Md. Jashim Uddin, O. Anwar Bég and Izani Md. Ismail
The purpose of this paper is to study two-dimensional nonlinear radiative-convective, steady-state boundary layer flow of non-Newtonian power-law nanofluids along a flat vertical…
Abstract
Purpose
The purpose of this paper is to study two-dimensional nonlinear radiative-convective, steady-state boundary layer flow of non-Newtonian power-law nanofluids along a flat vertical plate in a saturated porous medium taking into account thermal and mass convective boundary conditions numerically.
Design/methodology/approach
The governing equations are reduced to a set of coupled nonlinear ordinary differential equations with relevant boundary conditions. The transformed equations are then solved using the Runge-Kutta-Fehlberg fourth-fifth order numerical method with Maple 17 and Adomian decomposition method (ADM) in Mathematica.
Findings
The transformed equations are controlled by the parameter: power-law exponent, n; temperature ratio, Tr; Rosseland radiation-conduction, R; conduction-convection, Nc; and diffusion-convection, Nd. Temperature and nanoparticle concentration is enhanced with convection-diffusion parameter as are temperatures. Velocities are depressed with greater power-law rheological index whereas temperatures are elevated. Increasing thermal radiation flux accelerate the flow but to strongly heat the boundary layer. Very good correlation of the Maple solutions with previous stationary free stream and ADM solutions for a moving free stream, are obtained.
Practical implications
The study is relevant to high temperature nano-polymer manufacturing systems.
Originality/value
Lie symmetry group is used for the first time to transform the governing equations into a set of coupled nonlinear ordinary differential equations with relevant boundary conditions. The study is relevant to high temperature nano-polymer manufacturing systems.
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E.N. Maraj, Noreen Sher Akbar, Nabeela Kousar, Iffat Zehra and Taseer Muhammad
This paper aims to study the fluid flow and heat transfer within the Casson nanofluid confined between disk and cone both rotating with distinct velocities. For a comprehensive…
Abstract
Purpose
This paper aims to study the fluid flow and heat transfer within the Casson nanofluid confined between disk and cone both rotating with distinct velocities. For a comprehensive investigation, two distinct nano-size particles, namely, silicon dioxide and silicon carbide, are submerged in ethanol taken as the base fluid.
Design/methodology/approach
This paper explores the disk and cone contraption mostly encountered for viscosity measurement in various industrial applications such as lubrication industry, hydraulic brakes, pharmaceutical industry, petroleum and gas industry and chemical industry.
Findings
It is worth mentioning here that the radially varying temperature profile at the disk surface is taken into the account. The effect of prominent emerging parameters on velocity fields and temperature distribution are studied graphically, while bar graphs are drawn to examine the physical quantities of industrial interest such as surface drag force and heat transfer rate at disk and cone.
Originality/value
To the best of the authors’ knowledge, no study in literature exists that discusses the thermal enhancement of nano-fluidic transport confined between disk and cone both rotating with distinct angular velocities with heat transfer.
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Auwalu Musa, Rohaida Abdul Latif and Jamaliah Abdul Majid
This study examines whether the risk management committee (RMC) mitigates earnings management (EM) in Nigeria.
Abstract
Purpose
This study examines whether the risk management committee (RMC) mitigates earnings management (EM) in Nigeria.
Design/methodology/approach
The study used a sample of 365 firm-year observations of Nigerian-listed nonfinancial companies from 2018 to 2022. Driscoll and Kraay’s fixed-effect standard error regression model is used to test the hypotheses.
Findings
The study finds that RMC size, expertise, meeting frequency and membership overlapping with the audit committee have a negative effect on both accrual earnings management (AEM) and real earnings management (REM). While RMC independence is found to have a negative effect on REM. Moreover, additional tests reveal that RMC effectiveness is significantly associated with lower EM practices. Further analysis using the industry level finds that RMC attributes mitigate EM practices in some industries. The results remain after rigorous, robust analysis for endogeneity and alternative regressions.
Research limitations/implications
This study is limited to a sample of Nigerian-listed nonfinancial service companies for a period of five years, resulting in the non-generalizability of the findings to different contexts as the countries’ internal policies and regulations varied.
Practical implications
The findings have important implications for regulators, policymakers and investors that a stand-alone RMC can effectively help to evaluate potential risk activities and implement a proper risk management system, thereby mitigating EM practices. The result can help investors, analysts and other stakeholders across the international community in considering RMC information to evaluate potential risk and earnings management practices.
Originality/value
Following the NCCG 2018 reform in Nigeria that requires listed firms to create a standalone RMC, this study is among the earliest that examines the effect of RMC attributes on EM practices and emerging markets. As such, the findings may draw the attention of regulators and policymakers across the African market and the international community to the monitoring role of RMC attributes in mitigating EM practices.
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Health plays a crucial role in the daily lives and supporting health is the important role of medicine. With the availability of traditional, complementary and alternative…
Abstract
Purpose
Health plays a crucial role in the daily lives and supporting health is the important role of medicine. With the availability of traditional, complementary and alternative medicine (TCAM), the demands and willingness to pay among users are increasing. Hence, this study aims to determine the psychological factors influencing the willingness to pay for TCAM among Malaysian adults.
Design/methodology/approach
In total, 300 completed self-administered questionnaires were collected from Malaysian adults using a purposive sampling method through intercepts at public health-care facilities. A structural equation modelling approach using partial least square was used to test the hypotheses.
Findings
The findings show that attitude, subjective norms, perceived price and knowledge have a significant impact on willingness to pay for TCAM. Surprisingly, there was no relationship found between perceived behavioural control and health consciousness on willingness to pay for TCAM.
Originality/value
The findings of this study are expected to provide better insights into TCAM use among Malaysian adults. The results are also important to encourage health-care institutions and practitioners to educate the general public on the safety of TCAM to ensure more health benefits to the users.
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Noreen Sher Akbar, O. Anwar Beg and Z.H. Khan
Sheet processing of magnetic nanomaterials is emerging as a new branch of smart materials’ manufacturing. The efficient production of such materials combines many physical…
Abstract
Purpose
Sheet processing of magnetic nanomaterials is emerging as a new branch of smart materials’ manufacturing. The efficient production of such materials combines many physical phenomena including magnetohydrodynamics (MHD), nanoscale, thermal and mass diffusion effects. To improve the understanding of complex inter-disciplinary transport phenomena in such systems, mathematical models provide a robust approach. Motivated by this, this study aims to develop a mathematical model for steady, laminar, MHD, incompressible nanofluid flow, heat and mass transfer from a stretching sheet.
Design/methodology/approach
This study developed a mathematical model for steady, laminar, MHD, incompressible nanofluid flow, heat and mass transfer from a stretching sheet. A uniform constant-strength magnetic field is applied transversely to the stretching flow plane. The Buongiorno nanofluid model is used to represent thermophoretic and Brownian motion effects. A non-Fourier (Cattaneo–Christov) model is used to simulate thermal conduction effects, of which the Fourier model is a special case when thermal relaxation effects are neglected.
Findings
The governing conservation equations are rendered dimensionless with suitable scaling transformations. The emerging nonlinear boundary value problem is solved with a fourth-order Runge–Kutta algorithm and also shooting quadrature. Validation is achieved with earlier non-magnetic and forced convection flow studies. The influence of key thermophysical parameters, e.g. Hartmann magnetic number, thermal Grashof number, thermal relaxation time parameter, Schmidt number, thermophoresis parameter, Prandtl number and Brownian motion number on velocity, skin friction, temperature, Nusselt number, Sherwood number and nanoparticle concentration distributions, is investigated.
Originality/value
A strong elevation in temperature accompanies an increase in Brownian motion parameter, whereas increasing magnetic parameter is found to reduce heat transfer rate at the wall (Nusselt number). Nanoparticle volume fraction is observed to be strongly suppressed with greater thermal Grashof number, Schmidt number and thermophoresis parameter, whereas it is elevated significantly with greater Brownian motion parameter. Higher temperatures are achieved with greater thermal relaxation time values, i.e. the non-Fourier model predicts greater values for temperature than the classical Fourier model.