S.S. Motsa and P. Sibanda
A detailed investigation of the effects of surface flexibility on the inviscid instability of boundary‐layer flow over a horizontal flat plate with heat transfer when the fluid…
Abstract
Purpose
A detailed investigation of the effects of surface flexibility on the inviscid instability of boundary‐layer flow over a horizontal flat plate with heat transfer when the fluid buoyancy is large is undertaken. The aim of this study is to determine whether the inviscid disturbances that arise at this limit are stabilized or destabilized by surface compliancy.
Design/methodology/approach
For large positive buoyancy numbers, the motion of the disturbances is governed by the Taylor‐Goldstein (TG) equation. Using the Chebyshev collocation spectral method, the eigen‐solutions of the TG equation are obtained and compared with known results from boundary‐layer flow over rigid flat plates.
Findings
The numerical results show that the effects of surface compliancy are important for small wave numbers and that for the inviscid modes, increasing surface parameters has the effect of destabilizing the flow. For large compliancy parameters the flow structure is indistinguishable from that which obtains in boundary layer flow over rigid surfaces.
Research limitations/implications
The multiplicity of the compliant wall parameters makes a full parametric study that should show the effect of varying the compliance of the boundary surface on the stability of the flow mathematically intractable. In this study only a brief parametric study, for selected parameters is presented.
Originality/value
It is believed that this paper would be of immense value to applied mathematicians and engineers working in the areas of boundary layer stability and natural convection flows. In the last four decades there has been overwhelming interest shown by researchers in convective boundary‐layer flow. This has largely stemmed from the numerous applications of such flows in geophysics and engineering problems. Many of these applications, for example, polymer and food processing involve the flow of a fluid over a flexible surface. This research aims to bring the dynamics of the surface as a possible mechanism to stabilize convective boundary layer flows and prevent separation.
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The purpose of this paper is to investigate the hydromagnetic steady flow and heat transfer characteristics of an incompressible viscous electrically conducting fluid past a…
Abstract
Purpose
The purpose of this paper is to investigate the hydromagnetic steady flow and heat transfer characteristics of an incompressible viscous electrically conducting fluid past a rotating disk in a porous medium with ohmic heating, Hall current and viscous dissipation are also investigated.
Design/methodology/approach
Using appropriate similarity variables and boundary‐layer approximations, the fluid equations for continuity, momentum and energy balance governing the problem are formulated. These equations are solved numerically by using the most effective Newton‐Raphson shooting method along with fourth‐order Runge‐Kutta integration algorithm.
Findings
It was found that magnetic field retards the fluid motion due to the opposing Lorentz force generated by the magnetic field. Both the magnetic field and the Eckert number tend to enhance the heat transfer efficiency. The Hall parameter however reduces the heat transfer rate. In terms of the friction coefficient, the magnetic interaction parameter, the Hall parameter and the Eckert number all combine to increase the skin friction, while increasing the Darcy number (increasing permeability) reduces the skin friction so increasing the fluid velocity.
Practical implications
This paper provides a very useful source of information for researchers on the subject of hydromagnetic flow in porous media.
Originality/value
This type of problem has potential to serve as a prototype for practical swirl problems, for example, axisymmetric flow in combustors.
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Mohamed Almakki, Hiranmoy Mondal and Precious Sibanda
This paper aims to investigate entropy generation in an incompressible magneto-micropolar nanofluid flow over a nonlinear stretching sheet. The flow is subjected to thermal…
Abstract
Purpose
This paper aims to investigate entropy generation in an incompressible magneto-micropolar nanofluid flow over a nonlinear stretching sheet. The flow is subjected to thermal radiation and viscous dissipation. The energy equation is extended by considering the impact of the Joule heating term because of an imposed magnetic field.
Design/methodology/approach
The flow, heat and mass transfer model are solved numerically using the spectral quasilinearization method. An analysis of the performance of this method is given.
Findings
It is found that the method is robust, converges fast and gives good accuracy. In terms of the physically significant results, the authors show that the irreversibility caused by the thermal diffusion the dominants other sources of entropy generation and the surface contributes significantly to the total irreversibility.
Originality/value
The flow is subjected to a combination of a buoyancy force, viscous dissipation, Joule heating and thermal radiation. The flow equations are solved numerically using the spectral quasiliearization method. The impact of a range of physical and chemical parameters on entropy generation, velocity, angular velocity, temperature and concentration profiles are determined. The current results may help in industrial applicants. The present problem has not been considered elsewhere.
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Mangwiro Magodora, Hiranmoy Mondal and Precious Sibanda
The purpose of this paper is to focus on the application of Chebyshev spectral collocation methodology with Gauss Lobatto grid points to micropolar fluid over a stretching or…
Abstract
Purpose
The purpose of this paper is to focus on the application of Chebyshev spectral collocation methodology with Gauss Lobatto grid points to micropolar fluid over a stretching or shrinking surface. Radiation, thermophoresis and nanoparticle Brownian motion are considered. The results have attainable scientific and technological applications in systems involving stretchable materials.
Design/methodology/approach
The model equations governing the flow are transformed into non-linear ordinary differential equations which are then reworked into linear form using the Newton-based quasilinearization method (SQLM). Spectral collocation is then used to solve the resulting linearised system of equations.
Findings
The validity of the model is established using error analysis. The velocity, temperature, micro-rotation, skin friction and couple stress parameters are conferred diagrammatically and analysed in detail.
Originality/value
The study obtains numerical explanations for rapidly convergent solutions using the spectral quasilinearization method. Convergence of the numerical solutions was monitored using the residual error analysis. The influence of radiation, heat and mass parameters on the flow are depicted graphically and analysed. The study is an extension on the work by Zheng et al. (2012) and therefore the novelty is that the authors tend to take into account nanoparticles, Brownian motion and thermophoresis in the flow of a micropolar fluid.
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Subrata Das, Hiranmoy Mondal, Prabir Kumar Kundu and Precious Sibanda
The focus of the paper is only on the contributions toward the use of entropy generation of non-Newtonian Casson fluid over an exponential stretching sheet. The purpose of this…
Abstract
Purpose
The focus of the paper is only on the contributions toward the use of entropy generation of non-Newtonian Casson fluid over an exponential stretching sheet. The purpose of this paper is to investigate the entropy generation and homogeneous–heterogeneous reaction. Velocity and thermal slips are considered instead of no-slip conditions at the boundary.
Design/methodology/approach
Basic equations in form of partial differential equations are converted into a system of ordinary differential equations and then solved using the spectral quasi-linearization method (SQLM).
Findings
The validity of the model is established using error analysis. Variation of the velocity, temperature, concentration profiles and entropy generation against some of the governing parameters are presented graphically. It is to be noted that the increase in entropy generation due to increase in heterogeneous reaction parameter is due to the increase in heat transfer irreversibility. It is further noted that the Bejan number decreases with Brinkman number because increase in Brinkman number reduces the total entropy generation.
Originality/value
This paper acquires realistic numerical explanations for rapidly convergent temperature and concentration profiles using the SQLM. Convergence of the numerical solutions was monitored using the residual error of the PDEs. The resulting equations are then integrated using the SQLM. The influence of emergent flow, heat and mass transfer parameters effects are shown graphically.
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Thanh Tiep Le and Sukalpa Chakrabarti
The aim of this study is to provide a further understanding of how and when social media (SM) boosts firm performance (FP) by exploring the mediation role of business innovation…
Abstract
Purpose
The aim of this study is to provide a further understanding of how and when social media (SM) boosts firm performance (FP) by exploring the mediation role of business innovation capabilities (BI) and firm competitiveness (FC) in the link between SM and FP.
Design/methodology/approach
This study uses a quantitative approach using small and medium sized enterprises (SMEs) in emerging market as an empirical field of research. The population of this study is the management level of SMEs and professionals. This study surveyed 425 samples to get primary data for quantitative analysis. This study uses Smart PLS SEM version 3.3.2 to analyze the collected data.
Findings
This study found that SM directly and indirectly affects FP through BI and FC. Besides, BI and FC mediated the relationship between SM and FP.
Originality/value
The originality of this study lies in the operationalization of an unexplored integrated framework using SMEs in emerging market as an empirical field of research from the perspective of combination of diffusion of innovations theory and resource advantage theory. This study thus provides a new approach to the potential of SM for business innovation capabilities oriented toward sustainability. Drawing on the findings of this study, theoretical and managerial implications are proposed which may be of great interests to business practitioners, business owners, business directors and managers to operate their organizations efficiently through making optimal use of SM platforms.
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Mingyue Fan, Yue Tang, Sikandar Ali Qalati and Blend Ibrahim
This investigation endeavors to examine the routes by which environmental–social–governance (ESG) performance influences the competitive landscape for logistics enterprises, with…
Abstract
Purpose
This investigation endeavors to examine the routes by which environmental–social–governance (ESG) performance influences the competitive landscape for logistics enterprises, with a particular emphasis on the function of digitalization in this complex process. The research underscores the significance of the ESG context in the realm of digitalization, providing valuable insights into its impact on the overall competitiveness of logistics enterprises.
Design/methodology/approach
This research gathers information from a total of 90 logistics enterprises that are publicly traded on the Shanghai and Shenzhen A-share stock markets for analysis and model testing. Due to the multiple pathways of influence and the constrained size of the sample, it has been decided that the Piecewise structural–equation–modeling (SEM) approach will be employed.
Findings
The research reveals that ESG factors positively impact enterprises' competitiveness (EC). The augmentation of competitiveness is attributed to the moderating role of green technology innovation (GTI) and agency costs between ESG and EC. In the context of digitalization, the level of digitalization of logistics enterprises may create a capital squeeze effect on environmental performance, weakening competitiveness. Conversely, the level of digitalization positively regulates the promoting effect of governance performance on competitiveness.
Originality/value
This research provides a sound theoretical foundation for understanding how ESG contributes to boosting the competitiveness of Chinese logistics enterprises and extends the application of Piecewise SEM in the research field of logistics enterprise competitiveness. Furthermore, it offers a practical pathway for companies to implement ESG practices and foster competitiveness in digital environments.
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Sanjay Kumar and Kushal Sharma
The present study aims to investigate the effect of radiation on the unsteady magnetohydrodynamic (MHD) flow of a viscous, electrically conducting Newtonian fluid over rotating…
Abstract
Purpose
The present study aims to investigate the effect of radiation on the unsteady magnetohydrodynamic (MHD) flow of a viscous, electrically conducting Newtonian fluid over rotating disk moving upward/downward immersed in a porous medium, considering the Hall effect. The study is motivated by the various applications in the context of solar power technology, electric power generation, Hall accelerators, MHDs generators and other industrial areas when the fluid flow is subjected to the previously mentioned effects such as MHD, Hall effect and thermal radiation.
Design/methodology/approach
Suitable similarity transformations are employed to reduce the governing nonlinear partial differential equations into the nonlinear ordinary ones. The solutions of the reduced system are numerically obtained using the boundary value problem (BVP) Midrich scheme in Maple. The results are presented graphically for vertical disk movement, magnetic parameter, Hall current, Darcy parameter, thermal radiation and Schmidt number. Skin frictions, mass and heat transfer rates are numerically tabulated.
Findings
It is revealed that the vertical motion of the disk significantly boosts the radial and annular flows. Moreover, the Hall parameter has contrasting effects on velocity profiles for the range of magnetic field but temperature field is oblivious of this behavior. It is observed that heat and mass transfer considerably enhance along vertical disk movement. Also magnetic field, temperature ratio and radiation parameter significantly enhance the temperature field, while reaction rate parameter and Schmidt number decrease the concentration profile. The current model is calibrated in its reduced form to an already published literature with good correlation to ensure the numerical scheme's validity.
Originality/value
This work is original within the best efforts of the authors.
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Nesrine Sassi and Salma Damak-Ayadi
The purpose of this study is to examine the indirect relationship between the mandatory adoption of International Financial Reporting Standards for small and medium-sized…
Abstract
Purpose
The purpose of this study is to examine the indirect relationship between the mandatory adoption of International Financial Reporting Standards for small and medium-sized enterprises (IFRS for SMEs) and the corporate governance index (CGI) by checking the mediating effect of the quality of financial statements (QFS) on this relationship.
Design/methodology/approach
The main objective of the IFRS for SMEs standard is to meet the specific needs of SMEs in transition and developing economies. Here, the authors used the structural equation method to investigate SMEs in countries that mandate the application of IFRS for SMEs for the years 2010 (pre-adoption) and 2016 (post-adoption). The final sample covered two emerging countries: the Dominican Republic and El Salvador.
Findings
The results show a positive association between the adoption of IFRS for SMEs, CGI and QFS. Furthermore, the findings confirm that the relationship between IFRS for SMEs adoption and CGI is under the control of the QFS.
Originality/value
This study provides standard setters and managers of SMEs with an overview of the importance of QFS on the significance of this relationship in emerging countries. The study contributes to the literature by examining the indirect relationship between IFRS for SMEs and CGI and building a CGI that integrates a set of governance practices linked to SMEs.
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Salma Damak-Ayadi, Nesrine Sassi and Moujib Bahri
The purpose of this study is to identify the influence of environmental and institutional factors on the adoption of the International Financial Reporting Standard for small and…
Abstract
Purpose
The purpose of this study is to identify the influence of environmental and institutional factors on the adoption of the International Financial Reporting Standard for small and medium-sized entities (IFRS for SMEs). This study used the neo-institutional theory and the economic theory of networks to explain why countries choose to adopt IFRS for SMEs.
Design/methodology/approach
This study is based on logistic regression analysis to investigate 177 countries, including 77 jurisdictions that adopted IFRS for SMEs between 2009 and 2015.
Findings
The findings confirm that the adoption of IFRS for SMEs is significantly related to law enforcement quality, culture, trading networks and economic growth. At the institutional level, coercive and normative isomorphism was found to be positively associated with IFRS for SMEs adoption. The results show also that the quality of the audit has no significant effect on the adoption of IFRS for SMEs. However, the joint effect of the quality of audit and quality of law enforcement is significantly related to the adoption of IFRS for SMEs.
Practical implications
The study contributes to a better understanding of the factors influencing the implementation of IFRS for SMEs standard across the globe and could be used to predict a country’s decision to adopt this standard.
Originality/value
This study contributes to the literature on international accounting harmonization by examining both environmental and institutional factors that influence the adoption of IFRS for unlisted private companies.