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This paper aims to investigate the entropy generation due to magnetohydrodynamic natural convection flow and heat transfer in a porous enclosure filled with Cu-water nanofluid in the presence of viscous dissipation effect. The left and right walls of the cavity are thermally insulated. There are heated and cold parts, and these are placed on the bottom and top wall, respectively, whereas the remaining parts are thermally insulated.

The finite volume method is used to solve the dimensionless partial differential equations governing the problem. A comparison with previously published woks is presented and is found to be in an excellent agreement.

The minimization of entropy generation and local heat transfer according to different values of the governing parameters are presented in details. It is found that the presence of magnetic field has negative effects on the local entropy generation because of heat transfer and the local total entropy generation. Also, the increase in the heated part length leads to a decrease in the local Nusselt number.

This problem is original, as it has not been considered previously.

The purpose of this paper is to study the unsteady ferrofluid flow with a hot source helix inside a cavity under the impacts of a variable magnetic field by using the incompressible smoothed particle hydrodynamics method.

The governing equations are formulated by considering the basics of the magnetohydrodynamic and ferrohydrodynamics. Different locations of a variable magnetic source outside the geometry are investigated. The helical coils are extensively applied in the cooling and heating of air conditioners and heat pumps. Computations were carried out for different lengths of the heated helix (0.2 ≤ L_h ≤ 0.8), different locations of the magnetic source, (a = 0.5, b = −0.01), (a = 0.5, b = 1.01), (a = 1.01, b = 0.5), (a = −0.01, b = 0.5), different numbers of the inner helix (one helix, two helixes and three helixes) and different values of the nanoparticles volume fraction (0% ≤ ϕ ≤ 10%).

The outcomes of the investigations revealed that an increase in the lengths of a helix by 0.4 results in a reduction of the stream function by 25.60%. In addition, when the magnetic wire is located near the center of the right wall, the maximum values of the average Nusselt number are obtained while the smallest values of the average Nusselt number are given when the magnetic source is located near center of the top wall.

The novelty of this paper is investigating the natural convection flow from two different models of an inner hot helix inside a cavity with considering different locations of variable magnetic sources.

The Galerkin finite element method (FEM) based on the characteristic-based split (CBS) scheme is applied to simulate the nanofluid flow and thermal fields inside an inclined geometry filled by a heat-generating hydrodynamically and thermally anisotropic non-Darcy porous medium using the local thermal non-equilibrium model (LTNEM). Property of the hydrodynamic anisotropy is taken in both the Forchheimer coefficient and permeability and these tools are considered as functions of inclination of the principal axes. Also, the thermal conductivity for the porous phase is assumed to be anisotropic.

The Galerkin FEM based on the CBS scheme is applied to solve the partial differential equations governing the flow and thermal fields.

It is noted that the net rate of the heat transfer between the nanofluid and solid phases are influenced by variations of the anisotropic properties. Also, the system is reached to the thermal equilibrium state at H > 100. Further, the maximum nanofluid temperature is reduced by 12.27% when the nanoparticles volume fraction is varied from 0% to 4%.

This paper aims to study the nanofluid flow and heat transfer characteristics inside an inclined enclosure filled with a heat-generating, hydrodynamically and thermally anisotropic porous medium using the CBS scheme. The LTNEM is considered between the nanofluid and porous phases while the local thermal equilibrium model (LTEM) between the base fluid (water) and the nanoparticles (alumina) is taken into account. The Galerkin FEM is introduced to discretize the governing system of equations. Also, examine influences of the anisotropic properties (permeability, Forchheimer terms and thermal conductivity of the porous medium), inclination angle and nanoparticles volume fraction on the net rate of the heat transfer between the nanofluid and porous phases and on the local thermal non-equilibrium state is one of the concerns of this paper.

The purpose of this numerical paper is to investigate the simulation of an unsteady double diffusive natural convection in square enclosure filled with a porous medium with various boundary conditions in the presence of thermal radiation and chemical reaction effects.

In this study, the governing dimensionless equations were written using the Brinkman Forchheimer extended Darcy model. They are numerically solved by using finite difference method by applying adiabatic boundary condition in top surface. The bottom surface is maintained at uniform temperature and concentration and left and right vertical walls are cooled.

Results are presented by streamlines, isotherms, temperature and concentration contours profiles as well as the local Nusselt number and Sherwood numbers for different values of the governing parameters such as Darcy number, buoyancy ratio, Rayleigh number, thermal radiation parameter and chemical reaction parameter. It is found that that both of the local Nusselt and Sherwood numbers increase as the Rayleigh number, buoyancy ratio and Darcy number increase. Moreover, increasing the thermal radiation effects leads to a pronounced increase in the local Nusselt number, while the opposite behavior is displayed by the local Sherwood number. Furthermore, the local Sherwood number increases and the local Nusselt number decrease when the chemical reaction parameter increase.

The originality of this study is the square cavity with various boundary conditions filled with a porous medium with thermal radiation and chemical reaction effects.

The purpose of this paper is to deal with unsteady double diffusive natural convection in a square enclosure filled with a porous medium with various boundary condition effects in the presence of heat source or sink.

Finite difference method was employed to solve the dimensionless governing equations of the problem. The effects of governing parameters, namely, amplitude wave length ratio, dimensionless time parameter, Darcy number, buoyancy parameter and heat generation/absorption parameter on the streamlines, temperature and concentration contours, as well as Nusselt number and Sherwood number, were considered.

The sinusoidal variations of the temperature and concentration remove the singularities which appear in the case of fixed temperature and concentration.

The paper's results are validated by favorable comparisons with previously published results. The results of the problem are presented in graphical and tabular forms and discussed.

The purpose of this paper is to explore the emergence of sustainability governance through the unfolding hybridisation process between corporate governance and corporate social responsibility and the implications of this for understanding patterns in sustainability reporting over time.

The Gulf of Mexico oil spill incident is an extreme case study undertaken to examine its implications on the organisational legitimacy of British Petroleum (BP) and the latter’s response to the incident and beyond. The paper draws on Suchman’s legitimacy framework (1995) to understand sustainability governance as an organisational practice that evolved post the Gulf of Mexico oil spill to manage BP’s legitimacy. It draws on archival records and documentation from 2008 to 2017, as key sources for data collection, using interrogation by NVivo software.

Sustainability governance is a sound practice that was socially constructed to manage the re-legitimatisation process following the Gulf of Mexico oil spill. It is characterised by broadness (the interplay between the corporate governance and corporate social responsibility disciplines), dynamic (developing the tactics to repair and maintain legitimacy), agility (conforming to the accountability for socially responsible investment and ensuring steps towards geopolitically responsible investment) and interdependence (reflecting composition and interactions).

This paper has practical implications for organisations, in terms of sustainability governance’s constitution, mechanism and characteristics.

This paper has implications not only for organisations, in terms of sustainability governance’s characteristics, but also for policy-makers, regulators and accounting education. However, the present paper’s insights are achieved through an in-depth and longitudinal case study.

This paper has problematized the concept of sustainability governance and elaborated its evolution (the emergence, enactment, deployment and interplay) process. The sustainability governance showed an otherwise organisational response that moves our understanding of the deployment of disclosure for complex organisational change as a way to discredit events.

This study aims to investigate the dynamic interplay between the management control system (MCS) and organizational identity (OI) in the Deepwater Horizon incident involving British Petroleum (BP). It examines how the MCS manages challenges, particularly those addressing the embarrassment stemming from identity disparities between external portrayal (frontstage) and internal operations (backstage), with a focus on the often-underestimated influence of the media.

This study builds upon the frameworks developed by Ravasi and Schultz (2006) and Malmi and Brown (2008) to construct a theoretical framework that profoundly investigates the relationship between MCS and OI. The framework developed guided the research design and incorporated a qualitative approach complemented by an illustrative case study. The research data was rigorously gathered from diverse sources, including official BP documents and influential media outlets, with a particular focus on well-established American and British newspapers.

BP’s MCS plays a dual role: it exposes discrepancies in safety, leadership and values, causing embarrassment and identity damage, yet catalyses a sense-making process leading to organizational transformation and shifts in the OI. This transformation influences sense-giving and prompts changes in MCS. The study reveals an intricate interplay in identity management between frontstage audiences (e.g. influential media) and backstage actors (e.g. BP’s senior management). It highlights interdependencies both within and between MCS and OI, emphasizing their roles in interacting within identity management. The longitudinal recovery is intricately tied to mutual political interests between BP and the USA, which are significantly facilitated by the media’s role.

This study acknowledges limitations that point future research opportunities. Interviews could provide a more dynamic understanding of MCS changes and organizational transformations. Investigating the role of leadership, particularly the new chief executive office, and the influence of political versus organizational factors in shaping identity claims is essential. Additionally, the effectiveness and historical context of interdependencies should be quantitatively assessed. Theoretical limitations in the OI and MCS frameworks suggest the need for context-specific categorisations. This research serves as a foundation for further exploration of the intricate dynamics between MCS, OI and organizational responses to crises.

This study offers valuable insights with practical implications for organizations facing identity challenges in the wake of significant incidents. Organizations can better navigate crises by recognizing the multifaceted role of MCS in identity damage and restoration. It underscores the importance of addressing both frontstage and backstage aspects of OI while managing identity discrepancies, thereby enhancing transparency and credibility. Additionally, understanding the intricate interdependencies within OI and MCS can guide organizations in implementing more effective identity restoration strategies. Furthermore, the study highlights the significance of media influence and the need to engage with it strategically during crisis management.

This study’s findings have significant social implications for organizations and the broader public. By recognizing the multifaceted role of MCS in shaping identity, organizations can enhance transparency and credibility, rebuilding trust with the public. Additionally, the study highlights the critical role of media in influencing perceptions and decision-making during crises, emphasizing the importance of responsible and ethical reporting. Understanding the intricate interplay between MCS and OI can inform better crisis management strategies and improve how organizations respond to and recover from incidents, ultimately benefiting society by promoting more accountable and responsible corporate behaviour.

This study’s distinctness lies in its innovative exploration of MCS, which transcends traditional methodologies that focus narrowly on front or backstage aspects of OI and often adhere to predetermined MCS practices. It underscores the importance of concurrently addressing both the front- and backstage audiences in managing the embarrassment caused by identity discrepancies and restoration. The research uncovers multifaceted interdependencies within MCS and OI, and these extend beyond simplistic relationships and emphasize the complex nature of identity restoration management.

The purpose of this paper is to examine and report on the extent and firm characteristics that determine the practices of online financial disclosure (OFD) by the Islamic banks in the Gulf Cooperation Council (GCC) countries.

Data were collected using the websites of 48 Islamic banks listed on the stock markets in the GCC countries. Moreover, the study used the websites of the stock markets to get more financial information which was not found on the websites of the banks. The study covered a period of three years from 2015 to 2017. A checklist was used to compute the total level of OFD.

This study found that the overall level of OFD in the GCC by Islamic banks is 72.4 percent. The results also report a significant and positive relationship with firm size. On the other hand, the results show an insignificant relationship with profitability (ROE and ROA), leverage and age.

The paper provides awareness regarding OFD that might prove beneficial to the various stakeholders of the banks including investors, regulators and preparers of financial statements.

This paper is an important contribution to filling the gap in the literature, as there are a negligible number of studies dealing with OFD from an Islamic perspective.