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The purpose of this paper is to analyse the buoyancy flow, mass and heat transfer in coaxial duct under Soret and Dufour effect. The combined effects of the thermal-diffusion and diffusion-thermo coefficients, as well as the Schmidt number, on natural convection in a heated lower coaxial curve were explored using the proposed physical model. The Dufour and Soret effects are taken into consideration in the energy and concentration equations, respectively.

The dominating mathematical models are converted into a set of non-linear coupled partial differential equations, which are solved using a numerical approach. The controlling non-linear boundary value problem is numerically solved using the penalty finite element method with Galerkin’s weighted residual scheme over the entire variety of essential parameters.

It was observed that different parameters were tested such as heat generation or absorption coefficient, buoyancy ratio, Soret coefficient, Dufour coefficient, Lewis number and Rayleigh number. Effect of Rayleigh number, absorption/generation and Dufour coefficient on isotherm are significantly reported. For greater values of Lewis number, maximum mass transfer in duct in the form of molecular particles is produced. Buoyancy ratio parameter decreases the average rate of heat flow and increases its mass transfer.

The main originality of this work is to make an application of Soret and Dufour effects in a coaxial duct in the presence of source sink.

This study aims to deal with the numerical investigation of ferrofluid flow and heat transfer inside a right-angle triangular cavity in the presence of a magnetic field. The vertical wall is partially heated, whereas other walls are kept cold. The effects of thermal radiation are included in the analysis. The governing equations including continuity, momentum and energy equations are converted to nondimensional form using viable variables.

Finite element method (FEM)-based simulations are performed using finite element approach to investigate the effects of the volume fraction of ferroparticles (Fe₃O₄), the length of the heating element and the dimensionless numbers including Rayleigh and Hartmann numbers on the streamlines, isotherms and Nusselt number.

It is demonstrated that both horizontal and vertical velocity components increase with the length of the heating element, whereas the dimensionless temperature decreases the heating domain. It is observed that an increase of 10% in the volume fraction of ferroparticles increases Nusselt number more than 12%, and 20% increase in the volume fraction of ferroparticles increases more than 30%, depending upon the length of the heating element.

This is a new study showing the significance of the magnetic nanoparticles for the enhancement of heat transfer rate in a triangular cavity.

The purpose of this paper is to present an inclusive study of the mixed convective flow involving micropolar fluid holding kerosene/water-based TiO₂ nanoparticle towards a vertical Riga surface with partial slip. The outcomes are confined for opposing and assisting flows.

Similarity equations are acquired and then worked out numerically by the Keller box technique.

Impacts of significant parameters on microrotation velocity, temperature distribution, velocity profile together with the Nusselt number and the skin friction are argued with the help of graphs. Two solutions are achieved in opposing flow, while the solution is unique in assisting flow. It is also monitored that the separation of boundary layer delays because of micropolar parameter and accelerates because of volume fraction.

The authors trust that all these results are new and significant for researchers.

The study aims to numerically examine the impact of nanoparticles on an unsteady flow of a Williamson fluid past a permeable convectively heated shrinking sheet.

In sort of the solution of the governing differential equations, suitable transformation variables are used to get the system of ODEs. The converted equations are then numerically solved via the shooting technique.

The impacts of such parameters on the velocity profile, temperature distribution and the concentration of nanoparticles are examined through graphs and tables. The results point out that multiple solutions are achieved for certain values of the suction parameter and for decelerating flow, while for accelerating flow, the solution is unique. Further, the non-Newtonian parameter reduces the fluid velocity and boosts the temperature distribution and concentration of nanoparticles in the first solution, while the reverse drift is noticed in the second solution.

The current results may be used in many applications such as biomedicine, industrial, electronics and solar energy.

The authors think that the current results are new and significant, which are used in many applications such as biomedicine, industrial, electronics and solar energy. The results have not been considered elsewhere.

This work aims to investigates exact solutions of the classical Glauert’s laminar wall jet mass and heat transfer under wall suction, wall contraction or dilation, and two thermal transport boundary conditions; prescribed constant surface temperature and prescribed constant surface flux in nanofluidic environment.

The flow system arranged in terms of partial dif- ferential equations is non-dimensionalized with suitable dimensionless transformation variables, and this new set of equations is reduced into ordinary differential equations via a set of similarity transformations, where they are treated analytically for closed form solutions.

Exact solutions of nanofluid flow for velocity distributions, momentum flux, wall shear stress and heat transfer boundary layers for commonly studied nanoparticles; namely copper, alumina, silver, and titanium oxide are presented. The flow behavior of alumina and titanium oxide is identical, and a similar behavior is seen for copper and silver, making two pairs of identical traits. The mathematical expressions as well as visual analysis of wall shear drag and temperature gradient which are of practical interest are analyzed. It is shown that wall stretching or shrinking, wall transpiration and velocity slip together influences the jet flow mechanism and extends the original Glauert’s jet solutions. The exact solutions for the two temperature boundary layer conditions and temperature gradients are analyzed analytically. It is found that the effect of nanopar- ticles concentration on thermal boundary layer is intense, causing temperature uplift, whereas the wall transpiration causes a decrease in thermal layers.

The analysis carried out in nanofluid environment is genuinely new and unique, as our work generalizes the Glauert’s classical regular wall jet fluid problem.

This study aims to explore the idea of solving the problem of squeezing nanofluid flow between two parallel plates using a novel mathematical method.

The unsteady squeezing flow is a coupled fourth-order boundary value problem with flow velocity and temperature as the desired unknowns. In the first step, the conditions that guarantee the existence of a unique solution are obtained. Then following Green’s function-based approach, an iterative method for solving the problem is developed.

The accuracy of the method is examined by comparing the obtained results with existing numerical data, indicating excellent agreement between the two. In addition, the effects of nanoparticle shape and volume fraction on the flow and heat transfer characteristics are addressed. The results reveal that although the nanoparticle shape strongly affects the temperature distribution in the squeezing flow, it only has a slight impact on the velocity field. Furthermore, the highest and lowest Nusselt numbers belong to the platelets and spherical nanoparticles, respectively.

A semi-analytical method with computational support is developed for solving the unsteady squeezing flow problem. Moreover, the existence and uniqueness of the solution are discussed for the first time.

This paper aims to analyze the behavior of the stagnation-point flow and heat transfer over a permeable stretching/shrinking sheet in the presence of the viscous dissipation and heat source effects.

The governing partial differential equations are converted into ordinary differential equations by similarity transformations before being solved numerically using the bvp4c function built in Matlab software. Effects of suction/injection parameter and heat source parameter on the skin friction and heat transfer coefficients as well as the velocity and temperature profiles are presented in the forms of tables and graphs. A temporal stability analysis will be conducted to verify which solution is stable for the dual solutions exist for the shrinking case.

The analysis indicates that the skin friction coefficient and the local Nusselt number as well as the velocity and temperature were influenced by suction/injection parameter. In contrast, only the local Nusselt number, which represents heat transfer rate at the surface, was affected by heat source effect. Further, numerical results showed that dual solutions were found to exist for the certain range of shrinking case. Then, the stability analysis is performed, and it is confirmed that the first solution is linearly stable and has real physical implication, while the second solution is not.

In practice, the study of the steady two-dimensional stagnation-point flow and heat transfer past a permeable stretching/shrinking sheet in the presence of heat source effect is very crucial and useful. The problems involving fluid flow over stretching or shrinking surfaces can be found in many industrial manufacturing processes such as hot rolling, paper production and spinning of fibers. Owing to the numerous applications, the study of stretching/shrinking sheet was subsequently extended by many authors to explore various aspects of skin friction coefficient and heat transfer in a fluid. Besides that, the study of suction/injection on the boundary layer flow also has important applications in the field of aerodynamics and space science.

Although many studies on viscous fluid has been investigated, there is still limited discoveries found on the heat source and suction/injection effects. Indeed, this paper managed to obtain the second (dual) solutions and stability analysis is performed. The authors believe that all the results are original and have not been published elsewhere.

The accounting system plays an important role in the company’s organizational structure. The purpose of this paper is to demonstrate that the integration of management accounting practices is subject to coordination between external and internal factors and accounting management practices.

Therefore, the authors move to the contingency model to determine the most significant external “unexpected factors” that explain the introduction of management practices for the management of the various stages of development. The exploratory study examines a sample of Pakistani companies from various sectors.

This study reveals that the main factors of uncertainty that affect the organizational structure, environmental uncertainty, advanced production technology, just-in-time method strategy, integrated management of quality and structure findings reveal that MAP affected all process and changes all system in simple to complex system in Pakistani’s industries.

This study is to acquisition the impact of external factors on management accounting practices, to find the impact of internal factors on management accounting practices, to establish the management accounting practices undertaken by the companies in Pakistan.

The study contributes to the literature by enhancing our understanding for the impact of external and internal factors on management accounting practices in Pakistan.

With a basis in the conservation of resources theory, the purpose of this paper is to investigate the relationship between employees’ experience of time-related work stress and their engagement in counterproductive work behavior (CWB), as well as the invigorating roles that different deviant personality traits might play in this process.

Two-wave survey data with a time lag of three weeks were collected from 127 employees in Pakistani organizations.

Employees’ sense that they have insufficient time to do their job tasks spurs their CWB, and this effect is particularly strong if they have strong Machiavellian, narcissistic or psychopathic tendencies.

This study adds to extant research by identifying employees’ time-related work stress as an understudied driver of their CWB and the three personality traits that constitute the dark triad as triggers of the translation of time-related work stress into CWB.

This paper aims to address stagnation point flow of cross nanofluid in frames of hydromagnetics. Flow analysis subjected to expanding-contracting cylinder is studied.

Nonlinear problems are computed by using bvp4c procedure.

Radius of curvature and temperature-dependent heat sink-source significantly affects heat-mass transport mechanisms for cylindrical surface.

No such analysis has yet been reported.