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In this research paper, we have study about the heat and mass transfer effects of rotation and porosity of the medium on unsteady convection flow of a viscous, incompressible, and electrically conducting flow past a started vertical plate under the influence of transversely applied uniform mass diffusion. The Laplace-transform technique is used to solve the governing equations in this investigation. The results are described using graphs for various factors such as the thermal Grashof number, the mass Grashof number, the Prandtl number, the permeability parameter, and the Schmidt number. The goal of this research is to look at the rotation and porosity of the medium in a flow model. The velocity in the boundary layer was found to be higher in the study. The non-dimensional equations are solved and programmed in MATLAB R2020. Finally, it can be shown that the speed increases when warm Grashof or mass value evaluations are made. The significance of the problem can be observed in the cooling of nuclear reactor electronic components. [ABSTRACT FROM AUTHOR]

A numerical investigation is carried out for mixed convection fluid flow and heat transfer in a discretely heated lid-driven square cavity. The fluid in the cavity is a water-based nanofluid containing Al2O3 nanoparticles. The bottom and left walls are discretely heated while the right wall is cooled. The top wall is considered adiabatic and moving at a constant speed. The numerical resolution of the studied problem is based on the lattice Boltzmann method (LBM). The simulations have been carried out for the effects of various controlling parameters, such as Grashof number being fixed at 104, Richardson number ranging from 0.05 to 10, inclination angle ranging from 0° to 90° and the solid volume fraction of nanoparticles between 0 and 0.07. The obtained results are presented as streamlines, isotherms, average Nusselt numbers and average temperature inside the cavity. Results show that the nanoparticles effect contributes to an enhancement on heat transfer rate. Also, it is found that Ri involves a heat transfer reduction on both left and bottom walls. [ABSTRACT FROM AUTHOR]

In the setting of a synthetic activity with variable material dispersion, the magnet ohydro dynamics (MHD) influence on intermittent spontaneous convection circulation of a sticky inviscid stream of an isothermal endless undulating straight slab is examined. The heat index of the panel is elevated to Qw, and the dosage close the surface increases exponentially with duration. When the sheet undulates sonically in its own surface, the Laplace Transform approach yields an accurate approximation to the non-dimensional regulating formulae. For various factors such as magnetic field, phase orientation, Schmidt number, synthetic reactivity, thermal and mass Grashof numbers, and duration, the consequences of velocity, temperature, as well as concentration are examined. It is found that when the phase inclination decreases, the velocity rises. It is also noted that when the magnetic field value lowers, the pace rises. [ABSTRACT FROM AUTHOR]

The existing study of the paper using chemical reaction examines the consequences of thermal and mass transferal on MHD Alumina nanofluid energy passed over an oscillatory plate by radiation. Using similarity transformations, the governing equations are reformed into dimensionless equations and solved through Laplace Transformation. The effects of parameters in radiation (R), Schmidt number (Sc), Prandtl number (Pr), magnetic parameter (M), chemical Reaction Parameter (Kc), solid volume fraction (ϕ), thermal Grashof number (Gr), mass Grashof number (Gc), phase angle (ω) are scrutinized in velocity, temperature, and concentration forms. The depicted charts are shown the enhancement of the velocity, temperature, and concentration. It observes that an increment of magnetohydrodynamic diminishes the velocity, an increment of thermal and mass Grashof number stand out towards the increase through the velocities, and increasing radiation reduces a temperature. An increment of Schmidt number diminishes the concentration of the Alumina nanofluid. The Concentration of the fluid decreases as an increment of chemical reactive parameters. The increment in time directs to increase the Nusselt number along with the Sherwood number. The skin friction Coefficient improvements with accumulative values of mass grashof number and radiation. [ABSTRACT FROM AUTHOR]

The present parametric study focuses on the mixed convection conjugate heat transfer in a differentially heated lid-driven skew cavity with a thick bottom wall. The bottom wall of the solid is isothermally heated. An in-house solver based on the SIMPLE algorithm is developed in the OpenFOAM environment to solve the governing equations using the Finite Volume Method. The flow parameters and heat transfer characteristics were numerically investigated for a broad range of skew angles (0° ≤ θ ≤ 45°) and Richardson number (0.01 ≤ Ri ≤ 10). Reynolds number (Re) is varied in the range 31.62 ≤ Re ≤ 1000, and Grashof number (Gr) is fixed at 104. The local Nusselt number (Nux) and average Nusselt Number ( N u ¯ ) are evaluated on the top wall to illustrate the heat transfer characterization in the computational domain. The flow field and heat transfer are sensitive to skew angle as well as Ri variation. As Ri increases, heat transfer decreases for a fixed value of skew angle of the cavity. However, at higher values of Ri, where the buoyancy effect is dominant, heat transfer augmentation has been observed as skewness of the cavity is increased. [ABSTRACT FROM AUTHOR]

This paper analyses the spread of spilled oil through the soil. The effect of two dimensional porosity variations on the subsurface is investigated. The variations in porosity are described by the mean porosity, empirical constant and particle diameter. The coupled non linear system of differential equations are solved using perturbation method. The effect of various parameter such as porous, Prandtl number, Grashof number, Dufour number, Eckert number, chemical reaction parameter, Schmidt number, Soret number, retardation factor and porosity are discussed with the graphs. [ABSTRACT FROM AUTHOR]

A numerical simulation is carried out for the mixed convection heat transfer of Cu-water nanofluid inside a three-dimensional double lid-driven cavity, heated differentially. The momentum and energy equations are solved using the finite volume method, adopting the power law as a resolution scheme. The results are presented over a wide range of Richardson number (0.03 - 100), volume fractions of nanoparticles (0 - 0.06), fixed Grashof number 104 and different direction of the lids (case1: the upper lid moves left and the hot lid moves down, case 2: the upper lid moves left and the hot lid moves upward). The results are analyzed and presented in the form of streamlines, isotherms and average Nusselt number. The results show that case 2 gives the best heat transfer performance. The results also indicate that increasing Richardson number the temperature gradient decrease and the distribution of temperature inside the cavity becomes more uniform. [ABSTRACT FROM AUTHOR]

Conjugate pure mixed convection in a lid-driven differentially heated square cavity with two rotating and heat conducting cylinders is numerically investigated by using the finite element method. Three different cases based on the movement of the vertical lids (left and right walls) are considered in this study. The two-dimensional mathematical model includes the system of four partial differential equations of continuity, linear momentum and energy. Flow and thermal fields are investigated for air flowing inside the cavity with four combinations of cylinder rotation, i.e., rotating each cylinder either in clockwise or counterclockwise direction at constant rotational speed, for each different case of direction of lid movement. Parametric simulation is performed with the variation of both Reynolds and Grashof numbers within the range of 10 ≤ Re ≤ 2000 and 100 ≤ Gr ≤ 4 × 106 at fixed Richardson number (Ri = 1). The computational results show that flow patterns and thermal transport within the cavity are greatly affected by the variation of Reynolds number, direction of lid movement and direction of cylinder rotation. It has been observed that the overall heat transfer is remarkably enhanced when only the left lid moves downward and both cylinders rotate in counterclockwise direction. [ABSTRACT FROM AUTHOR]

An attempt is made to analyse the effects of skin friction on unsteady flow past a moving vertical plate in a rotating fluid with variable temperature and mass diffusion. An analytical solution is obtained by considering a complex velocity with the axial and transverse components. The effects of skin friction for the parameters like Schmidt number, radiation parameter, thermal Grashof number Prandtl number, rotation parameter and mass Grashof number on the plate are observed and analysed. [ABSTRACT FROM AUTHOR]

This work reports the numerical study of unsteady laminar boundary layer flow of viscous, electrically conducting. incompressible, fluid in a channel filled with a porous medium along with a semi-infinite vertical plate in the presence of uniform mass diffusion and transverse magnetic field. The finite element method, Galerkin is used to solve the governing equations. The flow phenomenon has been calculated with the help of flow parameters such as velocity, temperature and concentration profiles for different parameters such as. Schmidt number, Prandtl number, Magnetic field, Chemical reaction Parameter, Permeability parameter, Chemical reaction, Soret number and Grashof number. The velocity, temperature, and concentration are observed graphically. The coefficient of skin-friction, Nusselt number, and Sherwood number are calculated. [ABSTRACT FROM AUTHOR]

The present paper investigates the flow analysis of an incompressible Jeffrey fluid with nano particles in an inclined tube with overlapping stenosis. The solutions for velocity, wall shear stress, resistance to the flow have been derived by considering mild stenosis. It is observed that the resistance to the flow increases with stenosis height and also with Jeffrey fluid parameter and thermophoresis parameter, but it decreases with Brownian motion number, local nanoparticle Grashof number, local temperature Grashof number, and angle of inclination. It is also noticed that wall shear stress increases with Brownian motion number but decreases with thermophoresis parameter, Jeffrey fluid parameter, and inclination. [ABSTRACT FROM AUTHOR]

The intention of the current analysis is to examine mathematical model of blood flows through a tube with stenosis and dilatation under the influence of steady and incompressible micropolar fluid with nanoparticles. Coupled non-linear equations are solved by HPM method analytically. Effects of different physical parameters like micropolar parameter, coupling number, Brownian motion parameter, thermophoresis parameter, local temperature and nanoparticle Grashof number on flow resistance, shear stress at wall of the fluid are investigated. Effects of relevant parameters on arterial blood flow characteristics are studied through the graphs. It is seen that, the flow resistance enhances with the micropolar parameter, thermophoresis parameter, local temperature and nanoparticle Grashof number. But reduces with Brownian motion parameter and coupling number. [ABSTRACT FROM AUTHOR]

The target of this paper is to consider transient Magnetite-Water nanofluid flow and heat transfer from a vertical oscillating plate in the presence of magnetic field. Unconditionally stable finite difference numerical solution is developed for the governing non-linear partial differential equations with appropriate initial and boundary conditions. The impact of controlling parameters, for example, nanoparticle volume fraction, magnetic parameter, thermal Grashof number, and phase angle on the velocity, temperature, skin friction coefficient and Nusselt number of engineering significance has been introduced in charts and talked about. [ABSTRACT FROM AUTHOR]

The effect of slip on Non-Newtonian fluid in a circular tube of non-uniform cross section with multiple stenoses has been studied. The coupled equations in temperature and nanoparticle phenomena are calculated by using Homotopy Perturbation Method. Assuming the stenoses to be mild, the expressions for the flow characteristics, like, pressure drop, resistance to the flow and shear stress at the wall have been determined and solutions have been obtained. It is observed that the resistance to the flow increases with the heights of the stenosis, Brownian motion number, Thermophoresis parameter, local temperature Grashof number, local nanoparticle Grashof number, inclination and permeability constant. Moreover, the shear stress at the wall increases with Brownian motion parameter and with height of the stenosis, but decreases with local nanoparticle Grashof number, Thermophoresis parameter and permeability constant. [ABSTRACT FROM AUTHOR]

In this article, we perceived the amplification of heat transfer of viscous incompressible kerosene oil based nanofluid past a porous plate accompanied by viscous dissipation. A robust Galerkin type numerical finite element technique is adopted to solve the equations which model the flow. The alterations in velocity and temperature for diverse values of appropriate parameters such as suction parameter (λ), Eckert Number (E), volume fraction (δ), thermal Grashof number (G) are examined in the form of graphs and for skin friction coefficient as well as Nusselt number in the form of tables. This study contributes to enhance the cooling/heating performance of industrial and engineering systems. [ABSTRACT FROM AUTHOR]

In this work MHD effect on mixed convection heat transfer of nanofluid in a vented parallelogrammic cavity with injection or suction is studied numerically using Cu-water nanofluid as working fluid. Galerkin weighted residual finite element method is used to solve the two dimensional problem. The bottom wall is subjected to be linearly heated temperature and top wall is cold temperature, while the other boundaries are considered thermally insulated. The pure water is admitted from the left vertical wall in bottom portion by injection or by the suction imposed on the opening of the right vertical wall. A set of graphical results are presented in terms of streamlines, isotherms, dimensionless temperature, velocity profiles and average Nusselt numbers to investigate the effect of Hartmann number, Reynolds number, Grashof number and Richardson number on the fluid flow and heat transfer characteristics inside the enclosure. The results demonstrate that heat transfer rate increases as increasing Richardson number. It is observed that Hartmann number is a good control parameter for heat transfer in fluid flow through parallelogrammic enclosure. Moreover, Cu-water nanofluid has significant effect to be used for enhancing the heat transfer rate. To validate the computational procedure present result compared with other published works. [ABSTRACT FROM AUTHOR]

The present numerical study has been conducted to explore on the effects of external magnetic field at different angle of inclination on the flow driven by the combined mechanism of buoyancy and thermo-capillary flow in an open enclosure. The enclosure is provided with localized heating from below and symmetric cooling is assumed from sides. Along the free surface on the top of the enclosure, the surface tension varies with temperature difference which is known as the Marangoni effect and also called the thermo-capillary effect. The governing equation of the system (i.e. mass, momentum and energy) are presented in the non-dimensional form along with necessary boundary conditions and hence been solved numerically by Galerkin finite element method (FEM) with triangular discretization system. The effect of pertinent parameters such as Hartmann number (0 < Ha < 100), angle of inclination of the magnetic field (0° < Φ < 90°), Grashof number (10³ < Gr < 106), Marangoni number (-100 < Ma < 100) and Prandtl number (0.7 < Pr < 7) on the isotherms, streamlines inside the enclosure as well the heat transfer performance of the system have been explored for various parametric conditions of the system. One key observation is flow field changes drastically with angle of inclination in the presence of the Marangoni effect. And also the heat transfer increases at higher Prandtl number and Grashof number. [ABSTRACT FROM AUTHOR]

In this paper, numerical analysis of laminar mixed convection of an isothermally heated vertical channel has been carried out using finite element method. Both of the side walls of the vertical channel are maintained at constant high temperature, whereas the inlet air follows Poiseuille’s velocity profile at cold temperature. To solve this problem, two dimensional Navier-Stokes and energy equations are considered as the governing equations. The variation of flow characteristics are obtained from fixed Grashof number (Gr = 100; Re = 10, 100, 500), fixed Reynolds number (Re = 100; Ri = 0.1, 1, 10) and fixed Richardson number (Ri = 1; Re = 10, 100, 500). The results are presented in terms of isotherms, streamlines, temperatures and velocity profiles across the channel. The results showed that the average Nusselt number on the hot walls increases with the increment of Re at constant Gr. Similar enhancement of heat transfer is observed with the decrement of Ri while Re is kept constant. [ABSTRACT FROM AUTHOR]

In this paper an oscillatory stream of anelectrically and viscoelasticleading liquid through a porous medium limited by two interminable vertical similar plates is talked about within the sight of heat source and radiation with impact of mass transfer and slip parameter. One of these plates is exposed to a slip-stream condition and other to a no-slip condition. The weight inclination in the channel wavers with time. An attractive field of uniform quality is connected toward the path opposite to the plates. The initiated attractive field is disregarded because of suspicion of little attractive Reynolds number. The temperature contrast of the two plates is additionally accepted sufficiently high to instigate heat transfer because of radiation. A shut form investigative answer for the issue is acquired. The investigative outcomes are assessed statistically and afterward exhibited graphically to talk about in part the impacts of various relevant constraints going into the issue. It is established that the speed profiles increment because of increment in Reynolds number or there is increment in Grashof number for mass transfer and a switch number is noted on the profiles of the speed at whatever point there is an expansion in either attractive parameter or heat source parameter. [ABSTRACT FROM AUTHOR]

A numerical method is applied to compare the effects of heat transfer of a copper waternanoflud and an Aluminum oxide water nanofluid by natural convection over a horizontally inclined plate. The Velocity and Temperature profiles for the effects of different parameter Angle I, Grashof number Gr, and nanoparticle volume fraction are analyzed and presented in graphs. The present results are validated by comparing it with the results in the open literature. [ABSTRACT FROM AUTHOR]

This present paper investigates the impact of radiation on liquid stream and warmth and mass exchange over a vertically swaying permeable level plate installed in permeable medium with wavering surface temperature. Mass transfer effects are added into the governing equations. The analytic solutions of the velocity, temperature and concentration profiles are obtained. The effect of physical parameters Prandtl number Pr, Grashof number Gr, Suction parameter S, Magnetic parameter, Darcy number and radiation parameter R, Schmidt number Sc, Modified Grshof number Gc on the velocity, temperature and concentration profiles are analysed and the results are depicted through graph. [ABSTRACT FROM AUTHOR]

In this paper MHD convective flow of two immiscible fluids flow in the presence of magnetic in inclined channels are investigated. The different temperature T1 and T2 are maintained between the channels. The flows of the basic governing equations of the problem are converted into ODE by using non dimensional quantities. The governing equations are solved by the regular perturbation method. Then the results of the momentum and energy equations are solved numerically and graphically. The effect of various types of parameters like Grashof number ‘Gr’, Hartman number ‘M’, thermal conductivity ‘K’, viscosity ratio ‘m’, the angle inclination ‘α’ in the velocity fields and temperature field, Height ratio ‘h’, thermal conductivity ‘K’ and Heat absorption ‘ Ω ’ are analyzed graphically. [ABSTRACT FROM AUTHOR]

The present study has analyzed the viscous dissipation effects on magneto hydrodynamic nanofluid along a plate inclined at an angle α in a permeable medium subject to uniform heat and mass flux. The perturbation technique is implied to solve the governing equations and to discuss the details of the pertinent of parameters effects. In addition to water as its base fluid a Copper (Cu) nano particle has been exclusively chosen. The combined effects of Eckert number and magnetic parameter on velocity and temperature profiles are discussed. The obtained results for the effects of Prandtl number, Schmidt number, thermal Grashof number, nano particle volume fraction viscous dissipation and porous medium parameter on velocity, temperature and concentration are examined diagrammatically. [ABSTRACT FROM AUTHOR]

The interaction between the fluid flow in a channel and transversely rotating cylinders across the flow field has a great impact on heat transfer rate. The purpose of this study is to investigate numerically the heat transfer enhancement from multiple discrete heaters placed in an inclined rectangular channel with rotating cylinders inserted above each of the heaters. The whole computation was analyzed for a 2D rectangular channel with upper wall is maintaining a constant low temperature and the bottom wall is provided with multiple discrete isoflux flat heaters connected by adiabatic segments. At inlet, a fully developed parabolic velocity profile at constant low temperature has been induced. Air has been considered as working fluid. The system has been represented mathematically by different sets of governing equations, which are solved by using Galerkine Finite Element method. The effect of the variation of rotating speeds of the cylinders in terms of the cylinder peripheral speed to maximum inflow velocity (ξ), Grashof number (Gr) and channel inclination angle (α) were numerically investigated for the range of 103 ≤ Gr ≤ 106, 0° ≤ α ≤ 90°, 0.5 ≤ ξ ≤ 2.0 at fixed Reynolds number, Re = 100. Temperature field and flow field are investigated in terms of isotherm lines (θ) and stream lines (Ψ) respectively. Heat transfer characteristics are also demonstrated in terms of Normalized Nusselt number (Nu/Nunc) and Local Nusselt number (Nul). The results reveal that insertion of rotating cylinders above heaters increases heat transfer rate from 32% to 55% for all speed ratios (ξ) for the values of Grashof number 103≤ Gr ≤ 105 and then start to decrease but still remains about 12% to 22% higher than no cylinder condition at Gr = 106. [ABSTRACT FROM AUTHOR]

This present article address the analytical and numerical study of convective flow in partially heated channel filled by the porous media. The flow in the channel is due to outer pressure gradient and partial heating at walls. For this study we have used the extension of Darcy model, which is known as Brinkman-extended or Forchheimer-extended models. The porous media is assumed hydro-dynamical isotropic. The Chebyshev spectral collocation method is used to find the numerical solution of governing differential equations. In this study our aim is to compare the numerical solution obtained by spectral collocation method with the analytical solution for the particular case when Forchheimer number (Fr) is zero. It is found that the relative error is less than 10-11. The impact of Grashof number (Gr), Forchheimer number (Fr) and Darcy number (Da) on the velocity profile is also presented. It is observed that on increasing Grashof number (Gr) the velocity profile is possesses a critical point Y = 0 at which the velocity contour changes its concavity. It's is also observed that there exist a certain value of Gr after which the back flow start at the wall of channel. It's found that as media of permeability is reduced by decreasing Da and increasing F the velocity is diminished and the critical point at which velocity change its concavity is also perished from the velocity contour. [ABSTRACT FROM AUTHOR]

Numerical simulation of steady two-dimensional heat transfer in a rectangular channel with a centered variable speed cylinder has been performed in this paper. In this setup, an isoflux heater is placed at the bottom wall of the channel while the upper wall is kept isothermal with a low temperature. The cylinder's peripheral speed to maximum inlet fluid velocity ratio (ξ) is varied from 0.5 to 1.5 for both clockwise and anticlockwise rotational cases. Air has been considered as working fluid while other system parameters such as Grashof and Reynolds numbers are varied. The effects of rotational speed, Grashof and Reynolds numbers on the streamline pattern, isothermal lines, local and average Nusselt number are analyzed and presented. It is observed the cylinder's rotational direction and speed has a significant effect on the flow pattern, temperature distribution as well as heat transfer characteristics. [ABSTRACT FROM AUTHOR]

The physical model considered here is a lid-driven porous square cavity with internal elliptic shape adiabatic block and linearly heated side walls. The top moving wall is well cold and set with uniform velocity. The bottom moving wall heated, linearly heated side walls and inside the elliptic shape adiabatic. The relevant parameters in the present study are Darcy number Da = 10-5-10-3, Grashof number Gr = 10³-105, Reynolds number Re = 1-10² and Prandtl number Pr = 0.7. The isotherms are also almost symmetric at small Re with higher Gr (Gr = 105) and Da (Da = 10-3) and natural convection is found to be dominant whereas the isotherms are compressed near the left and bottom walls at higher Re for linearly heated side walls. The solution of these governing equations is obtained numerically with the finite element approach using the Galerkin method of weighted residuals. Results are presented in the form of streamlines, isotherms, Local Nusselt number, average Nusselt number, velocity and temperature for the afore mentioned parameters. The numerical results indicate the strong influence of the mentioned parameters on the flow structure and heat transfer as well as average Nusselt number. An optimum combination of the governing parameters would result in higher heat transfer. [ABSTRACT FROM AUTHOR]

An analytical analysis has been carried out to study the MHD flow and heat transfer of Williamson fluid over a cone and wedge with heat source/sink. The governing equations are transformed into ordinary differential equations by using similarity variables. The analytical solutions of the transformed governing equations are obtained by using homotopy analysis method. The effects of various physical parameters such as Hartmann number, local Williamson parameter, local Grashof number and heat source/sink parameters on velocity, temperature skin friction and heat transfer rate have been discussed in detail. Further, a comparative study has been performed with earlier works that are reported in the literature. The comparison shows that the results are in excellent agreement. [ABSTRACT FROM AUTHOR]

This article discussed the effect of ramped wall temperature on rotating second grade fluid in mixed convection flow. The unsteady two dimensional momentum and energy equations of the incompressible fluid are modelled in the form of partial differential equations with initial and oscillating boundary conditions. The governing equations are transformed into non dimensional equations by using the corresponding non dimensional variables. The Laplace transform method is applied into non dimensional equations in order to obtain the analytical solutions of velocity and temperature profiles. Computations are carried out and presented graphically to analyse the effect of second grade fluid parameter, rotation parameter, Grashof number, phase angle, Prandtl number and time on the profiles. It is found that, when Grashof number increases, the velocity increases in primary and secondary velocities. Both velocity and temperature are observed decrease when phase angle and Prandtl number increase. It can be concluded that, the velocity profiles in rotating flow obtained in this study is lower to compare with non-rotating flow. Whereas, the temperature profiles are remain the same for both cases. It is worth to mention that, the exact solutions obtained in this study can be used to check the correctness of the results obtained through numerical schemes. [ABSTRACT FROM AUTHOR]

A numerical analysis is carried out to study the performance of steady laminar mixed convection flow inside a square lid-driven cavity filled with water-Al2O3 nanofluid. The top wall of the cavity is moving at a constant velocity and is heated by an isothermal heat source. Two-dimensional Navier-stokes equations along with the energy equations are solved using Galerkin finite element method. Results are obtained for a range of Reynolds and Grashof numbers by considering with and without the presence of nanoparticles. The parametric studies for a wide range of governing parameters in case of pure mixed convective flow show significant features of the present problem in terms of streamline and isotherm contours, average Nusselt number and average temperature profiles. The computational results indicate that the heat transfer coefficient is strongly influenced by the above governing parameters at the pure mixed convection regime. [ABSTRACT FROM AUTHOR]

Unsteady laminar flow with convective heat transfer through a curved square duct rotating at a constant angular velocity about the center of curvature is investigated numerically by using a spectral method, and covering a wide range of the Taylor number -300≤ Tr ≤ 1000for the Dean number Dn = 1000. A temperature difference is applied across the vertical sidewalls for the Grashof number Gr = 100, where the outer wall is heated and the inner wall cooled, the top and bottom walls being adiabatic. Flow characteristics are investigated with the effects of rotational parameter, Tr, and the pressure-driven parameter, Dn, for the constant curvature 0.001. Time evolution calculations as well as their phase spaces show that the unsteady flow undergoes through various flow instabilities in the scenario 'multi-periodic → chaotic → steady-state → periodic → multi-periodic → chaotic', if Tr is increased in the positive direction. For negative rotation, however, time evolution calculations show that the flow undergoes in the scenario 'multi-periodic → periodic → steady-state', if Tr is increased in the negative direction. Typical contours of secondary flow patterns and temperature profiles are obtained at several values of Tr, and it is found that the unsteady flow consists of two- to sixvortex solutions if the duct rotation is involved. External heating is shown to generate a significant temperature gradient at the outer wall of the duct. This study also shows that there is a strong interaction between the heating-induced buoyancy force and the centrifugal-Coriolis instability in the curved channel that stimulates fluid mixing and consequently enhances heat transfer in the fluid. [ABSTRACT FROM AUTHOR]

The investigation on hydromagnetic flow of dusty fluid with Hall effect over a vertical surface of stretching sheet has been conducted. The governing partial differential equations are transformed into ordinary differential equations by using similarity transformation. The resulting differential equations are solved numerically by using Runge Kutta Fehlberg forth-fifth method (RKF45 Method). The effects of magnetic parameter, fluid-particle interaction parameter, Grashof number and Hall parameter on velocity and temperature profiles are presented graphically. The numerical values of the velocity gradient and wall temperature gradient are also shown in a tabular form. [ABSTRACT FROM AUTHOR]

An exact solution is presented for the problem of unsteady natural convective radiating flow in an open-ended vertical channel. Laplace transform technique is used to obtain the analytical solutions for the velocity and temperature fields in the optically thin limit case when the channel walls temperature are maintained at different constant temperatures. The effects of radiation parameter and Grashof number on the flow fields are discussed through graphs. It is found that the effect of radiation is to decrease the fluid velocity whereas the effect of Grashof number is to increase the fluid velocity in the vertical channel. [ABSTRACT FROM AUTHOR]

Fluid mechanics and heat transfer of a power law non Newtonian binary alloy are described inside the annular space between concentric horizontal cylinders. Liquid to solid phase transformation, originated by external forced convective cooling through the thick walls of the cylindrical mold is described by a temperature dependent liquid phase change fraction. Governing nonlinear coupled continuity, linear momentum and energy partial differential equations are solved by using the finite volume method. Effects of Grashof number and radii ratio are investigated for pseudo plastics (n=0.2) and dilatant (n=1.5) flow behaviors of the Al-1.7wt%Si alloy. Results for the time evolution of velocity, streamlines and temperature are presented for both Newtonian and non- Newtonian cases. The presence of multicellular flows is found to increase as the power law index decreased from 1.0, and the Rayleigh number and the radii ratio increased, causing a faster solidification process. [ABSTRACT FROM AUTHOR]