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1.
    
This study involvesthe numerical modeling of steady thermal radiation and chemical reaction on non-Newtonian fluid motion via a bidirectional stretching surface. We have taken convective boundary conditions, and heat sources on the stretching surface. The working fluid of the present study is Casson fluid (“non-Newtonian”) with couple stress. The self-similarity forms of the nonlinear thermal radiative flow model are obtained by using similarity variables. Furthermore, the numerical results are computed with the help of fourth-order Runge–Kutta–Fehlberg method with a shooting algorithm after reducing nonlinear partial differential equations have been translated into strong ordinary differential equations (ODEs). Impacts of the various flow physical parameters especially Biot number, nonlinear thermal radiation, and heat source parameters containing nonlinear ODEs are discussed in detail for distinct numerical values. A comparison of calculated results with the known numerical results made with the previously published literature is mentioned and obtained a good agreement. Finally, we found that the R e x 1 / 2 C f x $R{e}_{x}^{1/2}{C}_{fx}$ (“coefficient of skin friction”) declines along x * , y * $x* ,,y* $ directions, respectively, with β $beta $ via λ $lambda $ while the opposite direction follows M $M$ with respect to λ $lambda $ and the R e x 1 / 2 N u x $R{e}_{x}^{-1/2}N{u}_{x}$ (“heat transfer rate”), R e x 1 / 2 S h $R{e}_{x}^{-1/2}Sh$ (“mass transfer rate”) increase with Γ $Gamma $ via γ 1 ${gamma }_{1}$ while opposite direction follows γ 1 ${gamma }_{1}$ with respect to γ 2 ${gamma }_{2}$ .  相似文献   

2.
    
The present model concentrates on entropy generation on a steady incompressible flow of a Casson liquid past a permeable stretching curve surface through chemical reaction and magnetic field effects. The exponential space-dependent heat source cum heat and mass convective boundary conditions are accounted for. The resulting nonlinear boundary layer model is simplified by the transformation of similarity. Chebyshev spectral technique is involved for obtaining numerical results of the converted system of the mathematical models. Behavior of the determining thermo-physical parameters on the profiles of velocity, temperature, concentration, skin friction, heat, mass transfer rate, rate of entropy generation, and finally the Bejan number are presented. The major point of the present investigation show that the curvature term weakens the mass transfer profile as the fluid temperature reduces all over the diffusion regime. A decrease in heat generation strengthens the species molecular bond, which prevents free Casson particle diffusion. Furthermore, the mass transfer field diminishes in suction and injection flow medium.  相似文献   

3.
    
Microorganisms play a vital role in understanding the ecological system. The motions of micororganisms are self‐propelled while the impact of thermophoresis and Brownian motion property of nanoparticle shows more challenges in biotechnological and medical applications. The present problem is based on the understanding of double‐dispensed bioconvection for a Casson nanofluid flow over a stretching sheet. Suction phenomenon is introduced at the surface of the stretching sheet along with the convective boundary condition. The convection and movement of the microorganisms are assisted by an applied magnetic field, nonlinear thermal radiation, and first‐order chemical reaction. The governing equations are highly coupled and thus we used the spectral quasilinearization method to solve the governing equations. The study of the residual errors on the systemic parameters had given a confidence with the present results. The final outcomes are displayed through graphs and tables. The thermal dispersion coefficient shows a positive response in the temperature while a similar response is observed for the concentration with solutal dispersion coefficient. The response is reversible for the heat transfer rate at the surface with thermal dispersion coefficient. The density of the motile microorganism at the surface decreases with increase in the Casson number, thermal dispersion coefficient, and solute dispersion coefficient, while an opposite phenomenon was observed with increase in the density ratio of the motile microorganism.  相似文献   

4.
    
The aim of the current study is to explore the effects of heat and mass transfer on unsteady chemically reacted Casson liquid flow over an exponentially accelerated vertical plate in a porous medium. It is assumed that the bounding plate has varying temperatures as well as concentrations in a porous medium under a uniform magnetic field. This phenomenon is modeled in the form of a system of partial differential equations (PDEs) with boundary conditions. The governing dimensionless PDEs are solved using Laplace transform method for velocity, temperature, and concentration. The impact of nondimensional parameters, which are controlling the flow like Casson parameter, Soret number, magnetic parameter, heat generation parameter, Prandtl number, radiation parameter, and Schmidt number is analyzed through graphs. The incremental values of the Casson fluid parameter lead to a reduction in velocity and discovered that for large values of the Casson parameter, the fluid is near to the Newtonian fluid. Also, the Sherwood number increases with enhancing dissimilar estimators of the Schmidt and Soret numbers. A comparison has been made with the published work (Kataria et al.) for a particular case, which was in good agreement.  相似文献   

5.
The current study aims to study the magnetohydrodynamics (MHD) Casson kind nanofluid stream through a permeable medium above a nonlinear extending surface considered along with Darcy-Forchimer relation and chemical reaction. Thermophoresis and Brownian diffusion effects are considered. The MHD effect is used to highlight the physical and thermal properties of the nanofluid. The Keller Box scheme is used to solve the guiding equations numerically. Graphs are plotted for various nondimensional parameters. To justify the method, the used local parameters are calculated and compared with the existing literature. The results specify that a decreasing tendency is observed in the velocity profile for Forchiemer, magnetic, and stretching rate parameters, whereas the opposite tendency is noted for the Casson parameter. On observing temperature profiles, declination is noticed for Casson, thermal slip parameters and raising nature is detected for increasing values of Brownian diffusion, and thermophoresis, radiation parameters. From the results, it is observed that the momentum boundary layer diminishes for a higher inertial influence and the opposing force offered by the porous media to the fluid flow.  相似文献   

6.
    
This investigation focuses on the influence of thermal radiation on the magnetohydrodynamic flow of a Williamson nanofluid over a stretching sheet with chemical reaction. The phenomena at the stretching wall assume convective heat and mass exchange. The novelty of the present study is the thermodynamic analysis in the nonlinear convective flow of a Williamson nanofluid. The resulting set of the differential equations are solved by the homotopy analysis method. We explored the impacts of the emerging parameters on flow, heat, and mass characteristics, including the rate of entropy generation and the Bejan number through graphs, and extensive discussions are provided. The expressions for skin friction, Nusselt and the Sherwood numbers are also analyzed and explored through tables. It is concluded that the rate of mass transfer may be maximized with the variation of the Williamson and chemical reaction parameters. Moreover, the entropy generation rate and the Bejan number are augmented via increasing the Williamson parameter.  相似文献   

7.
    
The aim of the current analysis is to investigate heat and mass transfer characteristics of single and multi‐walled water‐based carbon nanotubes Maxwell nanofluid flow between continuously rotating stretchable disks under the sway of chemical reaction and radiation. Boundary conditions of the convective type of temperature are employed at both lower and upper rotating disks in the preparation. Similarity variables are employed to transform the governing partial differential equations into the nonlinear ordinary differential equations. The computational finite element method is applied to solve this nonlinear system of equations along with boundary conditions. The sway of different admissible parameters on the profiles of concentration, temperature, and velocity are inspected and revealed through graphs. Furthermore, the numerical solutions for rates of temperature, concentration, and rates of velocity are depicted in tabular form. It is revealed that temperature sketches deteriorate with augmented values of Deborah number at both upper and lower disks of single‐walled carbon nanotubes and multi‐walled carbon nanotubes with water‐based Maxwell nanofluids.  相似文献   

8.
    
Nowadays, due to the novel thermal effectiveness, a new class of fluid, named “hybrid nanofluid,” is used. It has significant applications in domestic and industrial fields. In this study, we investigated the entropy generation and heat transfer of unsteady squeezing magnetic hybrid nanofluid flow between parallel plates by considering heat source/sink and thermal radiation. In this analysis, carbon nanotubes (CNTs) (single‐walled carbon nanotube and multiwalled carbon nanotube) are considered as nanoparticles that are dispersed in water‐ethylene glycol (EG) mixtures (ie, 70%W + 30%EG and 50%W + 50%EG). For the analysis of the physical behavior of hybrid nanofluids, new models related to hybrid nanofluids are incorporated. From this study, it has been observed that as the hybrid nanofluids moved away from the surface, the entropy generation outlines accelerated with an increase in magnetic field values. Moreover, an increase in the volume fraction of CNTs, the thermal conductivity of 50%W + 50%EG + CNTs hybrid nanofluid is greater than 70%W + 30%EG + CNTs hybrid nanofluid.  相似文献   

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11.
    
We present a generalized model to describe the flow of three non‐Newtonian nanofluids, namely, Jeffrey, Maxwell, and Oldroyd‐B nanofluids. Using this model, we study entropy generation and heat transfer in laminar nanofluid boundary‐layer stagnation‐point flow. The flow is subject to an external magnetic field. The conventional energy equation is modified by the incorporation of nanoparticle Brownian motion and thermophoresis effects. A hydrodynamic slip velocity is used in the initial condition as a component of the stretching velocity. The system of nonlinear equations is solved numerically using three different methods, a spectral relaxation method, spectral quasilinearization method, and the spectral local linearization method, first to determine the most accurate of these methods, and second as a measure to validate the numerical simulations. The residual errors for each method are presented. The numerical results show that the spectral relaxation method is the most accurate of the three methods, and this method is used subsequently to solve the transport equations and thus to determine the empirical impact of the physical parameters on the fluid properties and entropy generation.  相似文献   

12.
    
Nanofluids are special functional fluids, which are designed to reduce the loss of energy and maximize the transport of heat. The thermophoresis and Brownian motion of the particle are important factors in the transport of heat in these fluids. The rise in heat transport shows encouraging effects in control of dissipation of energy and reduces entropy generation. In the current study, two-dimensional non-Newtonian Casson nanofluid flow on an upper horizontal surface of a parabola is investigated. The impact of catalytic surface chemical reactions has been account also due to its industrial importance. For this flow problem, the governing equations are modeled using the law of conservation of mass, momentum, heat, and concentration equation. The fitting transformations are taken to change governing couple partial differential equations and domain into local similar ordinary differential equation and domain of [0,∞). Using the \"RK4\" approach with Newton's shooting schemes via MATLAB tools, the numerical solution of dimensionless governing equations is sorted. It is observed that the Casson fluid parameter caused a drop in temperature profile, and the chemical reaction parameter is the source of the rise in the temperature field.  相似文献   

13.
    
In the present paper, we have discussed the thermosolutal Marangoni force acting on the electrically conducting Casson fluid flow over a permeable horizontal stretching surface. It is presumed that the condition at the interfaces is influenced by the surface tension, which is proportional to the temperature and concentration profiles. At the interface, both concentration and temperature are heated in such a way that they are quadratic functions in x . Furthermore, we have introduced the magnetic field in the transverse direction of the fluid flow along with heat generation/absorption, thermal radiation, viscous dissipation, and first‐order chemical effect with heat and mass flux into the present system. Similarity transformations have been used to convert the system of the nonlinear partial differential equations into a system of nonlinear ordinary differential equations (ODEs). The reduced ODEs are then solved using the MATLAB program bvp4c, which is based on the fourth‐order Runge‐Kutta and shooting method. The impact of various pertinent flow parameters on the flow field, temperature, and species concentration has been studied through graphs. To know the characteristics of shear stress, heat and mass rate near the boundary, numerical values of them are also calculated and given in the tabular form. The results show that the momentum boundary layer's thickness is getting thicker with an increase in solutal surface tension ratio, while its opposite trends have been observed in the thermal boundary layer region, this is due to the Marangoni effect. This Marangoni effect is very much important in the field of melting metals, crystal growth, welding, and electron beam.  相似文献   

14.
15.
    
This project mainly concentrates on the numerical investigation of the Hall and Ion impact on couple stress nanofluid flow through an inclined microchannel considering the hydraulic slip and convective boundary conditions in the presence of radiative heat flux. The analysis has been made via assuming that the fluid is incompressible, electrically conducting, and viscous. The parameters of couple stress, convection, and heat generation have been employed. Different water‐based nanofluids containing Cu , Ag , Cuo , Mo S 2 , A l 2 O 3 , and Ti O 2 are taken into account. To reduce the nonlinear system of ordinary differential equations, suitable nondimensional variables are applied to the governing equations. Then, this system is solved numerically utilizing the Runge‐Kutta‐Fehlberg fourth‐fifth‐order method along with the shooting technique. Maple software was employed to get numerical solutions. The results found that the fluid velocity is retarded for larger estimations of the Hall and Ion parameter. The drag force and the Nusselt number are diminished for higher estimations of the nanoparticle volume fraction and Brinkman number, respectively. Furthermore, it is noted that the nanoparticles have a maximum heat transfer rate as compared with the oxides of nanoparticles. The obtained results are compared with existing ones in a limiting case, and provide good agreement.  相似文献   

16.
    
A numerical investigation on MHD fluid flow in parabolic mode has been performed to point out its significant properties. Thermal radiation, porous medium, heat generation, chemical reaction, and thermal diffusion along with variable temperature and concentration are taken into consideration in the analysis. The novelty of the work is the inclusion of heat generation and thermal diffusion along with exponentially varying temperature and concentration. The constituent governing equations are solved by using finite difference schemes in explicit form. The fluctuations in velocity, concentration, and temperature are observed and discussed with the help of graphs as well as numerical data. Their gradients are also calculated and analyzed the flow properties by using numerical tables. The existence of heat generation, as well as viscous dissipation, creates an increment in the temperature. The gradient of heat transfer rises with the impact of Prandtl number and decay in it is examined under the existence of a source of heat and viscous dissipation.  相似文献   

17.
    
A numerical computation to analyze the heat and mass transfer mechanism of a magnetohydrodynamic radiative Casson fluid flow over a wedge in the presence of Joule heating, viscous dissipation, and chemical reaction is carried out in this study. The flow-governing partial differential equations are transformed as ordinary differential equations by relevant similarity transformations and subsequently resolved by Runge–Kutta numerical approach with a shooting technique. The characteristics of momentum, thermal, and concentration border layers due to various influencing parameters are graphically outlined and numerically computed by MATLAB software. We present comparative solutions to construe the relative outcomes of Casson fluid versus Newtonian fluid. Computational outcomes of friction factor and Nusselt and Sherwood numbers are tabulated with suitable interpretations. An increase in skin friction values is noted due to an increment in the thermal Grashof number, whereas a decrease is observed due to the chemical reaction parameter. The Casson fluid displays a superior heat transfer mechanism than the Newtonian fluid. Obtained outcomes are in good agreement with the prevailing literature in the limiting case.  相似文献   

18.
    
It is worth remarking that little is known about generalized differential quadrature analysis of three‐dimensional flow of non‐Newtonian Casson fluid in the presence of Lorentz force, thermal radiation, haphazard motion of tiny particles, thermomigration of these tiny particles due to temperature gradient, heat source, significant conversion of kinetic energy into internal energy, first‐order chemical reaction, convectively heated horizontal wall, and zero nanoparticles mass flux at the stretching surface. The revised form of Buongiorno's nanofluid model accounted for significant influences of Brownian motion and thermophoresis. The similarity solution was complemented with a powerful collocation procedure based on the generalized differential quadrature method and Newton–Raphson iterative scheme to achieve accuracy and convergent outcomes. The numerical effects disclose that the Casson nanofluid parameter slows down the axial velocities in both directions. Also, the unsteadiness parameter tends to decline generally the temperature throughout the medium and decrease particularly the concentration profile away from the stretching surface. These examinations are applicable in the field of biomechanics, polymer processing, and for characterizing the cement slurries.  相似文献   

19.
    
This paper investigated the chemically reactive radiating flow by using a two‐dimensional Darcy‐Forchheimer model with the convectively heated plate. The nonlinear thermal radiation is described by Joule heating and heat generation. Also, Darcy‐Forchheimer equation is related to porous medium flows. For the solution of equations, we used the numerical method. Further, more physical interpretation of the parameters was demonstrated with figures. It is found that an increase in the Prandtl number had a direct effect on the Nusselt number and temperature, whereas the opposite scenario was observed in the Eckert number.  相似文献   

20.
    
The present research study examines the magneto-hydrodynamic natural convection visco-elastic boundary layer of Casson fluid past a nonlinear stretching sheet with Joule and viscous dissipation effects under the influence of chemical reaction. To differentiate the visco-elastic nature of Casson fluid with Newtonian fluids, an established Casson model is considered. The present physical problem is modeled by utilizing the considered geometry. The resulting system of coupled nonlinear partial differential equations is reduced to a system of nonlinear ordinary differential equations by applying suitable similarity transformations. Numerical solutions of these reduced nondimensional governing flow field equations are obtained by applying the Runge-Kutta integration scheme with the shooting method (RK-4). The physical behavior of different control parameters is described through graphs and tables. The present study describes that the velocity and temperature profiles decreased for increasing values of Casson fluid parameter. Velocity field diminished for the increasing nonlinear parameter whereas velocity profile magnified for increasing free convection parameter. Thermal field enhanced with increasing magnetic parameter in the flow regime. The concentration profile decreased for the rising values of the chemical reaction parameter. The magnitude of the skin-friction coefficient enhanced with increasing magnetic parameter. Increasing Eckert number increases the heat transfer rate and increasing chemical reaction parameter magnifies the mass transfer rate. Finally, the similarity results presented in this article are excellently matched with previously available solutions in the literature.  相似文献   

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