral representation formulae for the velocity and temperature are applied and discretised using linear boundary elements. The final system of non‐linear algebraic equations is solved by a modified Newton's method. The numerical examples include non‐Newtonian problems with viscous dissipation, temperature‐dependent viscosity and natural convection due to bouyancy forces.

The purpose of this paper is to perform the computational fluid dynamics (CFD) simulation with experimental validation to investigate the particle segregation effect in abrupt and smooth shapes circulating fluidized bed (CFB) risers.

The experimental investigations were carried out in lab-scale CFB systems and the CFD simulations were performed by using commercial software BARRACUDA. Special attention was paid to investigate the gas-particle flow behavior at the top of the riser with three different superficial velocities, namely, 4, 6 and 7.7 m/s. Here, a CFD-based noble simulation approach called multi-phase particle in cell (MP-PIC) was used to investigate the effect of traditional drag models (Wen-Yu, Ergun, Wen-Yu-Ergun and Richardson-Davidson-Harrison) on particle flow characteristics in CFB riser.

Findings from the experimentations revealed that the increase in gas velocity leads to decrease the mixing index inside the riser. Moreover, the solid holdup found more in abrupt riser than smooth riser at the constant gas velocity. Despite the more experimental investigations, the findings with CFD simulations revealed that the MP-PIC approach, which was combined with different drag models could be more effective for the practical (industrial) design of CFB riser. Well agreement was found between the simulation and experimental outputs. The simulation work was compared with experimental data, which shows the good agreement (<4%).

The experimental and simulation study performed in this research study constitutes an easy-to-use with different drag coefficient. The proposed MP-PIC model is more effective for large particles fluidized bed, which can be helpful for further research on industrial gas-particle fluidized bed reactors. This study is expected to give throughout the analysis of CFB hydrodynamics with further exploration of overall fluidization.

In this paper, a novel boundary element formulation for the deformation of a viscous 2D‐planar cylindrical geometry, immersed in a different viscous fluid and moving towards a rigid wall, is proposed for moderate Reynolds number, considering surface tension effects. The boundary integral formulation for Stokes flow inside and outside the geometry is represented in terms of a combined distribution of a single‐layer and a double‐layer potential of Green functions over the geometry surface. Additionally, non‐linear terms describing effects absent in pure Stokes flow, such as the time derivative of the velocity and inertia, are included. These effects lead to the appearance of domain integrals. Traditional dual reciprocity is applied in order to approximate these domain integrals by a series of particular solutions which are then transformed into boundary integrals. Augmented thin‐plate splines, i.e. r²log(r), plus three additional linear terms from a Pascal triangle expansion were chosen for the dual reciprocity approximation. In order to avoid the discretization of the rigid wall, and using the fact that the velocity on the wall must vanish due to the no‐slip condition, the fundamental solution was modified with a combination of image singularities including an image Stokeslet, a potential dipole and a Stokes‐doublet.

The purpose of this numerical work is to present and test a new approach for large-scale scalar advection (splicing) in large eddy simulations (LES) that use the linear eddy sub-grid mixing model (LEM) called the LES-LEM.

The new splicing strategy is based on an ordered flux of spliced LEM segments. The principle is that low-flux segments have less momentum than high-flux segments and, therefore, are displaced less than high-flux segments. This strategy affects the order of both inflowing and outflowing LEM segments of an LES cell. The new splicing approach is implemented in a pressure-based fluid solver and tested by simulation of passive scalar transport in a co-flowing turbulent rectangular jet, instead of combustion simulation, to perform an isolated investigation of splicing. Comparison of the new splicing with a previous splicing approach is also done.

The simulation results show that the velocity statistics and passive scalar mixing are correctly predicted using the new splicing approach for the LES-LEM. It is argued that modeling of large-scale advection in the LES-LEM via splicing is reasonable, and the new splicing approach potentially captures the physics better than the old approach. The standard LES sub-grid mixing models do not represent turbulent mixing in a proper way because they do not adequately represent molecular diffusion processes and counter gradient effects. Scalar mixing in turbulent flow consists of two different processes, i.e. turbulent mixing that increases the interface between unmixed species and molecular diffusion. It is crucial to model these two processes individually at their respective time scales. The LEM explicitly includes both of these processes and has been used successfully as a sub-grid scalar mixing model (McMurtry et al., 1992; Sone and Menon, 2003). Here, the turbulent mixing capabilities of the LES-LEM with a modified splicing treatment are examined.

The splicing strategy proposed for the LES-LEM is original and has not been investigated before. Also, it is the first LES-LEM implementation using unstructured grids.

The main purpose of this paper is to investigate drivers and barriers of climate change mitigation strategies (CCMS), their linkages and impact in Indian Iron and Steel Industry (IISI) in light of ninth sustainable development goal (building resilient infrastructure, promote sustainable industrialization and foster innovation).

To identify relevant drivers and barriers, a thorough literature review and opinions of industry experts were obtained. Utilizing Total Interpretive Structural Modeling (TISM), the selected drivers and barriers were modeled separately along with Cross Impact Matrix-multiplication Applied to Classification (MICMAC).

Pragmatic and cost-effective technology, less supply chain complexity, robust policy and legal framework were found to have the highest driving power over all the other drivers. Findings suggest political pressure as the most critical barrier in this study. The results from TISM and MICMAC analysis have been used to elucidate a framework for the understanding of policymakers and achieve top management commitment.

This paper will help researchers, academicians, industry analysts and policymakers in developing a systems approach in prioritizing CCMS in energy-intensive (coal dependent) iron and steel plants. The model outcomes of this work will aid operational research to understand the working principles in other industries as well.

To the best of authors' knowledge, there is paucity of reported literature for the drivers and barriers of CCMS in iron and steel industry. This paper can be considered a unique, first attempt to use data from developing nations like India to develop a model and explain relationships of the existing drivers and barriers of CCMS.

This study provides practical guidelines for public relations campaigns targeted at Arab and American audiences. The authors examine various cultural frameworks for conceptualizing differences and similarities in the Arab and American cultures. They conclude that both cultures suffer considerably from biases and stereotypes.

Our purpose in this paper is three‐fold. First, we shall briefly describe what is almost a truism— that is, the classical (especially the Greek) intellectual heritage of the Arab‐Islamic scholars upon which the latter, imbued by their young faith, developed their own comprehensive synthesis. Second, as part of that synthesis, we shall explore briefly the economic thought of a few early‐medieval Arab‐Islamic scholastics who extended that heritage and wrote on numerous issues of human concern, including economics. Those discourses took place during what is sometimes called the “golden age” of Islam — a period that coincided roughly with the so‐called Dark Age of Europe. Parenthetically, it might be noted that one of 20th century's most prominent economists, the late Joseph Schumpeter (1883–1950) had, unfortunately for the continuity and evolution of human intellectual tradition, declared that period as “the Great Gap,” representing “blank centuries,” during which nothing of significance to economics, or for that matter to any field, was said or written anywhere — as though there was a complete lacuna over intellectual evolution throughout the rest of the world (Schumpeter, 52, 74; see Ghazanfar, 1991). And finally, we will provide some evidence as to the historically influential linkages of the Arab‐Islamic thought, including economic thought, with the Latin‐European scholastics‐a phenomenon that facilitated the European intellectual evolution. An underlying theme of this paper is predicated on the premise that the classical tradition (i.e., Greek knowledge, though not exclusively) is part of a long historical continuum that represents the inextricably linked Judeo‐Christian‐and‐Islamic tradition of the West. This theme, though not common appreciated, is amply corroborated through the writings of well‐known scholars from the East and the West (see, for example, Durant, Haskins, Myers, O'Leary, Said, Sarton, Sharif, and others).

This paper aims to examine the functioning and organizational structure of the historic Andalusian water courts, institutions of Islamic origin whose basic model should be considered in light of the regulation of modern Islamic banking and finance.

The methodology of this study has been focused on the contextualization of al-Andalus during the European Middle Ages, highlighting its enormous contributions and implications in the creation of Western knowledge. In the same way, the ordinances of the Castilian-Aragonese kings, aimed at the persistence of the Andalusian water courts in the Southeast of Spain after the Muslim period, have been used as the main sources of reference.

This research has detected that the main features of the Andalusian water courts, i.e. integrity, democracy, transparency, credibility, moral authority or simplicity (among many others), can be conveniently replicated in the scope of the current Islamic banking and finance.

Several implications can be derived from this study: first, it highlights the total resilience of a regulatory model that “it was already there,” given by the history of the Andalusian civilization. This model will be always welcomed by the Muslim community in Western countries as it is a matter of regulating themselves according to the way their ancestors did. The main limitation faced by this research is the relative scarcity of original sources, which is justifiable given that most of the royal ordinances come from the 13th century, having unfortunately lost a good number of sources over time.

This paper seeks a feasible alternative to the controversy arising from the resolution of possible disputes in Islamic banking and finance taking into account that Western judges do not know (nor do they have to) the principles on which this discipline is based. The application of the historical Andalusian model would allow the creation of an independent jurisdiction, while subordinated to the established juridic power, without contravening the principle of “jurisdictional unity.” The last element that gives an added value to this research is spreading the achievements of the Andalusian culture and civilization, unjustly omitted by a great part of the existing literature.