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This paper evaluates thermal output for the flow of Maxwell nanofluid over an extending sheet with bioconvection of micron size self‐motivated organisms. Radiative heat flux and two temperature boundary conditions, namely, prescribed surface temperature (PST) and prescribed heat flux (PHF), are considered. The flow is influenced by a magnetic field and porosity effects of a medium. The motivation pertains to attain an enhancement in thermal transportation via nanoparticle inclusion. The possible settling of the nanoparticles may be avoided by bioconvection of microorganisms. The basic theoretical conservation of mass, concentration, momentum, and energy provides a nonlinear set of partial differential equations which are then transmuted into ordinary differential form. The implementation of Runge–Kutta method with shooting technique in Matlab coding resulted the numerical solution. A deep insight into the problem is inspected by varying the inputs of influential parameters of the dependent functions. It is perceived that the flow speed is hindered by the growing inputs of parameters of buoyancy ratio, magnetic field, Raleigh number, and porosity. The temperature of the fluid attains higher outputs directly with thermophoresis and Brownian movement of nanoparticles. Motile microorganisms χ(η) profile goes down when bioconvection Schmidt number intensified. The current numeric results are validated when compared within existing studies. [ABSTRACT FROM AUTHOR]

In this paper, an investigation into Williamson nanofluid stagnation point flow of nano-biofilm over a stretching/ shrinking sheet with chemical reaction is performed. Moreover, the impact of cylindrical-shaped nanoparticles, activation energy, and bioconvection has been considered. The fluid's fluctuating transport properties (dynamic viscosity, heat conductivity, nanoparticle mass diffusivity) and microorganism diffusivity are evaluated. The nonlinear systems of partial differential equations are transformed into nonlinear differential equations via the implementation of similarity transformations. The shooting approach and RK-4 technique are used for this investigation. The impacts of various fluid transport characteristics and various factors on patterns of velocity, temperature, the concentration of nanoparticles, and motile density are described. The Brownian motion, heat source and thermophoresis parameters all lead to a more consistent temperature profile being observed. It is seen that concentration-dependent properties decrease the velocity profile while the temperature, concentration, and motile density profiles increase. Also, the physical quantities decrease with the rising values of concentration-dependent properties. [ABSTRACT FROM AUTHOR]

Numerical investigation for enhancement in thermal distribution of unsteady dynamics of Williamson nanofluids and ordinary nanofluids flow across extending surface of a rotating cone is represented in this communication. Bio-convection of gyrotactic micro-organisms and thermal radiative fluxes with magnetic fields are significant physical aspects of the study. The velocity slip conditions are considered along x and y directions. The leading formulation is transmuted into ordinary differential form via similarity functions. Five coupled equations with non-linear terms are resolved numerically through the utilization of Matlab code for the Runge–Kutta procedure. The parameters of buoyancy ratio and bio-convection Rayleigh number decrease the x-direction velocity. The slip parameter being proportional to viscosity reduces the speed of flow and hence rise in temperature. Also, the temperature rises with the rising values of magnetic field strength, radiative heat transportation, Brownian motion and thermophorsis. [ABSTRACT FROM AUTHOR]

The purpose and novelty of our study include the scrutinization of the unsteady flow and heat characteristics of the unsteady Sutterby nano-fluid flow across an elongated cone using slip boundary conditions. The bioconvection of gyrotactic micro-organisms, Cattaneo–Christov, and thermal radiative fluxes with magnetic fields are significant physical aspects of the study. Anisotropic constraints on the cone surface are taken into account. The leading formulation is transmuted into ordinary differential formate via similarity functions. Five coupled equations with nonlinear terms are resolved numerically through the utilization of a MATLAB code for the Runge–Kutta procedure. The parameters of buoyancy ratio, the porosity of medium, and bioconvection Rayleigh number decrease x-direction velocity. The slip parameter retard y-direction velocity. The temperature for Sutterby fluids is at a hotter level, but its velocity is vividly slower compared to those of nanofluids. The temperature profile improves directly with thermophoresis, v-velocity slip, and random motion of nanoentities. [ABSTRACT FROM AUTHOR]

The communication describes a theoretical framework for tangent hyperbolic fluid of nano-biofilm due to an extending or shrinking sheet that comprises a stagnation point flow, chemical reaction with activation energy, and bioconvection of gyrotactic microorganisms. The varying transport features due to dynamic viscosity, thermal conductivity, nano-particle mass permeability and microbe organisms diffusivity are taken into account for the novelty of this work. The inspiration is developed to enhance heat transfer. A set of leading partial differential equations is formed along with appropriate boundary constraints. Using similarity transformations, the basic formulation is transitioned into non-linear differential equations. To produce observational data, the shooting technique and Runge-Kutta fourth order method are employed. The coding of numerical scheme is developed in Matlab script. The visual representation of the effects of diverse fluid transport properties and distinctive parameters on speed, temperature, concentration and motile density are evaluated. The velocity become faster when the parameters ω , λ , ϵ and V 0 are enhanced. Brownian motion, thermal conductivity, heat generation as well as thermophoresis factors all strengthen the temperature distribution, however the nano-particle concentration profile is enhanced as the nano-particle mass conductivity variable, activation energy as well as the thermophoresis variable are boosted. The microorganism density improves significantly when the microorganism diffusivity factor increases. The skin friction, Sherwood number, Nusselt number and motile density number decline against the incremented transport parameters. [ABSTRACT FROM AUTHOR]

In this article, we explore how activation energy and varied transit parameters influence the two-dimensional stagnation point motion of nano-biofilm of Sutterby fluids incorporating gyrotactic microbes across a porous straining/shrinking sheet. Prior investigations implied that fluid viscosity as well as thermal conductance are temperature based. This research proposes that fluid viscosity, heat capacity and nanofluid attributes are all modified by solute concentration. According to some empirical research, the viscosity as well as heat conductivity of nanoparticles are highly based on the concentration of nanoparticles instead of only the temperature. The shooting approach with the RK-4 technique is applied to acquire analytical results. We contrast our outcomes with those in the existing research and examine their consistency and reliability. The graphic performance of relevant factors on heat, velocity, density and motile concentration domains are depicted and discussed. The skin friction factor, Nusselt number, Sherwood number and the motile density are determined. As the concentration-dependent properties are updated, the speed, temperature, concentration and motile density profiles are enhanced, but for all concentration-varying factors, other physical quantities deteriorate. [ABSTRACT FROM AUTHOR]

The evolution of compact density heat gadgets demands effective thermal transportation. The notion of nanofluid plays active role for this requirements. A comparative account for Maxwell nanofluids and Williamson nanofluid is analyzed. The bioconvection of self motive microorganisms, non Fourier heat flux and activation energy are new aspects of this study. This article elaborates the effects of viscous dissipation, Cattaneo–Christov diffusion for Maxwell and Williamson nanofluid transportation that occurs due to porous stretching sheet. The higher order non-linear partial differential equations are solved by using similarity transformations and a new set of ordinary differential equations is formed. For numerical purpose, Runge–Kutta method with shooting technique is applied. Matlab plateform is used for computational procedure. The graphs for various profiles.i.e. velocity, temperature, concentration and concentration of motile micro-organisms are revealed for specific non-dimensional parameters. It is observed that enhancing the magnetic parameter M, the velocity of fluid decreases but opposite behavior happens for temperature, concentration and motile density profile. Also the motile density profile decrease down for Pe and Lb. The skin friction coefficient is enhanced for both the Williamson and Maxwell fluid. [ABSTRACT FROM AUTHOR]

It is a theoretical exportation for mass transpiration and thermal transportation of Casson nanofluid over an extending cylindrical surface. The Stagnation point flow through porous matrix is influenced by magnetic field of uniform strength. Appropriate similarity functions are availed to yield the transmuted system of leading differential equations. Existence for the solution of momentum equation is proved for various values of Casson parameter β , magnetic parameter M, porosity parameter K p and Reynolds number Re in two situations of mass transpiration (suction/injuction). The core interest for this study aroused to address some analytical aspects. Therefore, existence of solution is proved and uniqueness of this results is discussed with evaluation of bounds for existence of solution. Results for skin friction factor are established to attain accuracy for large injection values. Thermal and concentration profiles are delineated numerically by applying Runge-Kutta method and shooting technique. The flow speed retards against M, β and K p for both situations of mass injection and suction. The thermal boundary layer improves with Brownian and thermopherotic diffusions. [ABSTRACT FROM AUTHOR]

AbstractThe study pertains on the dynamics and thermal distribution of magnetohydrodynamics (MHD) micropolar hybrid nanofluids flowing between two parallel plates channel. It explores the enhancement of heat transport processes by blending the base fluid with nanoparticles at varying concentrations. A system of nonlinear partial differential equations is developed as governing equations for momenta and heat energy. To facilitate numerical solutions for fluid temperature and velocities, this formulation is translated into ordinary differential form using the necessary similarity transformation. By utilizing Matlab code for the Runge–Kutta method and shooting approach, we evaluate the results. It has been observed that an increase in the concentration of hybrid nanoparticles enhance the heat transmission. The salient findings of this study reveal alteration in the velocity profiles for both nanofluid (SWCNT/water) and hybrid nanofluids (SWCNT + MWCNT/water) flow. Notably, with a substantial input of magnetic field strength (M) and porosity parameters (P0), the velocity is increased near the walls but it decelerates toward the center of channel. Additionally, the temperature rises for hybrid nanofluids. Furthermore, an increase in the θw temperature ratio parameter leads to an enhanced thermal distribution. [ABSTRACT FROM AUTHOR]

In this article, we explore how activation energy and varied transit parameters influence the two-dimensional stagnation point motion of nano-biofilm of Sutterby fluids incorporating gyrotactic microbes across a porous straining/shrinking sheet. Prior investigations implied that fluid viscosity as well as thermal conductance are temperature based. This research proposes that fluid viscosity, heat capacity and nanofluid attributes are all modified by solute concentration. According to some empirical research, the viscosity as well as heat conductivity of nanoparticles are highly based on the concentration of nanoparticles instead of only the temperature. The shooting approach with the RK-4 technique is applied to acquire analytical results. We contrast our outcomes with those in the existing research and examine their consistency and reliability. The graphic performance of relevant factors on heat, velocity, density and motile concentration domains are depicted and discussed. The skin friction factor, Nusselt number, Sherwood number and the motile density are determined. As the concentration-dependent properties are updated, the speed, temperature, concentration and motile density profiles are enhanced, but for all concentration-varying factors, other physical quantities deteriorate. [ABSTRACT FROM AUTHOR]

Prime aim of current study is to explore the comparative outcomes for mass and thermal transportation of various fluids models namely Newtonian, micropolar, Williamson and Maxwell due to extending surface. This exploration is concerned to the effect of double diffusion and applied magnetic field. The bioconvection may improve the settling of nanoparticles and the double diffusion effects are considered to be more realistic on the part of this work. The mixture of base fluids with nanoparticles and gyrotactic micro-organisms is homogenous. By the implementation of basic conservation laws, the governing partial differential equations are organized which are then reformed into corresponding ordinary differential equations. For the physical insight, Runga-Kutta method with shooting technique is utilized. The controlling parameters of buoyancy ratio, thermophoresis, magnetic field, Brownian movement, Lewis number and Prandtl number are varied in acceptable ranges to evaluate their impacts on temperature, momentum, concentration field and micro-organisms concentration. The notable outcomes indicated that micropolar fluid takes the highest value for velocity and then Newtonian fluid, Williamson fluid and Maxwell fluid in descending order. The results related to different three non-Newtonian nano-fluids with effective heat transfer can find applications in heat transfer processes such as heat exchanger. [ABSTRACT FROM AUTHOR]

The main purpose of this study is to investigate the multislip effects on the magneto-hydrodynamic (MHD) mixed convection unsteady flow of micropolar nano-fluids over a stretching/shrinking sheet along with radiation in the presence of a heat source. The consequences of multislip and buoyancy conditions have been integrated. By using the suitable similarity variables are used to solve the governing non-linear partial differential equations into a system of coupled non-linear ordinary differential equations. The transformed equations are solved numerically by using Runge–Kutta fourth-order method with shooting technique. The impacts of the several parameters on the velocity, temperature, micro-rotation, and concentration profiles as well as on the skin friction coefficient, Sherwood number, and Nusselt number are discussed with the help of graphs and tables. [ABSTRACT FROM AUTHOR]

In the past few years, many technical strategies, such as molding, condenser heat exchanger, liquefied metal filtration, fusion control and nuclear reactor coolant, that involve hydromagnetic fluxes and thermal intensification in porous media have been observed. This study investigates the Carreau nanofluid of nanobiofilm through stretching/shrinking sheet with a stagnant point flow, nanoparticles and convecting microbes. The orthogonal (9 0 ∘ impinge) coating stagnant point circulation of a medium is considered, although the sheet may be stretched/shrinked as the procedure utilized in industry. The variations in the fluid (dynamic viscosity, thermal conductivity, mass permeability) and microbes are utilized. The similarity transformation factors are used to transform the system of partial differential equations into a nonlinear system of ordinary differential equations. To find the solution of a system of equations, the Runge–Kutta method with shooting technique has been used. The flow rate, temperature and concentration, as well as the heat transfer rate, and the physical quantities have been discussed. The nanoparticle volume fraction increases with the increasing effect of activating energy as well as thermophoresis parameter, but it decreases with the enhancing effect of Lewis number (Le) and Brownian motion parameter (Nb). The graphs and tables display the illustration of the influence of different parameters. [ABSTRACT FROM AUTHOR]

In this study, the impact of activation energy and transiting parameters on the two-dimensional stagnation point flow of magnetized Sutterby nanofluid of nano-biofilm incorporating with microorganisms over the porous surface has been examined. Prior research suggests that both the fluid viscosity and thermal conductance are temperature-dependent. Also, the effects of solutal concentration on fluid viscosity, heat capacity and nanofluid properties have been elaborated. In recent years, numerous technical strategies comprising hydromagnetic fluxes and thermal intensification in porosity media, like molding, condenser heat exchanger, liquefied metal filtration, fusion control and nuclear reactor coolant, have been addressed. According to numerous empirical studies, the viscosity and thermal conductivity of the nanoparticles are largely dependent on the intensity of nanoparticles rather than the temperature. The classical RK-4 method with shooting technique has been used. The significance of involving parameters in the domains of heat, velocity, density and concentration has been illustrated. The effect of nondimensional parameters on the skin friction factor, Nusselt number and Sherwood number has been discussed. The nanoparticle density increases with the activating energy effects and thermophoresis factor and rapidly decreases for Lewis number and Brownian factor. The velocity, temperature and concentration profiles increase as the concentration-dependent properties do, but all physical quantities deteriorate for all concentration-varying factors. [ABSTRACT FROM AUTHOR]

The main objective of this investigation is to reveal the effects of nanoparticle aggregation aligned to thermal radiation with the prescribed heat flux. The Cattaneo–Christov heat flux (non-Fourier) and mass flux (non-Fick's) approaches in the optimized Buongiorno's model have been used to analyze the nanofluid magneto-transport mechanisms over the surface impacted by the gyrotactic behavior of microbe dispersion. The partial differentials are transformed into the set of nonlinear differential equations through boundary layer estimations and similarity substitutions, then computed by applying a variational finite element strategy. Researchers are looking into tiny nanoparticles because they have amazing properties, such as excellent thermal conduction, which are needed in advanced nanotechnology, heat exchangers, materials engineering, and technologies. The significance of this extensive study is to enhance the heat transition. Various aspects of the aggregation parameters on nanofluid velocity and temperature patterns are investigated and visually illustrated concerning the involved physical parameters. The effect of nanoparticle aggregation on the boundary is descending by the including parameters causes an increment in heat transfer rate. A significant correlation has been observed between the sets of results, which represents the accuracy of the finite element method used herein. The computations have been done by reducing the size of the mesh so that the numerical analysis can be used to ascertain convergence in the results. [ABSTRACT FROM AUTHOR]

This presented work investigate the bio-convections effects of the magnetized time dependent axisymmetric flow of Carreau-nanomaterial performances with multiple slip effects over a stretching sheet. The momentum, heat, concentration and density of motile micro-organism are renovated into the system of equation via using well known similarity revolution. Well known Mathematical computational techniques and software (i.e. bvp4c and MATLAB) are used to draw graphical and tabular results. Velocity profile equation f ′ (ζ) , energy equation θ (ζ) , volumetric nanoparticles ϕ (ζ) , density motile microorganism χ (ζ) .The Carreau viscosity model is use to reduce the viscosity of fluid when W e = 0 and n = 0 . Besides we moderate this into power law index with n = 0.5 and n = 1.5 partial slip condition of velocity is also instigated at the surface. Gravity dependent gyrotactic nanoparticles are utilized for well observing axisymmetric flow with convective boundary layer condition and comparatively better heat transfer rate result and applicable to maximum realistic approach. [ABSTRACT FROM AUTHOR]

The main objective of this investigation to examine the momentum and thermal transportation of rotating dusty micropolar fluid flux with suspension of conducting dust particles across the stretched sheet. The novelty of the flow model is the exploration of the significance of boosting the volume concentration of dust particles in fluid dynamics. The governing PDEs of the problem for both phase models are transmuted into nonlinear coupled non-dimensional ODEs by utilizing suitable similarity modifications. The bvp4c technique was utilized in MATLAB script to acquire a graphical representation of the experimental results. This study illustrates the analysis of repercussions of pertinent parameters on non-Newtonian fluid and the dusty phase of fluid. By improving the volume concentration of dust particles and rotating parameters, the axial velocity for both phases depreciates, whereas temperature and transverse velocity for both phases have the opposite behavior. The micro-rotation distribution rises with higher contributions of rotating and material parameters, whereas it decreases against larger inputs of volume concentration of dust particles. The growing strength of the dust volume fraction ( ϕ d ) caused the coefficient of skin friction to decrease along the x direction, and the skin friction coefficient is raised along the y direction. [ABSTRACT FROM AUTHOR]

This study addresses thermal transportation associated with dissipated flow of a Maxwell Sutterby nanofluid caused by an elongating surface. The fluid passes across Darcy–Forchheimer sponge medium and it is affected by electromagnetic field applied along the normal surface. Appropriate similarity transforms are employed to convert the controlling partial differential equations into ordinary differential form, which are then resolved numerically with implementation of Runge–Kutta method and shooting approach. The computational analysis for physical insight is attempted for varying inputs of pertinent parameters. The output revealed that the velocity of fluid for shear thickening is slower than that of shear thinning. The fluid temperature increases directly with Eckert number, and parameters of Cattaneo–Christov diffusion, radiation, electric field, magnetic field, Brownian motion and thermophoresis. The Nusselt number explicitly elevated as the values of radiation and Hartmann number, as well as Brownian motion, improved. The nanoparticle volume fraction diminishes against Prandtl number and Lewis number. [ABSTRACT FROM AUTHOR]

• Unsteady rotating flow of nanofluid persuaded by Cattaneo–Christov diffusion is modeled. • Buongiorno model for nanoparticles is taken into account for modeling. • Variational finite element technique is implemented to solve the non-linear systems of partial differential equations. • Chemical reaction with novel aspect of activation energy is accounted. • Skin friction attains higher values for variable viscosity flow than that for constant viscosity flow. This article addressees the dynamics of fluid conveying tinny particles and Coriolis force effects on transient rotational flow toward a continuously stretching sheet. Tiny particles are considered due to their unusual characteristics like extraordinary thermal conductivity, which are significant in advanced nanotechnology, heat exchangers, material sciences, and electronics. The main objective of this comprehensive study is the enhancement of heat transportation. The governing equations in three dimensional form are transmuted in to dimensionless two-dimensional form with implementation of suitable scaling transformations. The variational finite element procedure is harnessed and coded in Matlab script to obtain numerical solution of the coupled non-linear partial differential problem. It is observed that higher inputs of the parameters for magnetic force and rotational fluid cause to slow the primary as well as secondary velocities, but the thermophoresis and Brownian motion raise the temperature. However, thermal relaxation parameter reduces the nanofluid temperature. The velocities for viscosity constant case are faster than that for the variable viscosity, but temperature and species concentration depict opposite behavior. [ABSTRACT FROM AUTHOR]

The correlation coefficient between two variables plays an essential part in statistics. In addition, the preciseness in the assessment of correlation relies on information from the set of discourse. The data collected for various statistical studies is full of ambiguities. In this article, we investigated some fundamental concepts that strengthen the current research structure, such as soft sets, hypersoft sets, neutrosophic hypersoft set (NHSS), and interval-valued neutrosophic hypersoft set (IVNHSS). The IVNHSS is an extension of the interval-valued neutrosophic soft set. The main objective of this paper is to develop the concept of correlation and weighted correlation coefficients for IVNHSS. We also, discuss the desirable properties of correlation and weighted correlation coefficients under the IVNHSS environment in the following research. Also, develop a decisionmaking technique based on the proposed correlation coefficient. Through the developed methodology, a technique for solving decision-making concerns is planned. Moreover, an application of the projected methods is presented for the selection of a medical superintendent in a public hospital. [ABSTRACT FROM AUTHOR]

The enhancement of thermal conductivity of base fluids is desirable with the inclusion of nano-entities and bioconvection of microorganisms. The influence of the multi-slips on magnetohydrodynamic bio-convection streamline of micropolar based nanofluid across a sponge medium owing to expanding sheet is investigated in this work. The mass transpiration and activation energy with Fourier-Fick diffusion is taken into account. The leading partial differential equations are transformed into ordinary differential equations by using similarity transformations. The graphs were created by using the RK-4th order method with the shooting technique. Nusselt number, Sherwood number, skin friction factor, and motile density function are enumerated and analyzed with the variance of influenced parameters. It is observed the magnitude of the skin friction factor is enhanced with higher inputs of magnetic field and porosity parameters. Also observed that fluid speed is higher for injection than that of suction. [ABSTRACT FROM AUTHOR]

This investigation, scrutinizes the effects of Stephen blowing on Prandtl nanofluids transportation caused by a stretch in the sheet. The fluid temperature, thermal conductivity due to dispersion of nanoparticles with enhanced is investigated. Cartesian coordinates are used for flow equations. The similarity variables for momentum, temperature and concentration profiles, are utilized to modify the perceptions of governing flow. Nonlinear ODEs are gained from the governing PDEs and cracked down numerically by shooting and Keller box approach. The graphical and numerical sections are viewing the results for the velocity temperature and concentration fields against the independent parameters and non-dimensional numbers. As the boosting the values of material parameters α and β move opposite on velocity profile f ′(η) but similar effects of Nt and Nb are observed on both temperature and concentration profiles. The skin friction − f ″(0)is profitable unhappy at the increase values of the Hartman number with the fluctuations in the value of Stephen blowing.(S = − 1, 0, 1). The conflicting behavior of Prandtl and Eckert numbers are detected on temperature profile. Physical explanation of the graphical segment is support to understand the performance of fluids flow. [ABSTRACT FROM AUTHOR]

The present work examines the effect of different magnetic nanoparticles and the heat transfer phenomena over the stretching sheet with thermal stratification and slips effect. The mixture of water (H 2 O) and ethylene glycol (C 2 H 6 O 2 ) is used as base fluid whereas the paramagnetic, diamagnetic, and ferromagnetic ferrites are taken as nanoparticles. In the presence of ferrite nanoparticles, the magnetic dipole has a significant effect in controlling the rate of heat transfer and the thermal boundary layers. By using suitable similarity transformations, the system of partial differential equations is transformed into nonlinear ordinary differential equations. The numerical solution of resulting equations is found out by using the variational finite element method. The effect of numerous emerging parameters on velocity, temperature, and micro-rotation velocity are represented graphically and analyzed numerically. It has been noticed that comparatively the diamagnetic ferrites have gained maximum thermal conductivity relative to the other nanoparticles. It was also observed that the thermal conduction of nanoparticles increases with the variation of volume fraction. Moreover, with increasing values of thermal stratification the thermal boundary layer thickness decreases and the heat transfer rate increases at the surface. Furthermore, the validation of code and the accuracy of the numerical technique has been confirmed by the assessment of current results with earlier studies. [ABSTRACT FROM AUTHOR]

The present study investigated the unsteady magnetohydrodynamic (MHD) nanofluid flow over a radially nonlinear stretching sheet along with the viscosity dependent on temperature, convective boundary condition, thermo-diffusion, and the radiation effects. Moreover, the nanofluid's viscous effects were considered dependent on temperature and the exponential Reynolds model was considered in this context. It was additionally assumed that a uniform suspension of nanoparticles is present in the base fluid. The Buongiorno model, which involves the thermophoresis and Brownian motion effects, was considered. For the sake of a solution, the variational finite element method was selected with coding in MATLAB and the numerical results were contrasted with the published articles. The influence of various physical parameters on the velocity, temperature, and concentration profiles are discussed by the aid of graphs and tables. It was detected that the nanofuid viscosity parameter declines the fluid flow velocity, while, for the temperature and the concentration profiles, it accomplished the reverse phenomenon. [ABSTRACT FROM AUTHOR]