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EN
This work aims to study the combined effects of concentration and thermal radiation on a steady flow of Jeffrey nanofluid under the Darcy-Forchheimer relation over a flat nonlinear stretching sheet of variable thickness. A varying magnetic field influences normal to the flow movement is considered to strengthen the Jeffery nanofluid conductivity. However, a little effect of the magnetic Reynolds number is assumed to eliminate the impact of the magnetic field range. The higher-order nonlinear partial differential equations (PDEs) and convective boundary conditions are transformed into nonlinear ordinary differential equations (ODEs) by applying corresponding transformations. Then the ODEs are numerically solved with Runge-Kutta method via shooting technique. This process is applied for convergent relations of nanoparticle temperature, concentration, and velocity distributions. The influence of different fluid parameters like thermophoresis, melting parameter, Deborah number, chemical reaction parameter, Brownian motion parameter, inertia parameter and Darcy number on the flow profiles is explained through graphical analysis. Thermal radiation is emitted by accelerated charged particles, and the enhanced particle motion at higher temperatures causes a more significant discharge of radiation. Also, it was concluded that the heat generation parameter enhances the momentum boundary layer thickness and reduces the thermal and solutal boundary layer thickness over a Jeffrey nanofluid.
EN
The present study deals with the analysis of heat and mass transfer for nanofluid flow of blood through an inclined stenosed artery under the influence of the Hall effect. The effects of hematocrit-dependent viscosity, Joule heating, chemical reaction and viscous dissipation are taken into account in the governing equations of the physical model. Non-dimensional differential equations are solved using the finite difference method, by taking into account the no-slip boundary condition. The effects of different thermophysical parameters on the velocity, temperature, concentration, shear stress coefficient and Nusselt and Sherwood numbers of nano-biofluids are exhaustively discussed and analysed through graphs. With an increase in stenosis height, shear stress, the Nusselt number and the Sherwood number are computed, and the impacts of each are examined for different physical parameters. To better understand the numerous phenomena that arise in the artery when nanofluid is present, the data are displayed graphically and physically described. It is observed that as the Hartman number and Hall parameter increase, the velocity drops. This is as a result of the Lorentz force that the applied magnetic field has generated. Blood flow in the arteries is resisted by the Lorentz force. This study advances the knowledge of stenosis and other defects’ non-surgical treatment options and helps reduce post-operative consequences. Moreover, ongoing research holds promise in the biomedical field, specifically in magnetic resonance angiography (MRA), an imaging method for artery examination and anomaly detection.
EN
The present study investigates heat and mass transport phenomena associated with the MHD flow of micropolar fluid over a vertically stretched Riga plate under the action of a uniform magnetic field applied parallel to the plate. The objective of the study is to analyze Soret and Dufour effects on this physical situation in the presence of chemical reaction. The governing partial differential equations are converted into ordinary differential equations using suitable similarity transformations. The equations are solved numerically by developing programming codes in MATLAB for the very efficient shooting method along with the fourth order Runge-Kutta scheme. The velocity, microrotation, temperature and species concentration distribution are presented graphically for various emerging physical parameters like Hartmann number, material parameter, Soret number, Dufour number and other dimensionless parameters. It is found that the species concentration distribution profiles increase with increasing Soret number, whereas the temperature distribution profile decreases with an increasing Soret number. This work also provides solutions for shear stress at plates, the rate of heat and mass transfer in addition to those for velocity, microrotation, temperature and species concentration. Comparisons with previous studies are carefully examined, and it is found that they are generally in agreement.
EN
An accurate parameterization of an irregular surge across a continuously propelled circulation through an endless isothermal inclined plate has been investigated in the presence of a first-degree uniform chemical reaction. Both the plate’s temperature and the proximal intensity are increased systematically. To evaluate non-dimensional equations, the Laplace transform is utilized. The effect of velocity components on a range of physical parameters is investigated which include Sc, Pr, Gr, Gc, α, K and t. A proportionate increase of velocity with Gr and Gc was prominent. τ and Sh were mathematically determined.
EN
The main objective of this exploration is to analyze the effects of heat source/sink, chemical reactions, and radiation on the unsteady free convective flow through a porous medium using an infinitely oscillating vertical plate. The Laplace transformation tactics is utilized to solve the governing equations for concentration, energy, and momentum. The simulation results demonstrate that the chemical reaction parameter dwindles both primary and secondary velocities. It has been noted that an upsurge in heat generation (heat source) enhances the temperature field, while a decrease in heat absorption (heat sink) leads to a reduction in the temperature field. Furthermore, the radiation parameter causes a drop in both temperature and velocity patterns. The equation for skin friction is derived and presented graphically, and 3-dimensional surface plots are provided to depict the Nusselt number and Sherwood number. Additionally, graphical illustrations are employed to showcase the influence of various non-dimensional variables on concentration, temperature, and velocity patterns.
EN
An incompressible unsteady free convective viscous MHD rotating flow past a moving plate embedded in a porous medium is considered with the influence of viscous dissipation, heat source effects. It is assumed that the flow rotates with angular velocity which is normal to the plate and also that a transverse magnetic field is applied along the normal to the plate. Appropriate dimensionless quantities are applied to change the governing equations into dimensionless form. Then the equations are solved numerically using the Galerkin finite element method. Some important characteristics of the fluid are studied. The results are in good agreement with the available literature.
EN
The current article addresses the impacts of the pulsatile flow of Powell-Eyring nanofluid using Buongiorno’s model in a horizontal channel. It also describes the combined impacts of thermophoresis and Brownian motion. Blood is an example of a Powell-Eyring fluid. The Runge-Kutta (R-K) 4th-order method, along with the shooting technique, is used to determine solutions for velocity, temperature, and concentration. The impacts of different parameters, including an inclined magnetic field, chemical reaction, Lewis number, and heat source or sink parameter, are illustrated graphically. The mass flux distribution decreases due to an increase in the values of the Powell-Eyring fluid parameter.
EN
analysis is carried out to study chemically reactive, viscous dissipative effects of an incompressible and electrically conducting fluid with MHD free convection adjacent to a vertical surface with variable thermal conductivity (VTD) and variable mass diffusivity (VMD). An approximate numerical solution for the steady laminar boundary layer flow over a wall of the surface in the presence of species concentration and thermal mass diffusion has been studied. Using numerical techniques the governing boundary layer equations are solved to get the exact solution. Numerical calculations are carried out for different values of dimensionless parameters. The results are exhibited through various graphs and it is observed from the analysis of the results that the velocity field is appreciably influenced by the magnetic effect, porous effect, chemical reaction and buoyancy ratio between the species and thermal diffusion at the wall of the surface.
EN
This article discusses the effect of heat and mass transfer in a boundary layer flow in the presence of a magnetic field of an electrically conducting and viscous fluid as it passes through a porous medium containing a heat source and a chemical reaction. By employing similarity variables, the governing equations are changed into nonlinear ordinary differential equations(ODEs). To solve the obtained equations numerically the Keller box method is used. Numerical and graphical representations of the results of different parameter values governing the flow system are given. The non-dimensional distributions of velocity, heat, and concentration are depicted graphically, while the Nusselt number, Sherwood number, and skin friction are determined numerically.
EN
This study investigates the unsteady MHD flow of a fourth-grade fluid in a horizontal parallel plates channel. The upper plate is oscillating and moving while the bottom plate is stationary. Solutions for momentum, energy and concentration equations are obtained by the He-Laplace scheme. This method was also used by Idowu and Sani [12] and there is agreement with our results. The effect of various flow parameters controlling the physical situation is discussed with the aid of graphs. Significant results from this study show that velocity and temperature fields increase with the increase in the thermal radiation parameter, while velocity and concentric fields decrease with an increase in the chemical reaction parameter. Furthermore, velocity, temperature and concentric fields decrease with an increase in the suction parameter. It is also interesting to note that when 4S0=, our results will be in complete agreement with Idowu and Sani [12] results. The results of this work are applicable to industrial processes such as polymer extrusion of dye, draining of plastic films etc.
EN
A mathematical model is presented for analyzing the convective fluid over a stretching surface in the presence of nanoparticles. The analysis of heat and mass transfer of converted fluid with slip boundary condition is investigated. To convert the governing Partial Differential Equations (PDEs) into a system of nonlinear Ordinary Differential Equations (ODEs) we use similarity transformations. The shooting method is used to solve the system of ODEs numerically, and obtained numerical results are compared with the published results and found that both are in excellent agreement. The numerical values obtained for the velocity, temperature and concentration profiles are presented through graphs and tables. A discussion on the effects of various physical parameters and heat transfer characteristics is also included.
EN
In this paper, a theoretical analysis has been made to study the effect of mixed convection MHD oscillatory Couette flow in a vertical parallel channel walls embedded in a porous medium in the presence of thermal radiation, chemical reaction and viscous dissipation. The channel walls are subjected to a constant suction velocity and free stream velocity is oscillating with time. The channel walls are embedded vertically in a porous medium. A magnetic field of uniform strength is applied normal to the vertical channel walls. The nonlinear and coupled partial differential equations are solved using multi parameter perturbation techniques. The effects of physical parameters, viz., the radiation absorption parameter, Prandtl number, Eckert number, dynamic viscosity, kinematic viscosity, permeability of porous medium, suction velocity, Schmidt number and chemical reaction parameter on flow variables viz., temperature, concentration and velocity profile have been studied. MATLAB code is used to analyze theoretical facts. The important results show that an increment in the radiation absorption parameter and permeability of porous medium results in an increment of the temperature profile. Moreover, an increment in the Prandtl number, Eckert number and dynamic viscosity results in a decrement of the temperature profile. An increment in suction velocity results in a decrement of the velocity profile. An increment in the Schmidt number, chemical reaction parameter and kinematic viscosity results in a decrement of the concentration profile.
EN
A numerical study on a steady, laminar, boundary layer flow of a nanofluid with the influence of chemical reaction resulting in the heat and mass transfer variation is made. The non-linear governing equations with related boundary conditions are solved using Adam’s predictor corrector method with the effect of a Brownian motion and thermophoresis being incorporated as a model for the nanofluid, using similarity transformations. Validation of the current numerical results has been made in comparison to the existing results in the absence of chemical reaction on MHD flows. The numerical solutions obtained for the velocity, temperature and concentration profiles for the choice of various parameters are represented graphically. Variations of heat and mass transfer across a Brownian motion and thermophoresis are studied and analyzed.
EN
The impact of heat and mass transfer effects on an MHD flow past an inclined porous plate in the presence of a chemical reaction is investigated in this study. An effort has been made to explain the Soret effect and the influence of an angle of inclination on the flow field, in the presence of the heat source, chemical reaction and thermal radiation. The momentum, energy and concentration equations are derived as coupled second order partial differential equations. The model is non-dimensionalized and shown to be controlled by a number of dimensionless parameters. The resulting dimensionless partial differential equations can be solved by using a closed analytical method. Numerical results for pertaining parameters, such as the Soret number (Sr), Grashof number (Gr) for heat and mass transfer, the Schmidt number (Sc), Prandtl number (Pr), chemical reaction parameter (Kr), permeability parameter (K), magnetic parameter (M), skin friction (τ), Nusselt number (Nu) and Sherwood number (Sh) on the velocity, temperature and concentration profiles are presented graphically and discussed qualitatively.
EN
This paper focuses on the theoretical analysis of blood flow in the presence of thermal radiation and chemical reaction under the influence of time dependent magnetic field intensity. Unsteady non linear partial differential equations of blood flow consider time dependent stretching velocity, the energy equation also accounts time dependent temperature of vessel wall and the concentration equation includes the time dependent blood concentration. The governing non linear partial differential equations of motion, energy and concentration are converted into ordinary differential equations using similarity transformations solved numerically by applying ode45. The effect of physical parameters, viz., the permeability parameter, unsteadiness parameter, Prandtl number, Hartmann number, thermal radiation parameter, chemical reaction parameter and Schmidt number on flow variables, viz., velocity of blood flow in vessel, temperature and concentration of blood, has been analyzed and discussed graphically. From the simulation study the following important results are obtained: velocity of blood flow increases with the increment of both permeability and unsteadiness parameter. The temperature of blood increases at the vessel wall as the Prandtl number and Hartmann number increase. Concentration of blood decreases as time dependent chemical reaction parameter and Schmidt number increases.
EN
A free convection viscous MHD flow over a semi-infinite vertical sheet with convective heat and mass conditions has been considered. The effects of thermal radiation, chemical reaction and Joule heating on flow are also accounted. The governing nonlinear partial differential equations have been transformed into a set of highly non-linear coupled ordinary differential equations (ODEs) using appropriate similarity transformations. Numerical solutions of transformed equations are obtained by employing the 5th order Runge-Kutta Fehlberg technique followed by the shooting technique. The influences of different flow parameters on the momentum, energy and mass field are discussed and shown graphically. Results reveal that temperature and concentration profiles enhance due to increasing heat and mass Biot number parameters.
EN
The characteristic of nano sized particles mass flux conditions are engaged in this investigation. Here we assume that the nano sized particle flux is zero and the nano sized particle fraction arranged itself on the boundary layer. With this convincing and revised relation, the features of Buongiorno relation on three-dimensional flow of Carreau fluid can be applied in a more efficient way. The governing partial differential equations of continuity, momentum, energy and concentration equations which are transmitted into set of pair of nonlinear ordinary differential equations utilizing similar transformations. The numeric solutions are acquired by engaging the bvp4c scheme, which is a finite-difference code for solving boundary value problems. A parametric study is accomplished to demonstrate the impact of Prandtl number, Weissenberg numbers, radiation parameter, chemical reaction parameter, thermophoresis parameter, Brownian motion parameter and Lewis number on the fluid velocity, temperature and concentration profiles as well skin friction coefficient, Nusselt number and Sherwood number within the boundary layer. From this we find the way in which magnetic parameter contributes to the increase in local skin fraction, and the decrease in the Nusselt and Sherwood numbers in these cases. The effects of the velocity temperature and concentration profile are obtained and presented graphically.
18
Content available Sea transportation of coal liable to liquefaction
EN
The marine industry is a vital link in the international trade, with vessels representing the most efficient, and often the only method of transporting large volumes of raw materials. Coal is a major cargo with hundreds of millions of tons being shipped every year for power consumption and industrial uses. The vast majority of coal traded is delivered by sea. The IMSBC Code specifies requirements related to the safe stowage and shipment of coal that may give rise to relevant on-board risks, for example structural damage due to improper coal distribution, chemical reaction leading to spontaneous combustion, emission of explosive gases and liquefaction. As coal is liable to liquefaction, several precautions should be taken before accepting the cargo for shipment and procedures for safe loading and carriage should be respected. According to the analysis of the data, the proportion of fines in the cargoes shipped worldwide has been accepted as an appropriate criterion to identify the potential of a coal cargo for liquefaction. The main purpose of this paper is to investigate the impact of coal properties on the ability to liquefy. The relation between the degree of fragmentation and the value of the TML was analyzed. In addition, the possibility of using different method for determination of the TML was discussed.
EN
An analytical solution of an MHD free convective thermal diffusive flow of a viscous, incompressible, electrically conducting and heat-absorbing fluid past a infinite vertical permeable porous plate in the presence of radiation and chemical reaction is presented. The flow is considered under the influence of a magnetic field applied normal to the flow. The plate is assumed to move with a constant velocity in the direction of fluid flow in slip flow regime, while free stream velocity is assumed to follow the exponentially increasing small perturbation law. The velocity, temperature, concentration, skin friction, Nusselt number and Sherwood number distributions are derived and have shown through graphs and tables by using the simple perturbation technique.
EN
An analysis is presented to study the effects of thermal radiation, chemical reaction, viscous and Joule dissipation on MHD free convection flow between a pair of infinite vertical Couette channel walls embedded in a porous medium. The fluid flows by a strong transverse magnetic field imposed perpendicularly to the channel wall on the assumption of a small magnetic Reynolds number. The governing non linear partial differentia equations are transformed in to ordinary differential equations and are solved analytically. The effect of various parameters viz., Eckert number, electric conductivity, dynamic viscosity and strength of magnetic field on temperature profile has been discussed and presented graphically.
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