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Article
Publication date: 12 July 2024

Abdulaziz Alsenafi, Fares Alazemi and M. Nawaz

To improve the thermal performance of base fluid, nanoparticles of three types are dispersed in the base fluid. A novel theory of non-Fourier heat transfer is used for design and…

Abstract

Purpose

To improve the thermal performance of base fluid, nanoparticles of three types are dispersed in the base fluid. A novel theory of non-Fourier heat transfer is used for design and development of models. The thermal performance of sample fluids is compared to determine which types of combination of nanoparticles are the best for an optimized enhancement in thermal performance of fluids. This article aims to: (i) investigate the impact of nanoparticles on thermal performance; and (ii) implement the Galerkin finite element method (GFEM) to thermal problems.

Design/methodology/approach

The mathematical models are developed using novel non-Fourier heat flux theory, conservation laws of computational fluid dynamics (CFD) and no-slip thermal boundary conditions. The models are approximated using thermal boundary layer approximations, and transformed models are solved numerically using GFEM. A grid-sensitivity test is performed. The accuracy, correction and stability of solutions is ensured. The numerical method adopted for the calculations is validated with published data. Quantities of engineering interest, i.e. wall shear stress, wall mass flow rate and wall heat flux, are calculated and examined versus emerging rheological parameters and thermal relaxation time.

Findings

The thermal relaxation time measures the ability of a fluid to restore its original thermal state, called thermal equilibrium and therefore, simulations have shown that the thermal relaxation time associated with a mono nanofluid has the most substantial effect on the temperature of fluid, whereas a ternary nanofluid has the smallest thermal relaxation time. A ternary nanofluid has a wider thermal boundary thickness in comparison with base and di- and mono nanofluids. The wall heat flux (in the case of the ternary nanofluids) has the most significant value compared with the wall shear stresses for the mono and hybrid nanofluids. The wall heat and mass fluxes have the highest values for the case of non-Fourier heat and mass diffusion compared to the case of Fourier heat and mass transfer.

Originality/value

An extensive literature review reveals that no study has considered thermal and concentration memory effects on transport mechanisms in fluids of cross-rheological liquid using novel theory of heat and mass [presented by Cattaneo (Cattaneo, 1958) and Christov (Christov, 2009)] so far. Moreover, the finite element method for coupled and nonlinear CFD problems has not been implemented so far. To the best of the authors’ knowledge for the first time, the dynamics of wall heat flow rate and mass flow rate under simultaneous effects of thermal and solute relaxation times, Ohmic dissipation and first-order chemical reactions are studied.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 34 no. 9
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 27 August 2024

Umar Farooq, Tao Liu, Ahmed Jan, Umer Farooq and Samina Majeed

In this study, we investigate the effects of an extended ternary hybrid Tiwari and Das nanofluid model on ethylene glycol flow, with a focus on heat transfer. Using the Cross…

Abstract

Purpose

In this study, we investigate the effects of an extended ternary hybrid Tiwari and Das nanofluid model on ethylene glycol flow, with a focus on heat transfer. Using the Cross non-Newtonian fluid model, we explore the heat transfer characteristics of this unique fluid in various applications such as pharmaceutical solvents, vaccine preservatives, and medical imaging techniques.

Design/methodology/approach

Our investigation reveals that the flow of this ternary hybrid nanofluid follows a laminar Cross model flow pattern, influenced by heat radiation and occurring around a stretched cylinder in a porous medium. We apply a non-similarity transformation to the nonlinear partial differential equations, converting them into non-dimensional PDEs. These equations are subsequently solved as ordinary differential equations (ODEs) using MATLAB’s bvp4c tools. In addition, the magnetic number in this study spans from 0 to 5, volume fraction of nanoparticles varies from 5% to 10%, and Prandtl number for EG as 204. This approach allows us to examine the impact of temperature on heat transfer and distribution within the fluid.

Findings

Graphical depictions illustrate the effects of parameters such as the Weissenberg number, porous parameter, Schmidt number, thermal conductivity parameter, Soret number, magnetic parameter, Eckert number, Lewis number, and Peclet number on velocity, temperature, concentration, and microorganism profiles. Our results highlight the significant influence of thermal radiation and ohmic heating on heat transmission, particularly in relation to magnetic and Darcy parameters. A higher Lewis number corresponds to faster heat diffusion compared to mass diffusion, while increases in the Soret number are associated with higher concentration profiles. Additionally, rapid temperature dissipation inhibits microbial development, reducing the microbial profile.

Originality/value

The numerical analysis of skin friction coefficients and Nusselt numbers in tabular form further validates our approach. Overall, our findings demonstrate the effectiveness of our numerical technique in providing a comprehensive understanding of flow and heat transfer processes in ternary hybrid nanofluids, offering valuable insights for various practical applications.

Details

Multidiscipline Modeling in Materials and Structures, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 3 September 2024

J. Jayaprakash, Vediyappan Govindan, S.S. Santra, S.S. Askar, Abdelaziz Foul, Susmay Nandi and Syed Modassir Hussain

Scientists have been conducting trials to find ways to reduce fuel consumption and enhance heat transfer rates to make heating systems more efficient and cheaper. Adding solid…

Abstract

Purpose

Scientists have been conducting trials to find ways to reduce fuel consumption and enhance heat transfer rates to make heating systems more efficient and cheaper. Adding solid nanoparticles to conventional liquids may greatly improve their thermal conductivity, according to the available evidence. This study aims to examine the influence of external magnetic flux on the flow of a mixed convective Maxwell hybrid non-Newtonian nanofluid over a linearly extending porous flat plate. The investigation considers the effects of thermal radiation, Dufour and Soret.

Design/methodology/approach

The mathematical model is formulated based on the fundamental assumptions of mass, energy and momentum conservation. The implicit models are epitomized by a set of interconnected nonlinear partial differential equations, which include a suitable and comparable adjustment. The numerical solution to these equations is assessed for approximate convergence by the Runge−Kutta−Fehlberg method based on the shooting technique embedded with the MATLAB software.

Findings

The findings are presented through graphical representations, offering a visual exploration of the effects of various dynamic parameters on the flow field. These parameters encompass a wide range of factors, including radiation, thermal and Brownian diffusion parameters, Eckert, Lewis and Soret numbers, magnetic parameters, Maxwell fluid parameters, Darcy numbers, thermal and solutal buoyancy factors, Dufour and Prandtl numbers. Notably, the authors observed that nanoparticles with a spherical shape exerted a significant influence on the stream function, highlighting the importance of nanoparticle geometry in fluid dynamics. Furthermore, the analysis revealed that temperature profiles of nanomaterials were notably affected by their shape factor, while concentration profiles exhibited an opposite trend, providing valuable insights into the behavior of nanofluids in porous media.

Originality/value

A distinctive aspect of the research lies in its novel exploration of the impact of external magnetic flux on the flow of a mixed convective Maxwell hybrid non-Newtonian nanofluid over a linearly extending porous flat plate. By considering variables such as solar radiation, external magnetic flux, thermal and Brownian diffusion parameters and nanoparticle shape factor, the authors ventured into uncharted territory within the realm of fluid dynamics. These variables, despite their significant relevance, have not been extensively studied in previous research, thus underscoring the originality and value of the authors’ contribution to the field.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 16 July 2024

Fehid Ishtiaq, R. Ellahi, M.M. Bhatti and Sadiq M. Sait

Cilia serves numerous biological functions in the human body. Malfunctioning of nonmotile or motile cilia will have different kinds of consequences for human health. More…

Abstract

Purpose

Cilia serves numerous biological functions in the human body. Malfunctioning of nonmotile or motile cilia will have different kinds of consequences for human health. More specifically, the directed and rhythmic beat of motile cilia facilitates the unidirectional flow of fluids that are crucial in both homeostasis and the development of ciliated tissues. In cilia-dependent hydrodynamic flows, tapering geometries look a lot like the structure of biological pathways and vessels, like airways and lymphatic vessels. In this paper, the Carreau fluid model through the cilia-assisted tapered channel (asymmetric) under the influence of induced magnetic field and convective heat transfer is investigated.

Design/methodology/approach

Lubrication theory is a key player in the mathematical formulation of momentum, magnetic field and energy equations. The formulated nonlinear and coupled differential equations are solved with the aid of the homotopy perturbation method (HPM). The graphical results are illustrated with the help of the computational software “Mathematica.”

Findings

The impact of diverse emerging physical parameters on velocity, induced magnetic field, pressure rise, current density and temperature profiles is presented graphically. It is observed that the cilia length parameter supported the velocity and current density profiles, while the Hartman number and Weissenberg number were opposed. A promising effect of emerging parameters on streamlines is also perceived.

Originality/value

The study provides novel aspects of cilia-driven induced magnetohydrodynamics flow of Carreau fluid under the influence of induced magnetic field and convective heat transfer through the asymmetric tapered channel.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 34 no. 9
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 17 September 2024

Khurram Shahzad, Shakeel Ahmad Khan, Asfa Muhammed Din Javeed, Mujahid Latif and Omar Shabbir

The purpose of this study is to conduct a bibliometric analysis to discover the published information on the effects of e-learning technologies on innovative competency…

Abstract

Purpose

The purpose of this study is to conduct a bibliometric analysis to discover the published information on the effects of e-learning technologies on innovative competency development of university librarians and smart library services.

Design/methodology/approach

This study is based on bibliometric research methodology. The data were retrieved from the leading database Web of Science to analyze the scholarly publications on the topic during 1965–2023. VOSviewer and Biblioshiny software were used to analyze the bibliometric data on the subject.

Findings

Results displayed that the topic of e-learning technologies in the domain of librarianship has been greatly used by several authors as a title to publish their research work. The dominance of countries such as the USA, China and the UK in research output reveals their leadership in advancing research and innovation in the field of e-learning technologies for university libraries.

Originality/value

To the best of the authors’ knowledge, this is the first bibliometric study that has been conducted to measure the productivity of literature at the international level on the effects of e-learning technologies on innovative competency development of university librarians and smart library services.

Details

Global Knowledge, Memory and Communication, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2514-9342

Keywords

Article
Publication date: 29 August 2024

Sanjai K.K. Parahoo, Sabiha Mumtaz, Ebrahim Soltani and Latifa Alnuaimi

Leveraging the job demands-resources (JD-R) theory, this study proposes and validates a mediation model depicting the impact of health-promoting leadership (HPL) on innovation…

Abstract

Purpose

Leveraging the job demands-resources (JD-R) theory, this study proposes and validates a mediation model depicting the impact of health-promoting leadership (HPL) on innovation performance (IP), with the relationship partially mediated by two health-related factors: psychological well-being (PWB) and positive conflict (PC).

Design/methodology/approach

Employing a structured questionnaire developed from validated scales sourced from the existing literature, the study collected data from a sample of 310 employees across various organizations within the service sector of the United Arab Emirates. The dimensionality, reliability, and validity of scales were assessed using exploratory and confirmatory factor analysis. The study’s seven hypotheses were tested through structural equation modeling in AMOS and mediation analysis using the Hayes process model in SPSS.

Findings

Support was found for all seven hypotheses, demonstrating that HPL exerts both a direct and an indirect effect on IP, with PWB and PC serving as partial mediators.

Research limitations/implications

Distinct from the traditional leadership literature, which often views an employee’s psychological health as a personal matter, this study highlights the organizational role in promoting psychological well-being. It also provides significant theoretical contributions to the underexplored area of conflict management within the context of innovation.

Practical implications

By promoting employees' PWB, HPL can optimize human capital within organizations. Additionally, leaders can leverage the potential of PC to foster an environment conducive to innovation, resulting in enhanced organizational performance.

Originality/value

The findings enrich the leadership and IP literature by identifying inter-relationships between the three health related antecedents of IP.

Details

International Journal of Productivity and Performance Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1741-0401

Keywords

Article
Publication date: 7 February 2024

Moh’d Anwer AL-Shboul

This study attempts to explore the linkages between reliable big and cloud data analytics capabilities (RB&CDACs) and the comparative advantage (CA) that applies in the…

Abstract

Purpose

This study attempts to explore the linkages between reliable big and cloud data analytics capabilities (RB&CDACs) and the comparative advantage (CA) that applies in the manufacturing sector in the countries located in North Africa (NA). These are considered developing countries through generating green product innovation (GPI) and using green process innovations (GPrLs) in their processes and functions as mediating factors, as well as the moderating role of data-driven competitive sustainability (DDCS).

Design/methodology/approach

To achieve the aim of this study, 346 useable surveys out of 1,601 were analyzed, and valid responses were retrieved for analysis, representing a 21.6% response rate by applying the quantitative methodology for collecting primary data. Convergent validity and discriminant validity tests were applied to structural equation modeling (SEM) in the CB-covariance-based structural equation modeling (SEM) program, and the data reliability was confirmed. Additionally, a multivariate analysis technique was used via CB-SEM, as hypothesized relationships were evaluated through confirmatory factor analysis (CFA), and then the hypotheses were tested through a structural model. Further, a bootstrapping technique was used to analyze the data. We included GPI and GPrI as mediating factors, while using DDCS as a moderated factor.

Findings

The empirical findings indicated that the proposed moderated-mediation model was accepted due to the relationships between the constructs being statistically significant. Further, the findings showed that there is a significant positive effect in the relationship between reliable BCDA capabilities and CAs as well as a mediating effect of GPI and GPrI, which is supported by the proposed formulated hypothesis. Additionally, the findings confirmed that there is a moderating effect represented by data-driven competitive advantage suitability between GPI, GPrI and CA.

Research limitations/implications

One of the main limitations of this study is that an applied cross-sectional study provides a snapshot at a given moment in time. Furthermore, it used only one type of methodological approach (i.e. quantitative) rather than using mixed methods to reach more accurate data.

Originality/value

This study developed a theoretical model that is obtained from reliable BCDA capabilities, CA, DDCS, green innovation and GPrI. Thus, this piece of work bridges the existing research gap in the literature by testing the moderated-mediation model with a focus on the manufacturing sector that benefits from big data analytics capabilities to improve levels of GPI and competitive advantage. Finally, this study is considered a road map and gaudiness for the importance of applying these factors, which offers new valuable information and findings for managers, practitioners and decision-makers in the manufacturing sector in the NA region.

Book part
Publication date: 4 September 2024

Narayanage Jayantha Dewasiri, Mawarala Vitharanage Probodika Hanshani, Mananage Shanika Hansini Rathnasiri and Simon Grima

Purpose: This chapter examines the effect of green banking practices (GBPs) on environmental performance (EP), specifically focussing on the Sri Lankan banking industry…

Abstract

Purpose: This chapter examines the effect of green banking practices (GBPs) on environmental performance (EP), specifically focussing on the Sri Lankan banking industry. Additionally, the study explores the mediating impact of green finance in the association between GBPs and the EP of banks listed in the Colombo Stock Exchange in Sri Lanka.

Methodology: The survey included 233 banking employees from Sri Lanka, and data for this study were collected via questionnaires. The formulated hypotheses were tested employing a regression analysis.

Findings: GBPs such as employee, customer, operation, and policy-related practices significantly predicted the banks’ EP. Furthermore, the study highlights that green finance partially mediates the relationship between GBPs and banks’ EP in Sri Lanka.

Implications of the study: The study’s results indicate that banks should prioritise integrating GBPs in their organisations to enhance environmental and overall performance. Moreover, strategically utilising green financing techniques might be a substantial channel for banks to further strengthen their ecological dedication and influence.

Originality: This is the first study to investigate the impact of GBPs on banks’ EP with the mediating effect of green finance in the Sri Lankan context.

Article
Publication date: 20 September 2024

Aamer Shahzad, Mian Sajid Nazir, Flávio Morais and Affaf Asghar Butt

The role played by corporate governance mechanisms on corporate deleveraging policies has not been clarified. Empirical evidence is confined to developed economies, even with…

Abstract

Purpose

The role played by corporate governance mechanisms on corporate deleveraging policies has not been clarified. Empirical evidence is confined to developed economies, even with conflicting and inconclusive results. This paper aims to examine the role of corporate governance mechanisms, such as ownership structure, board composition and CEO dominance, in explaining corporate deleveraging policies.

Design/methodology/approach

Using a sample of listed Pakistani firms between 2010 and 2022, this study resorts to binary response models to examine the effects of governance mechanisms on firms’ decision to go debt-free.

Findings

A greater ownership concentration, institutional ownership and family ownership increase the propensity for zero leverage. Board gender diversity decreases the propensity for deleveraging policies, which seems to indicate that the presence of females reinforces the monitoring function of the board. Finally, lower managerial ownership or CEO dominance decreases the propensity toward zero leverage (interest convergence hypothesis), but higher managerial ownership or CEO dominance increases the propensity toward zero leverage (managerial entrenchment hypothesis).

Practical implications

Risk-averse managers who prefer to control a firm using little or no debt will find it easier to implement these financing policies in firms with greater ownership concentration and where institutional holders have a substantial stake. For shareholders, this study suggests that investing in firms with females on board reduces the risk of corporate deleveraging policies being adopted for entrenched reasons.

Social implications

The presence of females on board seems to decrease the propensity of managers to adopt opportunistic actions and may also contribute to enhancing human welfare and society in developing countries.

Originality/value

To the best of the authors’ knowledge, this is the first study considering the effect of board diversity on zero leverage. Another singularity is that this study exhibits a nonlinear relationship between managerial ownership and corporate deleveraging policy.

Details

Corporate Governance: The International Journal of Business in Society, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1472-0701

Keywords

Open Access
Article
Publication date: 4 July 2024

Shinta Amalina Hazrati Havidz, Maria Divina Santoso, Theodore Alexander and Caroline Caroline

This study aims to identify the financial attributes of non-fungible tokens (NFTs) as safe havens, hedges or diversifiers against traditional (stock indices, foreign exchange…

Abstract

Purpose

This study aims to identify the financial attributes of non-fungible tokens (NFTs) as safe havens, hedges or diversifiers against traditional (stock indices, foreign exchange, gold and government bonds) and digital (Bitcoin and Ethereum) assets.

Design/methodology/approach

The quantile via moments was utilized, and the data spanned from 20 September 2021 to 31 January 2022. The authors incorporated feasible generalized least squares (FGLS) and difference-generalized method of moments (diff-GMM) as the robustness check.

Findings

Overall, NFTs offer strongly safe havens, hedging and diversifier attributes against cryptocurrencies, while weak properties for traditional assets. The specific findings are: (1) Bored Ape Yacht Club (BAYC) serves as a strong hedge for Bitcoin during market rise; (2) Mutant Ape Yacht Club (MAYC) serves as a strong safe haven against Bitcoin during market bull; (3) Crypto punk (CP) provides strong safe havens properties for gold during market turmoil while serving as a strong hedge against gold and Bitcoin on average and (4) the three blue-chip NFTs are powered by Ethereum blockchain, thus serving as a diversifier against Ethereum.

Practical implications

Bitcoin investors are suggested to include NFTs in their investment portfolio to mitigate the losses when Bitcoin falls. Meanwhile, the inclusion of crypto punk is advised for risk-averse investors who invest in gold. NFTs are powered by the Ethereum blockchain, indicating co-movement among them and thus, serve as diversifiers. Policymakers and regulators are suggested to watch closely over NFTs' great development and restructure the existing policies and thus, stabilization of asset markets can be achieved.

Originality/value

The originality aspects are: (1) focusing on the three blue-chip NFTs (i.e. BAYC, MAYC and CP) that are categorized as the largest NFTs by floor market capitalization; (2) testing the NFT attributes (safe havens, hedges or diversifiers) against traditional and digital assets, a.k.a., cryptocurrencies and (3) panel setting on 14 countries with the highest NFT users.

Details

Asian Journal of Accounting Research, vol. 9 no. 4
Type: Research Article
ISSN: 2459-9700

Keywords

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