Homogeneous-heterogeneous Reactions Research Articles

Impact of an Induced Magnetic Field on the Stagnation-Point Flow of a Water-Based Graphene Oxide Nanoparticle over a Movable Surface with Homogeneous–Heterogeneous and Chemical Reactions

Water has attracted plenty of attention as a lubricant for manufacturing due to the fact that it is inexpensive, environmentally friendly, and efficient. Because of their outstanding mechanical capabilities, water dispensability, and range of real applications, graphene oxide (GO) materials have the potential to augment the effectiveness of water lubrication. With this encouragement, we inspect the impact of induced magnetism on the fluid flow near a stagnation point dispended with water-based GO nanoparticles caused by a movable surface with a homogeneous–heterogeneous chemical reaction. The leading equations and their related boundary constraints are first transformed into a non-dimensional form through the utilization of the similarity technique. The consequent equations are then numerically solved by employing the bvp4c scheme. Those figures are used to exemplify the stimulation of the relevant constraints on the fluid flow, induced magnetic profiles, temperature profiles, concentration profiles, heat transfer, and friction factor. It is observed that the nanoparticle’s volume fraction enhances the heat transfer rate, as well as the friction factor. The heat transfer and friction factor escalate by almost 11.71% and 0.96% for the respective upper-branch solutions due to the larger impacts of nanoparticles’ volume fractions, while for the lower-branch solutions, they are augmented at about 21.8% and 0.66%, respectively. In addition, double solutions can be found in the limited values of a movable parameter.

Irreversibility analysis of Reiner-Rivlin nanofluid squeezing flow amidst two rotating disks with heterogeneous catalysis

Reiner-Rivlin nanofluid flow between two disks exhibiting homogenous-heterogeneous reactions in a porous media with slip effects is appraised in this study. The envisioned unique model is supported by the surface catalyzed reaction that triggers the chemical reaction in the minimum possible time. Considering the entropy generation allows gauging the energy loss and thermal performance during the process. The similarity transformations are affianced to get the ordinary differential equations system with high nonlinearity and are handled by numerical technique bvp4c by MATLAB software. The outcomes in graphical form portraying the relationship of the protuberant factors along with associated profiles are presented. The fallouts disclosed that the disk’s torque is on the decline for high values of wall roughness. Another interesting outcome unveiled that both axial and radial velocities are weakened for the high estimates of wall roughness. To sum up the justification of the proposed model, a comparison table in a limiting case is also added.

Thermodynamics of second-grade nanofluid over a stretchable rotating porous disk subject to Hall current and cubic autocatalysis chemical reactions

Homogeneous–heterogeneous chemical reactions for second-grade nanofluid and gyrotactic microorganisms in a rotating system with the effects of magnetic fields and thermal radiation are examined. The boundary layer equations of the problem in a non-dimensional form are evaluated by a strong technique, namely, the homotopy analysis method (HAM). The rates of flow, heat, mass, and gyrotactic microorganism motion are obtained for the augmentations in the pertinent parameters. The graphical pictures of the results are described by the physical significance. The Hall current effect decreases the azimuthal velocity, the axial velocity increases with the injection of mass, the Biot number leads to enhanced heat transfer and gyrotactic microorganisms, the concentration diffusion rate decreases with the Peclet number, and the concentration of the chemical reaction reduces with the Schmidt number. Excellent agreement of the present work is found with the previously published work. The present study has applications in the hydromagnetic lubrication, semiconductor crystal growth control, austrophysical plasmas, magnetic storage disks, computer storage devices, care and maintenance of turbine engines, aeronautical, mechanical, and architectural engineering, metallurgy, polymer industry, hydromagnetic flows in porous media, and food processing and preservation processes.

A semi-analytical passive strategy to examine the water-ethylene glycol (50:50)-based hybrid nanofluid flow over a spinning disk with homogeneous–heterogeneous reactions

Scientists and researchers are much interested in studying graphene and silver nanoparticles for the enhancement of heat transport due to their extensive variety of applications in different areas of industrial and engineering such as drug delivery, medical devices, ultra-light, excellent electrical conductivity, strong medical strength, health care, consumer, food, etc. Therefore, in the existing investigation, the MHD flow of a mixed convective hybrid nanoliquid with graphene and silver nanoparticles past a rotating disk is considered. Water and ethylene glycol (50:50) is used as a base liquid in the existing model. The mechanism for heat transport is computed with the existence of thermal radiation and thermal convective condition. Homogeneous and heterogeneous chemical reactions are assumed in the flow behavior. The mathematical formulation of the proposed problem is based on the nonlinear PDEs which are then transformed to nonlinear ODEs by manipulating the appropriate similarity transformation. The simulation of the existing problem has been performed with the help of the homotopy analysis technique. The outcomes of the different flow parameters on the velocities, temperature, concentration, skin friction coefficient, and Nusselt number of the hybrid nanofluid are attained via graphs and tables. Some significant results from the existing problem demonstrate that the rate of heat transport is greater for the thermal Biot number and nanoparticles volume fraction. Further, it is noticed that the velocity of the liquid particles becomes lower for a higher magnetic field parameter.

Homogeneous-heterogeneous chemical reactions and effectiveness of thermo-sloutal time’s relaxation concept in Carreau fluid flow

This study includes Carreau fluid flow at a stagnation point under MHD influence. The Christov-Cattaneo double diffusion formula is to manipulate the heat and mass flux rate with the generation of heat. The flow is manifested by the stretched sheet. The heterogeneous-homogeneous reactions are carried out. The admissible transformations are invoked to alter the flow narrating coupled partial differential framework into a coupled ordinary differential framework. These equations are sorted out in a numerical framework with the aid of the Runge–Kutta Fehlberg technique supported by the shooting scheme. The parameter of thermal and concentration relaxation diminishes fluid temperature and concentration, respectively. The numerical results for the drag force are examined.

Aspects of Homogeneous Heterogeneous Reactions for Nanofluid Flow Over a Riga Surface in the Presence of Viscous Dissipation

The aim of our study is to delineate the characteristics of fluid flow comprising single-wall and multi-wall carbon nanotubes (SWCNTs and MWCNTs) along the surface of a Riga plate fixed in a porous environment. We carried out in-depth comparative analysis to depict the behavior of SWCNTs and MWCNTs when water and kerosene oil are used as base fluids. Homogeneous–heterogeneous reactions generated a significant impact on flow dynamics; furthermore, we also discuss the impact of viscous dissipation. We assembled numerical solutions for non-dimensionalized ordinary differential equations with the help of the shooting technique; moreover, by employing the same procedure, we report the conduct of dominating parameters on velocity, temperature, and concentration profiles. The results show highly desirable skin friction coefficient and Nusselt number values, which we exhibit in terms of tabular data.

Numerical appraisal of Yamada–Ota hybrid nanofluid flow over a cylindrical surface and a sheet with surface-catalyzed reaction using Keller box approximations

Hybrid nanofluids (HNF) are the advanced form of nanofluids used for improved heat transfer purposes. Taking this point in mind, the objective of the presented endeavor is to examine the Yamada–Ota HNF flow model comprising (gold–silver/engine oil) over a stretched cylindrical surface and a sheet (as a limiting case) in a permeable medium. The novelty of this research is the consideration of the surface-catalyzed reaction along with the homogeneous–heterogeneous reactions to accelerate the chemical reactions in the shortest possible time. The heat transport phenomenon is strengthened with the support of Joule heating, heat absorption/generation, and the convective heat boundary condition at the surface of the cylinder. The obtained ordinary differential equations are reduced from the partial differential equations using boundary layer theory and are numerically computed using the Keller box method. It is witnessed that for varied estimates of the magnetic parameter, the thermal profile enhances while the velocity field reduces. It is also noted that the fluid concentration is reduced when the surface-catalyzed parameter is enhanced. The validation of the envisioned model in a limiting case is also added to this investigation.

Enhanced thermal effectiveness for electroosmosis modulated peristaltic flow of modified hybrid nanofluid with chemical reactions

In this analysis, the thermal and flow properties of modified hybrid nanofluids (MNFs) have been investigated under the effects of electroosmosis and homogeneous-heterogeneous chemical reactions. Three types of nanoparticles of Cu, CuO, and Al2O3 are utilized to monitor the performance of the MNFs with water as a working liquid. The determination of the heating phenomenon is explored by incorporating the effects of NPs shape, temperature reliant viscosity, Joule heating, heat generation/absorption and viscous dissipation. In this exploration, equal diffusion factors for the auto catalyst and reactants are assumed. The model formulation contains a highly non-linear PDE system, which is converted to ODEs under physical assumptions with lubrication and Debye–Huckel. The solution treatment involves the Homotopy perturbation method for solving the governing differential equations is used. A major outcome discloses that an addition in heterogeneous reaction parameter aids in enhancing the concentration profile. In a result, the temperature curve decreases at increasing volume fraction of the NPs. Modified hybrid NFs have higher heat transfer rate as compared to base H20, or ordinary Al2O3–H20 and hybrid Cu + Al2O3–H20 NFs. Pressure gradient decreases by improving electroosmotic parameter. Further a comparison between analytically (HPM) and numerical results (NDSolve) show that both results are in good agreement.

Impact of surface catalyst and variable diffusion coefficients on a comparative appraisal of hybrid and nanofluid flows

A comparison of the hybrid and nanofluid flows performance amidst two spinning disks accompanying variable thermal conductivity and viscosity is appraised in this study. The hybrid nanofluid is comprised of single-wall-multiwall carbon nanotubes/water combination and a simple nanofluid consists of single-wall carbon nanotubes (multiwall carbon nanotubes)/water amalgamation. The selection of carbon nanotubes is based on their matchless characteristics including lightweight, extraordinary thermal conductivity attributes, and stability. The envisaged model is supported with catalysis on the surface to influence the homogeneous-heterogeneous reactions and trigger the process in a relatively lesser time. The cases of clockwise and anticlockwise rotation for both disks are undertaken. The numerical MATLAB-based bvp4c technique is betrothed. The graphical illustrations depicting the association of the prominent parameters with the allied profiles are given with logical arguments. The fallouts revealed that the hybrid nanofluids are more effective than the simple nanofluids as far as thermal efficiency is concerned. It is also heeded that the rate of mass transfer is proliferated for the surface catalyzed parameter. A comparison table in a limiting case is also supplemented to jazz up the justification of the presented model.

Homogeneous–Heterogeneous Reactions Within Magnetic Sisko Nanofluid Flow Through Stretching Sheet Due to Convective Conditions Using Buongiorno’s Model

The flow due to stretching sheet has key role in many engineering fields such as making rubber sheets and plastic, wire drawing, glass-fiber manufacture and hot rolling etc. The Sisko fluid has its significant role in drilling fluids, blood, cement slurry, liquid polymers, paint and mud, synovial fluid and water-borne coating. Here, we examined the magnetic Sisko fluid flow via stretching sheet with convective conditions using Buongiorno’s model and flow problem occurring due to homogeneous–heterogeneous reactions. Influence of pertinent flow parameters viz. magnetic field, material index, Brownian motion parameter, thermophoresis parameter, Brownian diffusivity, Lewis number, ratio of diffusion coefficient, strength of homogeneous reaction, strength of heterogeneous reaction and Biot number are revealed by graphs for both shear thinning (n < 1) and shear thickening (n > 1) cases. The existing model has considered the case of unequal diffusion coefficients of chemical species. Hence, accounting the interaction of both homogeneous–heterogeneous reactions. One of the important outcomes of this work is concentration of auto-catalyst of Sisko fluid decreased due to rise in material index parameter.

Radiative and Darcy-Forchheimer hybrid nanofluid flow over an inclined stretching surface due to nonlinear convection and homogeneous heterogeneous reactions

ABSTRACT The investigation to improve renewable energy resources is the main target of many scientists in the current decade. The current research aims to inspect the new theory of tri-hybrid nanofluids called ternary hybrid nanofluid flow over an inclined plate with nonlinear convection. The flat plate geometry is widely used in solar panels. The three types of nanoparticles (CuO, MgO, and Multy walled carbon nanotubes MWCNTs) are uniformly dispersed in the base fluid of water with different thermophysical and chemical properties. The homogenous and heterogeneous reactions are also countered in the flowing outline. The flow medium is considered porous including the Darcy-Forchheimer theory. The equations that govern the motion, energy and homogeneous heterogeneous reactions of the ternary hybrid nanofluid are treated with the similarity transformation. The transformed equations are solved through the semi-numerical method called the homotopy analysis method (HAM). The comparative analysis of the single, double, and triple nanoparticles are examined and the % enhancement in the heat transfer rate is calculated. The outcomes of the obtained results illustrate that the ternary hybrid nanofluids are more effective to improve the heat transfer rate as associated with the common fluids.

Melting heat transfer phenomena on Maxwell nanofluid flow with homogeneous-heterogeneous reactions: a thermophysical properties of nanoparticle aggregation approach

Melting heat transfer phenomena on Maxwell nanofluid flow with homogeneous-heterogeneous reactions: a thermophysical properties of nanoparticle aggregation approach

Influence of Inclined Magnetic Field on Peristaltic Flow of Ag–Cu/Blood Hybrid Nanofluid in the Presence of Homogeneous–Heterogeneous Reactions with Slip Condition

Influence of Inclined Magnetic Field on Peristaltic Flow of Ag–Cu/Blood Hybrid Nanofluid in the Presence of Homogeneous–Heterogeneous Reactions with Slip Condition

A New Fourth-Order Predictor–Corrector Numerical Scheme for Heat Transfer by Darcy–Forchheimer Flow of Micropolar Fluid with Homogeneous–Heterogeneous Reactions

This paper proposes a numerical scheme for solving linear and nonlinear differential equations obtained from the mathematical modeling of a flow phenomenon. The scheme is constructed on two grid points. It is a two-stage, or predictor–corrector type, scheme whose first stage (the predictor stage) comprises a forward Euler scheme. The stability region of the proposed scheme is larger than that of the first-order forward Euler scheme. A problem is constructed, comprised of a mathematical model for the Darcy–Forchheimer flow of micropolar fluid over a stretching sheet, and is modified using partial differential equations (PDEs) by incorporating the effects of homogeneous–heterogeneous reactions. A set of PDEs is further reduced into ordinary differential equations (ODEs) by several transformations and is solved using the proposed numerical scheme. By comparing the results obtained using the proposed scheme with those obtained using the existing forward Euler scheme, it can be observed that the proposed scheme achieved a smaller absolute error. The obtained results show that the angular velocity profile displayed dual behavior according to increases in the values of the microrotation and coupling constant parameters. As part of our research, we conducted a comparison with other existing schemes. The findings of this study can serve as a helpful guide for future investigations into fluid flow in closed-off industrial settings.

Entropy generation on unsteady stagnation‐point Casson nanofluid flow past a stretching sheet in a porous medium under the influence of an inclined magnetic field with homogeneous and heterogeneous reactions

AbstractThis study explores the entropy generation analysis on unsteady nonlinear radiative ethylene glycol‐based Casson nanofluid flow near stagnation point towards a stretching sheet through a porous medium. Analysis has been accomplished in the presence of an inclined magnetic field, heat generation, homogeneous–heterogeneous reactions, and viscous dissipation with velocity slip and convective boundary conditions. The nondimensional governing equations are solved by the shooting technique with the help of the RK45 method. We have experimented with copper and silver nanoparticles and a comparative analysis has been highlighted for both copper and silver nanofluids. Numerical outcomes are executed by the MATLAB built‐in bvp4c function. The consequences of the experiment for various pertinent flow parameters are portrayed by graphs and tables for both the Ag‐ and Cu‐Casson nanofluids. Results reveal that the enhancement of nanoparticles volume fraction accelerates temperature but it slows down concentration and velocity distributions. Higher values of the Eckert number boost velocity and temperature but reduce skin friction coefficient and Nusselt number. Enhancement of the Brinkman number boosts up entropy generation but it slows down Bejan's number. The results of the model can be applied in the movement of biological fluids, separation of biomolecules, glass manufacturing, paper production, food processing, crude oil purification, polymer drag reduction, and cooling atomic reactors.

Variable heat source in stagnation-point unsteady flow of magnetized Oldroyd-B fluid with cubic autocatalysis chemical reaction

Understanding the flow behavior of non-Newtonian fluids required more research in terms of various aspects. Because the role of heat transfer in non-Newtonian flows is dominant due to its importance in technology. For these benefits, a theoretical investigation is carried out to analyze the time-dependent flow of non-Newtonian fluid with a focus on thermal and solutal transport. In the present study, we formulate a mathematical model for Oldroyd-B fluid by taking into account the effect of magnetic field. The governing flow field equations are constructed with the help of the rheological expression of Oldroyd-B fluid model. For physical relevance, the effects of non-uniform heat source/sink, Joule heating and thermal radiation with homogeneous-heterogeneous chemical reactions have been incorporated in stagnation point flow towards a stretching cylinder to modify the energy and concentration distributions. The highly non-linear ordinary differential equations are tackled analytically through the optimal homotopy analysis method (OHAM). Study reveals that, the strength of homogeneous and heterogeneous reactions leads to enhanced the concentration of the catalyst at the surface. Furthermore, the non-uniform heat source/sink parameter acts like a major controlling parameter for the heat transportation rate, and heat transport is also influenced by the surface-dependent heat source/sink.

Lorentz force and Darcy-Forchheimer effects on the convective flow of non-Newtonian fluid with chemical aspects

The purpose of this study is to inspect the flow of magneto-hydrodynamic third-grade liquid through Darcy-Forchheimer’s porous space with variable features. Energy expression is explored by the convective condition and Joule heating effect. Features of homogeneous-heterogeneous reactions are accounted. Both auto-catalysts and reactants are considered equal diffusion coefficients. The incompressible liquid is conducted electrically. Proper variables convert the nonlinear flow systems to ordinary ones. Then the HAM technique is implemented for the series solution. The upshots of various variables such as the Magnetic variable, diffusion coefficient ratio parameter, Baiot number, and Prandtl number are displayed graphically. Numerical data of drag force is executed and elaborated. Our outcomes declared that temperature gradient enhances with increment in magnetic parameter and Biot number. Moreover, concentration shows a contrary trend against higher strength of homogeneous and heterogeneous reactions.

Peristaltic mechanism of Ellis fluid in curved configuration with homogeneous and heterogeneous effects

The present investigation is modeled to study the effect of homogeneous-heterogeneous reactions on MHD peristaltic mechanism of Ellis fluid in curved channel. The problem development makes use of such constitutive relations for the Ellis fluid model. The perturbation technique is referred. It is very powerful tool now a day in practically fluid mechanics and modern mathematical physics. Sequence solutions is computed by solving the resulting systems through the perturbation technique. It has been observed that the velocity profile behaves as parabolic curve that is maximum at the centerline of channel. Growing slip parameter promotes the velocity profile and maximum behavior is noticed near the centerline of the curved channel. Brinkman number and curvature parameters enhance the heat transfer distribution. Graphs are used to analyze the results of various parameters.

Dynamics of thermosolutal Marangoni convection and nanoparticle aggregation effects on Oldroyd-B nanofluid past a porous boundary with homogeneous-heterogeneous catalytic reactions

The current study is designed to analyze the thermal assessment of Oldroyd-B nanofluid past a porous boundary with a heat source/sink. The investigation is achieved by considering the nanoparticle aggregation effect. The revised model for thermal conductivity and dynamic viscosity are employed to simulate nanoliquids with the nanoparticle aggregation feature. The prospective of homogeneous-heterogeneous reactions and thermosolutal Marangoni convection is also considered. A comparative analysis is performed to verify the approximated solution. A mathematical model is developed for the flow problem with corresponding boundary constraints in terms of partial differential equations (PDEs). Later, similarity transformation is introduced to assist the investigation and to attain the reduced ordinary differential equations (ODEs). Further, using the Runge-Kutta method of order fourth fifth along with the shooting technique, the numerical calculation of this model is computed. The manuscript aims to discuss various issues that occurred for the said model. The outcome reveals that the fluid flow with nanoparticles aggregation case shows improved heat transport than for improved heat source/sink parameter values. Furthermore, for augmented values of strength of homogeneous and heterogeneous reaction parameters, the mass transfer is greater in fluid flow with aggregation conditions.

Impact of nanoparticle aggregation on heat transfer phenomena of second grade nanofluid flow over melting surface subject to homogeneous-heterogeneous reactions

It is well known that the inclusion of a certain quantity of nanoparticles boosts the thermal conductivity of the nanofluid. The reason for this tremendous improvement is yet unknown. Consequently, finding the proper thermal effect of nanoscale particles requires an understanding of nanoparticle aggregation kinematics. The utilization of nanomaterials may be seen in a variety of technological and industrial applications. The influence of homogeneous and heterogeneous chemical reactions on an incompressible flow of second-grade nanofluid through a stretched cylinder with NP aggregation is investigated in this work. Similarity transformations are used to change partial differential equations (PDEs) into a system of ordinary differential equations (ODEs). The Runge Kutta Fehlberg fourth fifth-order (RKF 45) technique and shooting approach are used to numerically solve these ODEs. The influence of major elements on flow fields and heat transfer rates is investigated and addressed using graphical representations. The results suggest that the fluid flow without NPs aggregation has better heat transmission than when the melting parameter increases. Furthermore, the higher mass transfer for fluid flow with aggregation condition is detected for increased values of strength of heterogeneous and homogeneous reaction parameters.