Influence Of Activation Energy Research Articles

Irreversible and reversible chemical reaction impacts on convective Maxwell fluid flow over a porous media with activation energy

The Maxwell model of fluid flow in a rotating frame over a porous media is investigated in this paper. Binary chemical reactions and fluid movement under activation energy are both covered in this study. The impact of mass and heat transmission along the boundary layer is investigated in an equilibrium process. Using the method of similarity transformation, the controlling partial differential equations are changed into ordinary differential equations. The results are confirmed using the bvp4c Matlab built-in programme, and the altered equations are resolved utilizing a 4th order Runge Kutta based shooting method. Reversible and irreversible processes, activation energy, chemical reactions, Deborah numbers, and rotation parameters are some of the parameters for which the results are offered in tables and graphs. The prior objective of this study is to examine the impact of activation energy and chemical reactions on Maxwell fluid flow in an equilibrium setting. The concentration boundary layer for reversible flows is significantly finer than that of irreversible flows with the influence of activation energy, chemical reaction, and rotation factors. A reduced boundary layer thickness can improve the rates of heat and mass transmission in tremendous applications, such as exchangers of heat and chemical reactors. In this chemical process, sulphuric acid is utilized as a catalyst along with Maxwell fluid which affects the boundary layer reaction rate and selectivity. This is crucial for efficient catalytic process design. Controlling reaction rates using fluid elasticity and reaction kinetics is useful in operations that need accurate product production.

Influence of activation energy and multidiffusive quadratic convective nanoliquid flow past a cone and wedge

The present problem aims to examine the impact of quadratic buoyancy-driven flow nanofluid flow on two specific geometries such as cone and wedge in the presence of binary chemical reactions with activation energy, using liquid hydrogen species. This analysis is relevant for various industrial applications and are widely used in thermal energy storage devices for cooling or heating processes. The fluid flow model's governing equations are numerically solved using a fifth-order boundary value approach in matrix laboratory (MATLAB). In order to obtain the numerical solution, we initially transformed the coupled equations of the flow model and the partial differential equations into ordinary differential equations using similarity variables. The graphs and tables illustrate the importance of different physical factors that impact fluid flow and heat transfer. The quadratic combined convection parameter leads to an augmentation in fluid velocity while also inducing an elevation in frictional forces between the object's surface and the fluid. The increased in values of Schmidt number cause a decrease in mass diffusivity, which in turn leads to lower concentration profiles and improved mass transport efficiency. The activation energy is directly proportional to the decreased amplitude of the concentration profiles of liquid hydrogen species.

Influence of activation energy in steady state hydro dynamic non-Newtonian nano fluid with mobile microorganisms

The purpose of this article is to investigate the activation energy associated with bioconvection nano flow propagation via Riga plate with Arrhenius impact. Electricity flows through the fluid with a Lorentz force that alters in vertical direction. A Riga plate is considered when a magnetic electro force is applied. Casson and activation energy are included in the governing equations. The model is based on a Riga plate with a stretchy sheet that can represent bioconvection, the movement of microorganisms in two-phase nano-liquid flows. Novelty of this research is to explore the thermal and mass transport across a Riga plate of a Casson flow in steady, laminar, and MHD incompressible flow with bioconvection, and activation energy impacts. The governing PDEs are organized by the application of basic conservation laws, and they are subsequently transformed into equivalent ordinary differential equations. An evaluation of the present analysis is conducted using bvp4c, are displayed graphically. Results indicates magnetic field and Rayleigh bioconvection wither the velocity. Temperature profiles tend to be increased by Brownian motion.

Thermoacoustic parametric instability of premixed ammonia flames propagating downwards in an open-closed tube

This work investigates the self-excited thermoacoustic parametric instability of downward propagating laminar premixed ammonia flames in an open-closed combustion tube. NH3/O2/N2 flames were propagated at different laminar burning velocities at equivalence ratios of ɸ = 0.8 and ɸ = 1.2. Different unstable flame regimes were observed through pressure fluctuation measurements and synchronized high-speed imaging capturing the lateral and longitudinal perspectives of flame propagation. The observed propagation speed of quasi-planar flames showed a strong correlation with the calculated laminar burning velocities of NH3/O2/N2 mixtures. For the first time, the cellular structures of laminar premixed ammonia flames at the onset of parametric instability were clearly observed from the present experimental approach. The experimental cellular flame wavenumbers and acoustic velocity fluctuation amplitudes at the onset of parametric instability are in qualitative agreement with the theory of stability of laminar flames under acoustic excitation. Experiments have shown that NH3/O2/N2 flames are more unstable than CH4/O2/N2 flames at the same laminar burning velocity independent of Lewis number within the range of tested conditions. The influence of activation energy on parametric instability is investigated through a comparative thermoacoustic analysis between two different fuels at varied equivalence ratios. Ammonia flames are characterized by large overall activation energy and Zeldovich numbers compared to hydrocarbon flames. This work elucidates how this unique property characterizes the acoustic instability of downward propagating premixed ammonia flames in a tube based on classical theories on acoustic instability of laminar premixed flames.

Impact of chemical reactions that generate and absorb heat in the flow induced by a squeezing porous slider

The three-dimensional flow of a viscous fluid induced by an expanding or contracting porous slider under the influence of activation energy with exothermic and endothermic chemical reactions is explored in this study. Moreover, the amount of fluid injected to levitate the slider changes over time according to where it is at any instant. With the aid of similarity variables, the modelling equations relating to the fluid flow are converted into a system of ordinary differential equations. Then, this system of equations is solved numerically with the help of the Runge–Kutta Fehlberg’s fourth fifth-order method (RKF-45). Graphs are used to analyze the impact of the various parameters on the flow, thermal and concentration fields. Results reveal that the velocity profiles get smaller as the wall dilation parameter rises. An anticipated boundary layer development next to the wall results from increased Reynolds number. The temperature profile for an exothermic process has a diminishing influence as the activation energy parameter increases, whereas the opposite consequences are obtained for an endothermic reaction. For an exothermic reaction, the temperature profile rises as the chemical reaction parameter values increase. However, the opposite consequences can be seen for an endothermic reaction.

Effect of heat generation and activation energy on MHD maxwell fluid with multiple slips

This research delves into Maxwell fluid flow's intricate fluid dynamics, as well as heat-mass transfer features over a porous horizontal plate. The investigation encompasses magnetohydrodynamics, heat generation, radiation, chemical reactions, and the influence of activation energy. Furthermore, the study integrates slip conditions for temperature, velocity, and concentration gradients at the interface between the fluid and solid surfaces. After formulating the governing equation with the abovementioned parameters, the partial differential equations are changed into ordinary ones through a similarity revolution. The results of the bvp4c solver in MATLAB provide significant insights into how various physical parameters interact and influence the flow dynamics and heat-mass transfer characteristics. This research's primary aim and objective is to comprehensively compare plots generated for different parameters under both no-slip and slip conditions by considering fixed values as Q = 0-0.3, Sc = 1–4, Ec = 0–1, Pr = 1–4, σ = 0–2, E = 0.1-0.7, λ = 0–2. The primary discoveries of this study indicate that with an increase in the power index, there is a decline in the concentration profile. In contrast, an increase in the activation energy leads to an elevation in this profile. An important revelation from this research is the significant decrease observed in the concentration profile as the activation energy parameter is raised.

Stagnation-point flow of Williamson fluid along a stretched plate with convective thermal condition and activation energy

The implication of a stagnation-point flow together with the influence of activation energy in a Williamson fluid, which consists of tiny particles, over an expansive plate is analyzed numerically. Conditions of convective heat and mass motion with features of irregular movement and thermal-migration of particles influenced by viscous dissipation and convective heat surface condition are checked in the study. The conversion of the model equations from the initially formulated partial derivatives to ordinary ones is implemented by similarity transformations while an unconditionally stable Runge-Kutta-Fehlberg integration plus shooting technique are then used to complete the integration. Various interesting effects of the physical parameters are demonstrated graphically and explained appropriately in order to make accurate predictions. Moreover, the accuracy of the solution is verified by comparing the values of the skin friction factor with earlier reported ones in literature under limiting constraints. It is worth mentioning that the velocity profiles flatten down as the magnitude of the magnetic field factors expands but this causes a boost in the fluid’s temperature. The concentration field also appreciates with activation energy but depreciates with chemical reaction and Schmidt number.

Influence of Activation Energy, Variable Viscosity, Partial Slip on MHD Mixed Convective Heat Transfer Flow of Nanofluid Past Stretching Surface with Newtonian Cooling

Influence of Activation Energy, Variable Viscosity, Partial Slip on MHD Mixed Convective Heat Transfer Flow of Nanofluid Past Stretching Surface with Newtonian Cooling

Motile microorganisms hybrid nanoliquid flow with the influence of activation energy and heat source over a rotating disc

The present article examines the consequences of a magnetic field, Hall current, and thermal radiation on the spinning flow of hybrid nanofluid (HNF) across a revolving disc. The core objective of the study is to improve the energy transference rate through hybrid nano liquid for industrial and engineering operations. The HNFs have advanced thermophysical characteristics. Therefore, in the current study, a superior class of nanomaterials (carbon nanotubes (CNTs) and Al2O3) are added to the base fluid. The modeled equations are demoted to a dimensionless set of Ordinary differential equations (ODEs) through similarity conversion and are analytically solved by engaging the homotopy analysis method. The physical constraints’ effect on energy, velocity, motile microorganism, and mass profiles have been drawn and discussed. For accuracy, the results are compared to the published studies, which ensures the accuracy and reliability of the technique and results. It is observed that the energy communication rate lessens with the flourishing values of thermal radiation and for Hall current. Furthermore, it is noted that due to its carbon–carbon bonding in CNTs, it has a greater tendency for energy propagation than Al2O3 nanoparticles.

Numerical computation of Brownian motion and thermophoresis effects on rotational micropolar nanomaterials with activation energy

The current article investigates the numerical study of the micropolar nanofluid flow through a 3D rotating surface. This communication may manipulate for the aim such as the delivery of the drug, cooling of electronic chips, nanoscience and the fields of nanotechnology. The impact of heat source/sink is employed. Brownian motion and thermophoresis aspects are discussed. The rotating sheet with the impacts of Darcy-Forchheimer law is also scrutinized. Furthermore, the influence of activation energy is analyzed in the current article. The numerical analysis is simplified with the help of befitted resemblance transformations. The succor of the shooting algorithm with built-in solver bvp4c MATLAB software is used for the numerical solution of nonlinear transformed equations. The consequences of different physical factors on the physical engineering quantities and the subjective fields were examined and presented. According to outcomes, it can be analyzed that the flow profile declined with the rotational parameter. It is observed that angular velocity diminishes via a larger porosity parameter. Furthermore, the temperature gradient is declined via a larger magnitude of the Prandtl number. The heat transfer is enhanced in the occurrence of Brownian motion. The activations energy parameter causes an increment in the volumetric concentration field. Moreover, the local Nusselt number is reduced via a greater estimation of the porosity parameter.

Darcy flow of convective and radiative Maxwell nanofluid over a porous disk with the influence of activation energy

This study reveals an incompressible steady Darcy flow of Maxwell nanofluid by a porous disk with the impact of activation energy. The liquid flow is due to a stretchable rotating disk. The heat equation also includes the impact of heat source/sink and radiation for the purpose of heat transportation. The von Karman transformations are utilized to gain the dimensionless form of ordinary differential equations (ODEs). The solutions are visualised in the form of graphical results using bvp 4c method in Matlab software. The ranges of the associated physical parameters as, 0.0≤β≤0.9, 0.0≤M≤0.9, 0.0≤λ≤1.5, 0.1≤R≤0.9, −0.2≤s≤1.3, 0.3≤Bi≤0.6, 0.0≤γ≤0.15, 0.1≤Nt≤2.0, 0.2≤Nb≤0.8, 0.0≤Rd≤0.3, 0.0≤σ≤1.5, and 0.0≤E≤0.9 are provided for the graphical solutions developed for the problem. The data of Nussetl and Sherwood numbers are presented here with regard to various physical parameters. According to the numerical results, increasing the Deborah number has a trend to decrease the radial curves. Moreover, the temperature distribution is increased considerably for rising the radiation parameter and the higher rate of the rotation parameter shows a weaker concentration trend. To validate the numerical approach, an excellent comparison is established using a tabular description. To sum up, the current study effectively fills a gap in the antecedent literature.

Peristaltic transport of MHD Ree–Eyring fluid through a flexible channel under the influence of activation energy

Peristalsis of Ree–Eyring non-Newtonian fluid is significant to investigate the rheological features of biological fluids such as blood, saliva, intravascular fluids, intracellular fluids, and interstitial fluids. As a consequence of this development, the present article explores the cross-diffusive magnetohydrodynamic peristaltic transport of a Ree–Eyring fluid conveying tiny particles through a flexible porous channel under the influence of activation energy. A lubrication approach is adopted to reduce the complexity of the system. The analytical solution is achieved for the velocity field. In addition, the Runge–Kutta-based shooting technique is employed to solve the temperature and fluid concentration equations. Dual solutions are executed for the Newtonian and Ree–Eyring fluid cases and discussed through tabular and graphical findings for several sets of pertinent parameters. In this investigation, it is perceived that an enhancement in the Darcy number optimizes the velocity field. The fluid temperature rises with elevated values of the Brinkman and Dufour numbers whereas the reverse trend is noticed in the fluid concentration field for Soret and activation energy parameters. Moreover, the obtained outcomes are applicable to a variety of fields in the medical sciences and engineering, such as the radiosurgery, the spectroscopy, the optoelectronics, the power conversion devices, and the nuclear reactor cooling.

Double-diffusive nonlinear convection dusty fluid flow over a cone under the influence of activation energy

Double-diffusive nonlinear convection dusty fluid flow over a cone under the influence of activation energy

Modified Buongiorno's model for the analysis of chemically reacting jet flow of ternary hybrid nanofluid under the influence of activation energy and bio‐active mixers

AbstractIn the modern era, the heat transfer is the basic need in every field of sciences and engineering. To augment the energy transfer, the ternary hybrid nanofluid (Thnf) has been used. After the successful nanofluid working performance, the researchers used this idea in many physical situations. Later on, the researchers tried to further improve the performance of nanofluid with high stability. Motivated from the unique practical applications of hybrid nanofluid, in the present analysis, we have considered ternary nanoliquid, which is obtained by the suspension of three nano particulates in base fluids. The aim of the present research is to highlight the thermal applications of ternary nanofluid in the vertical stretching wall jet flow. The suspension of three different nano solid particles is considered in a base liquid water a jet flow over a vertical extending sheet is addressed. In addition to this, the presence of chemical reaction in the concentration, thermophoresis effect in the energy equation and heat source is also addressed. To model the present phenomena of flow using the modified Buongiorno's model, that highlights the impact of Brownian motion and thermophoresis effect. The present flow problem is modelled in terms of PDE's. To transform the obtained model, we use appropriate similarity variables. The transform model is then solved numerically, using the fast convergence numerical PCM approach (parametric continuation method). The solution obtained is shown through graphical representation by indicating the impact of pertinent flow parameters. Finally, from the present results, we obtained that the performance of Thnf is effective in water as compared to hybrid nanoliquid and mono nanofluid. Furthermore, the motile gyrotactic microbes profile gets lower with the varying values of bioconvection Lewis number and Peclet number.

Mathematical analysis of casson fluid flow with energy and mass transfer under the influence of activation energy from a non-coaxially spinning disc

A Casson fluid is the most suitable rheological model for blood and other non-Newtonian fluids. Casson fluids hold yield-stress and have great significance in biomechanics and polymer industries. In this analysis, a numerical simulation of non-coaxial rotation of a Casson fluid over a circular disc was estimated. The influence of thermal radiation, second-order chemical reactions, buoyancy, and heat source on a Casson fluid above a rotating frame was studied. The time evolution of secondary and primary velocities, solute particles, and energy contours were also examined. A magnetic flux of varying intensity was applied to the fluid flow. A nonlinear sequence of partial differential equations was used to describe the phenomenon. The modeled equations were reduced to a non-dimensional set of ordinary differential equations (ODEs) using similarity replacement. The obtained sets of ODEs were further simulated using the parametric continuation method (PCM). The impact of physical constraints on energy, concentration, and velocity profiles are presented through figures and tables. It should be noted that the effect of the Casson fluid coefficient, the Grashof number, and the magnetic field reduces the fluid’s primary velocity contour. The mass transfer field decreases with the action of constructive chemical reactions, but is augmented by the effects of destructive chemical reactions. The accelerating trend in Schmidt number lowers the mass profile, while it is enhanced by increasing values of activation energy and Soret number.

Influence of Activation Energy on the Hybrid Nanofluid Flow over a Flat Plate with Quadratic Thermal Radiation: An Irreversibility Analysis

Dissipative (Water – Iron (II, III) Oxide – MWCNT) hybrid nanofluid dynamics over a flat plate at varied Lorentz forces, volume fraction, and activation energy are unknown when quadratic thermal radiation is taken into account. Paper's novelty is addressing this gap, which is to examine the impact of activation energy on the hybrid nanofluid flow by a flat plate with viscous dissipation and magnetic field. Nonlinear ordinary differential equations are constructed from flow-driven equations, and the MATLAB bvp4c solver is used to solve them. Entropy generation increases as the volume fraction of nanoparticles increases, and the rate of mass transfer decreases as the activation energy parameter increases are the major findings of this study. As thermal radiation and Eckert number increase, observed an increase in the fluid temperature. Increasing the volume fraction of nanoparticles causes a rise in shear stress, while increasing the magnetic field parameter decreases it. It is noticed that, when magnetic field parameter () takes input in the range , skin friction coefficient decreases at a rate of 1.10078 per unit value of magnetic field parameter. It is detected that, when Eckert number increases, Nusselt number decreases. The decrement rates are observed as 0.02457 when Eckert number takes input in the range . It is discovered that the mass transfer rate decreases at a rate of 0.08123 when activation energy parameter takes input in the range .

Erratum: "Fractional blood flow in rotating nanofluid with different shapes nanoparticles in the influence of activation energy and thermal radiation" [Chaos 31, 093109 (2021)

First Page

Influence of activation energy on triple diffusive entropy optimized time-dependent quadratic mixed convective magnetized flow

The flow over a wedge with activation energy and chemical reaction gains widespread applications in compound creations, food processing, insulation, oil reservoirs, catalysis, etc. The vast applicability of activation energy with a binary chemical reaction comprising multiple diffusions and the time-dependent nature of the entropy-optimized flow has drawn our attention to this work. The consequences of time, activation energy, liquid hydrogen and oxygen diffusions, and magnetic field over a wedge in the quadratic combined convection flow with entropy analysis are explored to achieve more mechanically realistic outcomes. The nonlinear dimensional coupled partial differential equations (PDEs) that govern the modelled phenomenon are tackled with non-similar transformations, the Quasilinearization technique followed by an implicit finite difference scheme and Varga’s matrix inverse procedure. The entropy generation can be minimized by upsurging the magnitude of the temperature difference ratio attribute . The higher wedge angle results in a lower fluid motion.

Influence of activation energy and applied magnetic field on triple-diffusive quadratic mixed convective nanoliquid flow about a slender cylinder

Influence of activation energy and applied magnetic field on triple-diffusive quadratic mixed convective nanoliquid flow about a slender cylinder

On the role of bioconvection and activation energy for time dependent nanofluid slip transpiration due to extending domain in the presence of electric and magnetic fields

A mathematical analysis for slip effects on MHD nanofluid in the presence of electromagnetic field and gyrotactic microorganisms is considered. The influence of activation energy and thermal radiation are also discussed. The transportation of nanofluids provides a feasible option for the enhancement of thermal distribution. A rather new aspect of this work is the diffusion and bioconvection of motile microorganisms. It may avoid possible settling of nano-entities. A system of highly non-linear partial differential equations is transformed into Ordinary differential equations by using suitable similarity transformation. The converted ordinary differential equations are then solved numerically by utilizing the shooting technique is built-in function bvp4c solver on the plate form of commercial software Matlab. The results obtained are verified through acceptable agreement with those of the existing one as a special case. The quantities of interest are observed physically. The characteristics of various emerging parameters on the velocity field, temperature distribution and volumetric concentration of nanoparticles, microorganism concentration as well as skin friction coefficient, the gradient of temperature, local Sherwood number, and density number of motile microorganisms are interpreted and reflected in tabulated and graphical form. It is noticed that velocity decreases with the rising values of M . Also, the temperature rises directly with Nb and Nt . With the growing values of Lb , the microorganism profile does down.