Papers by Keyword: Chemical Reaction

Abstract: This study investigates the steady magnetohydrodynamic flow of the Walter-B ternary nanofluid (composed of water-ethylene glycol (WEG) base fluid with graphene, alumina, and titanium dioxide nanoparticles) over a nonlinear stretching sheet, incorporating the effects of cross-diffusion, couple stress, and viscous dissipation. Using similarity transformations, the governing equations are converted to ordinary differential equations and solved numerically with MATLAB's bvp4c solver. A Bayesian-regularized artificial neural network (BRANN) is developed to predict skin friction, Nusselt, and Sherwood numbers with R² > 0.99 accuracy. Results reveal that fluid velocity decreases with increasing couple stress but enhances with the Deborah number and Darcy parameter, while temperature rises with the Eckert and Dufour numbers. Concentration profiles decline with chemical reaction but grow with the Soret number. Entropy generation intensifies with Brinkman and Biot numbers, whereas the Bejan number shows opposite behavior. Empirical correlations for skin friction, Nusselt, and Sherwood numbers are developed, showing a 6.3% rise in skin friction with the Forchheimer number and a 13.14% improvement in heat transfer with thermal radiation. This work provides critical insights for thermal management systems, leveraging machine learning to optimize ternary nanofluid flows in porous media under cross-diffusion effects.

Abstract: The analysis of unsteady MHD flow over a porous stretching plate is critical for various engineering applications, particularly in systems involving chemical reactions and thermal radiation. This study explores the novel effects of heat and mass transfer in a two-dimensional unsteady magnetohydrodynamic (MHD) flow. This present work examines the effects of radiation and a transverse magnetic field on a chemically reacting fluid flowing over a stretched plate. The unsteady nature of the flow is associated with the time-dependent variations in stretching/extending velocity, temperature, and fluid concentration. The nonlinear governing boundary layer partial differential equations (PDEs) are transformed into a set of nonlinear ordinary differential equations (ODEs) using a similarity transformation, which are then numerically solved using the MATLAB bvp4c method. The flow, heat, and concentration profiles are quantitatively analysed through graphs for various problem parameters, including the unsteadiness parameter (A), Hartmann number (M), porosity parameter (Sp), radiation parameter (N), chemical reaction parameter (K), Soret number (Sr), Eckert number (Ec), Schmidt number (Sc), and Prandtl number (Pr). Additionally, the skin friction coefficient, Nusselt number (Nu), and Sherwood number (Sh) are numerically addressed and illustrated using graphs.

Abstract: This study examines the Magnetohydrodynamics (MHD) Casson flow passing over a non-linear convective inclined plate with incorporating a chemical reaction and Arrhenius activation energy. However, the magneto-hydrodynamic flow of two-dimensional radiative Casson fluid (CF) across a non-linear convective inclined plate in the existence of heat generation is addressed theoretically and numerically. The Arrhenius activation energy and chemical reaction are two additional impacts that have been added to the innovative nature of the model. By applying the appropriate transformations, PDEs (partial differential equations) were converted into coupled ODEs (ordinary differential equations) in terms of similarity variables combined with the boundary conditions. The finite difference method (FDM) and MAPLE 18.0 software were used to solve the resultant equations numerically. According to the findings, the thermal Grashof number and the mass Grashof number of the nano-fluid flow model were able to improve the strength of the drag coefficient, the rate of heat transfer at the surface of the plate, and the Sherwood number. Additionally, there was a reduction in the velocity gradient as the magnetic field strength increased. The concentration decreases when a chemical reaction is present, but it improves as the activation energy rises. These findings will help engineers create devices with strong heat and mass transfer rates. The results were compared to previously published research to assess their validity and discovered a large degree of consistency.

Abstract: In this work, the investigation has focused on the unsteady hydromagnetic mixed convection couple stress fluid through an inclined linearly stretching sheet. The model equations governing the flow are converted to ordinary differential equations employing appropriate similarity transformation variables. An efficient technique, Runge-Kutta 4th order (RK4) technique together with shooting method is deployed to tackle the dimensionless equations with relevant boundary conditions. The impacts of various parameters such as unsteadiness parameter , Hartman number , mixed convection parameter , concentration buoyancy parameter , angle of inclination , chemical reaction parameter and Schmidt number are analysed and discussed with plots. Fluid velocity decreases as the unsteadiness, Hartman number, Schmidt number, and chemical reaction parameters rise; while the angle of inclination, mixed convection, and concentration buoyancy parameters speed up the flow. Furthermore, the unsteadiness, angle of inclination and mixed convection parameters reduce fluid temperature, while all the parameters reduce flow concentration.

Abstract: The impact of nanoparticle shapes (i.e., blade, brick, cylindrical, platelet, and spherical) on the MHD flow of Ag-MgO/water hybrid nanofluid over a stretching/shrinking sheet is scrutinized in this study. Chemical reaction and activation energy are included in the governing partial differential equations of the flow problem. On the boundary, velocity slip and zero mass flux conditions are considered. The simplification of the governing equations and boundary conditions into non-linear ordinary differential equations is done through similarity transformation. Then, the bvp4c solver in Matlab is deployed for computation, with the results generated in the form of numerical solutions and graphs. It is found that the usage of spherical-shaped nanoparticles produces the lowest magnitude of skin friction coefficient, and the implementation of blade-shaped nanoparticles in the hybrid nanofluid provides the highest enhancement of heat transfer rate. The increment in activation energy slows down the chemical reaction that raises the concentration profile of the hybrid nanofluid. However, the concentration profile decreases as the reaction rate increases.

Abstract: This paper deals with natural thermal convection combined with the mass transfer of nanoparticles occurring in the boundary layers of a nanofluid subjected to magnetohydrodynamics. The wall consists of an inclined plate is considered according to a temperature as well as the volume fraction of the nanoparticles varying as the power of the axial coordinate. In addition, internal heat generation/absorption is taken into account in the mathematical formulation. The governing partial differential equations based on Buongiorno's approach are transformed into a set of ordinary differential equations. The two-level method of no-similarity equations is used to achieve higher accuracy. The whole calculation procedure is implemented using a limit value problem program written according to the Matlab computer language that applies the Lobbato IIIa finite difference method. The obtained results have revealed that small variations of the boundary conditions with the axial coordinate become very significant on the local Nusselt number and the local Sherwood number for nanoparticles. Moreover, a better heat transfer has been obtained with a larger S. However, a trade-off between desired heat transfer rate and level of reduced skin friction should be scheduled.

Abstract: This paper examined the thermophoresis effect and suction/injection process on steady MHD in a semi-infinite inclined porous plate. Chemical reaction, heat generation and thermal radiation are taking into account. The governing partial differential equations are transformed via similarity technique into a system of nonlinear ordinary differential similarity equations, which are solved numerically by applying the Lobbato IIIa-finite-difference method. Favorable comparisons with previously published work are performed. Numerical pertinent results for the velocity, temperature and concentration profiles as well as for the skin-friction coefficient, wall heat transfer and mass transfer rates are obtained and reported graphically for various parametric conditions to show interesting aspects of the solution. The main results are the dominant influence of suction/injection process to control the principal boundary layers and the role played by the combined chemical reaction, heat generation and thermal radiation on the changes in the quantities of interest.

Abstract: This article investigates the combined effect of second-order velocity slip, Arrhenius activation energy and binary chemical reaction on reactive Casson nanofluid flow in a non-Darcian porous medium. The governing equations of the problem were first non-dimensionalized and later reduced to ordinary nonlinear differential equations by adopting a similarity transformation. The emerging nonlinear boundary value problem was solved by using Galerkin weighted residual method (GWRM). The obtained results were compared with those found in the literature to validate our method. The impact of pertinent parameters on the velocity component, temperature distribution and concentration profile are presented using graphs and were discussed. The computational results show that an increase in second order slip parameter significantly results to an increase in the temperature as well as nanoparticle concentration profiles, while it reduces the velocity profile.

Abstract: This paper studies the effects of heat generation and chemical reaction on the coupled conjugate heat and mass transfer by MHD laminar mixed convective flow along a vertical slender hollow cylinder. The governing boundary layer equations along with the boundary conditions are first cast into a dimensionless form by a non similar transformation and the resulting equations are then solved by the finite difference method using Matlab^@ following the code bvp4c. Numerical results of the velocity, temperature and concentration for different values of the conjugate heat transfer parameter p, the magnetic parameter M, the heat generation Q, and the chemical reaction K are studied. The local skin friction, Nusselt number and Sherwood number are also analyzed and presented graphically. In the numerical ranges of the main parameters, it is found mainly that working with strong conjugate heat transfer or/and all others parameters affects negatively the Nusselt and Sherwood numbers. The same trend is revealed for the skin friction factor.

Abstract: The influence of Casson nanofluid's participating parameters over a stretched sheet is explored numerically. The fluid momentum equations are transformed to ODEs with suitable dimensional less parameters. Runge-Kutta method of fourth order method is applied. The impact on fields of velocity, temperature and concentration of magnetic, Casson porosity, radiation, Prandtl, Brownian and thermophoresis parameters and chemical reaction parameters are graphically illustrated and discussed qualitatively.