Darcy-Forchheimer flow of MHD Powell-Eyring nanoliquid over a nonlinear radially stretching disk with the impact of activation energy

2021 ◽  
Vol 10 (4) ◽  
pp. 743-753
Author(s):  
Madhu Macha ◽  
Besthapu Prabhakar
Keyword(s):  
Activation Energy ◽  
The Impact ◽  
Forchheimer Flow

scholarly journals Impact of Activation Energy in Darcy-Forchheimer Flow of Cross Nanofluid over a Radial Stretching Surface with Viscous Dissipation and Joule Heating

2021 ◽  
Vol 39 (5) ◽  
pp. 1557-1566
Author(s):  
Cherlacola Srinivas Reddy ◽  
Besthapu Prabhakar
Keyword(s):  
Activation Energy ◽  
Temperature Field ◽  
Differential Equations ◽  
Viscous Dissipation ◽  
Joule Heating ◽  
Graphical Representation ◽  
Energy Parameter ◽  
System Of Nonlinear Equations ◽  
The Impact ◽  
Forchheimer Flow

This framework analyzes the impact of activation energy (AE) and binary chemical reaction (BCR) in Darcy-Forchheimer flow of cross fluid with nanoparticles due to radially stretched surface. Moreover slip, joule heating and viscous dissipation aspects have been considered. Ordinary differential equations acquired from the modelled governing partial differential equations with the assistance of suitable transformations. Further the system of nonlinear equations is computed numerically by Runge-Kutta-Fehlberg method cum shooting technique. Graphical representation has been given to analyze the velocity, temperature and concentration fields with the effect of various pertinent parameters. It is evident that inertia coefficient declines the velocity. Velocity decays for larger Weissenberg number while opposite trend observed in temperature field. Temperature field rises for augmented values of Eckert number. Concentration increases with increase of energy parameter.

scholarly journals A Study of the Impact of Graphite on the Kinetics of SPS in Nano- and Submicron WC-10%Co Powder Compositions

Ceramics ◽  
2021 ◽  
Vol 4 (2) ◽  
pp. 331-363
Author(s):  
Eugeniy Lantcev ◽  
Aleksey Nokhrin ◽  
Nataliya Malekhonova ◽  
Maksim Boldin ◽  
Vladimir Chuvil'deev ◽  
...  
Keyword(s):  
Activation Energy ◽  
Solid Phase ◽  
Continuous Heating ◽  
Diffusion Creep ◽  
Hard Alloys ◽  
Fine Grained ◽  
Plasma Sintering ◽  
Spark Plasma ◽  
The Impact ◽  
Kinetics Of

This study investigates the impact of carbon on the kinetics of the spark plasma sintering (SPS) of nano- and submicron powders WC-10wt.%Co. Carbon, in the form of graphite, was introduced into powders by mixing. The activation energy of solid-phase sintering was determined for the conditions of isothermal and continuous heating. It has been demonstrated that increasing the carbon content leads to a decrease in the fraction of η-phase particles and a shift of the shrinkage curve towards lower heating temperatures. It has been established that increasing the graphite content in nano- and submicron powders has no significant effect on the SPS activation energy for “mid-range” heating temperatures, QS(I). The value of QS(I) is close to the activation energy of grain-boundary diffusion in cobalt. It has been demonstrated that increasing the content of graphite leads to a significant decrease in the SPS activation energy, QS(II), for “higher-range” heating temperatures due to lower concentration of tungsten atoms in cobalt-based γ-phase. It has been established that the sintering kinetics of fine-grained WC-Co hard alloys is limited by the intensity of diffusion creep of cobalt (Coble creep).

scholarly journals Green Preparation, Spheroidal, and Superior Property of Nano-1,3,5,7-Tetranittro-1,3,5,7-Tetrazocane

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Xinlei Jia ◽  
Jingyu Wang ◽  
Conghua Hou ◽  
Yingxin Tan
Keyword(s):  
Activation Energy ◽  
Particle Size ◽  
Fractal Dimension ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Fractal Theory ◽  
Crystal Form ◽  
Decomposition Temperature ◽  
Scanning Calorimetry ◽  
The Impact

Herein, a green process for preparing nano-HMX, mechanical demulsification shearing (MDS) technology, was developed. Nano-HMX was successfully fabricated via MDS technology without using any chemical reagents, and the fabrication mechanism was proposed. Based on the “fractal theory,” the optimal shearing time for mechanical emulsification was deduced by calculating the fractal dimension of the particle size distribution. The as-prepared nano-HMX was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and differential scanning calorimetry (DSC). And the impact sensitivities of HMX particles were contrastively investigated. The raw HMX had a lower fractal dimension of 1.9273. The ideal shearing time was 7 h. The resultant nano-HMX possessed a particle size distribution ranging from 203.3 nm to 509.1 nm as compared to raw HMX. Nano-HMX particles were dense spherical, maintaining β-HMX crystal form. In addition, they had much lower impact sensitivity. However, the apparent activation energy as well as thermal decomposition temperature of nano-HMX particles was decreased, attributing to the reduced probability for hotspot generation. Especially when the shearing time was 7 h, the activation energy was markedly decreased.

Zero Mass Flux Effects on Time Dependent Flow of an Eyring Powell with Activation Energy

2020 ◽  
Vol 9 (3) ◽  
pp. 216-229
Author(s):  
Hussan Zeb ◽  
Hafiz Abdul Wahab ◽  
Umar Khan
Keyword(s):  
Activation Energy ◽  
Mass Flux ◽  
Slip Boundary Condition ◽  
Time Dependent ◽  
Physical Parameters ◽  
Detailed Result ◽  
Discussion Section ◽  
Nonlinear Odes ◽  
Zero Mass ◽  
The Impact

In this work we demonstrated the impacts of zero mass flux in Powell-Eyring fluid over time dependent stretching sheet. We analyzed the Arrhenius activation energy in heat transfer with momentum and thermal slip boundary condition. The governing model is very complex to solve it directly therefore we transform these governed model into a coupled nonlinear ODEs via similarity transformation. After that, we solve these ODEs by using numerica method so calledshooting technique with RK-technique. The characteristics of different beneficial physical parameters on momentum, energy and concentration fields are represented through graphs. We concluded in this work the arising or reducing in the velocity, temperature and concentration fields for the existence of physical parameters. The impact of physical quantities namely skin fraction (Cf), Nusselt (Nux) and Sherwood (Shx) numbers are calculated numerically via tables. In this paper we concluded that the decreases occurring in velocity field for higher values of (M) (H) and (β). Moreover the characteristics of concentration Φ(ζ), temperature θ(ζ) and velocity f′(ζ) gradients are presented for important physical parameters see in detailed Result and discussion section.

Dufour and Soret effects on Darcy-Forchheimer flow of second-grade fluid with the variable magnetic field and thermal conductivity

2020 ◽  
Vol 30 (9) ◽  
pp. 4331-4347 ◽  
Author(s):  
Ambreen A. Khan ◽  
S. Naeem ◽  
R. Ellahi ◽  
Sadiq M. Sait ◽  
K. Vafai
Keyword(s):  
Magnetic Field ◽  
Heat Transfer ◽  
Thermal Conductivity ◽  
Variable Magnetic Field ◽  
Second Grade ◽  
Second Grade Fluid ◽  
Content Type ◽  
Grade Fluid ◽  
The Impact ◽  
Forchheimer Flow

Purpose This study aims to investigate the effect of two-dimensional Darcy-Forchheimer flow over second-grade fluid with linear stretching. Heat transfer through convective boundary conditions is taken into account. Design/methodology/approach Nonlinear coupled governing equations are tackled with a homotopy algorithm, while for numerical computation the computer software package BVPh 2.0 is used. The convergence analysis is also presented for the validation of analytical and numerical results. Findings Valuation for the impact of key parameters such as variable thermal conductivity, Dufour and Soret effects and variable magnetic field in an electrically conducted fluid on the velocity, concentration and temperature profiles are graphically illustrated. It is observed from the results that temperature distribution rises by Dufour number whereas concentration distribution rises by Soret number. The Forchheimer number and porosity parameter raise the skin friction coefficient. The permeable medium has a vital impact and can help in reining the rate of heat transfer. Practical implications The permeable medium has a vital impact and can help in reining the rate of heat transfer. Originality/value To the best of the authors’ knowledge, this study is reported for the first time.

Analysis of the impact of TG data sets on activation energy (E a)

2017 ◽  
Vol 129 (1) ◽  
pp. 553-565 ◽  
Author(s):  
M. Grigiante ◽  
M. Brighenti ◽  
D. Antolini
Keyword(s):  
Activation Energy ◽  
Data Sets ◽  
The Impact

The Combined Effects of Heat Loss and Reversibility on the Propagation of Planar Premixed Counterflow Flames

2018 ◽  
Vol 10 (6) ◽  
Author(s):  
Faisal Al-Malki
Keyword(s):  
Activation Energy ◽  
Finite Elements ◽  
Strain Rate ◽  
Heat Loss ◽  
Constant Density ◽  
Combined Effects ◽  
Stability Of Solutions ◽  
Counterflow Flames ◽  
The Stability ◽  
The Impact

Abstract We study in this paper the combined effect of heat loss and reversibility on the propagation of planar flames formed within the counterflow configuration. The problem has been formulated first using the thermodiffusive model with constant density and then solved numerically using finite elements. The impact of four main parameters, namely the reversibility r, the heat loss κ, the strain rate ε, and the activation energy β, on the propagation of planar flames has been discussed in details. The study has shown that planar flames under reversible conditions behave qualitatively similar to those observed for irreversible reactions, which agree with the asymptotic findings. In the presence of heat loss, the problem exhibits multiplicity of solutions whose number and stability were found to vary according to the strain rate ε. In addition, the study has predicted the existence of a certain value of the reversibility parameter r beyond which the impact of reversibility becomes negligible. Finally, we have examined the stability of the solutions and determined the domain of stability of solutions and their multiplicity for this problem.

scholarly journals Thermal Analysis of 3D Electromagnetic Radiative Nanofluid Flow with Suction/Blowing: Darcy–Forchheimer Scheme

Micromachines ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1395
Author(s):  
Hammad Alotaibi ◽  
Mohamed R. Eid
Keyword(s):  
Activation Energy ◽  
Differential Equations ◽  
Melt Spinning ◽  
Volume Fraction ◽  
Three Dimensional ◽  
Brownian Diffusion ◽  
Force Coefficient ◽  
Catalytic Reactors ◽  
Nanofluid Flow ◽  
The Impact

This paper discusses the Darcy–Forchheimer three dimensional (3D) flow of a permeable nanofluid through a convectively heated porous extending surface under the influences of the magnetic field and nonlinear radiation. The higher-order chemical reactions with activation energy and heat source (sink) impacts are considered. We integrate the nanofluid model by using Brownian diffusion and thermophoresis. To convert PDEs (partial differential equations) into non-linear ODEs (ordinary differential equations), an effective, self-similar transformation is used. With the fourth–fifth order Runge–Kutta–Fehlberg (RKF45) approach using the shooting technique, the consequent differential system set is numerically solved. The influence of dimensionless parameters on velocity, temperature, and nanoparticle volume fraction profiles is revealed via graphs. Results of nanofluid flow and heat as well as the convective heat transport coefficient, drag force coefficient, and Nusselt and Sherwood numbers under the impact of the studied parameters are discussed and presented through graphs and tables. Numerical simulations show that the increment in activation energy and the order of the chemical reaction boosts the concentration, and the reverse happens with thermal radiation. Applications of such attractive nanofluids include plastic and rubber sheet production, oil production, metalworking processes such as hot rolling, water in reservoirs, melt spinning as a metal forming technique, elastic polymer substances, heat exchangers, emollient production, paints, catalytic reactors, and glass fiber production.

scholarly journals Heat Transport Phenomena for the Darcy–Forchheimer Flow of Casson Fluid over Stretching Sheets with Electro-Osmosis Forces and Newtonian Heating

Mathematics ◽  
2021 ◽  
Vol 9 (19) ◽  
pp. 2525
Author(s):  
Xianqin Zhang ◽  
Dezhi Yang ◽  
Muhammad Israr Ur Rehman ◽  
Aamir Hamid
Keyword(s):  
Differential Equations ◽  
Fluid Velocity ◽  
Casson Fluid ◽  
Similarity Transformations ◽  
Governing System ◽  
Electro Osmosis ◽  
The Impact ◽  
Osmotic Effects ◽  
Forchheimer Flow ◽  
Good Agreement

In this study, an investigation has been carried out to analyze the impact of electro-osmotic effects on the Darcy–Forchheimer flow of Casson nanofluid past a stretching sheet. The energy equation was modelled with the inclusion of electro-osmotic effects with viscous and Joule dissipations. The governing system of partial differential equations were transformed by using the suitable similarity transformations to a system of ordinary differential equations and then numerically solved by using the Runge–Kutta–Fehlberg method with a shooting scheme. The effects of various parameters of interest on dimensionless velocity and temperature distributions, as well as skin friction and heat transfer coefficient, have been adequately delineated via graphs and tables. A comparison with previous published results was performed, and good agreement was found. The results suggested that the electric and Forchheimer parameters have the tendency to enhance the fluid velocity as well as momentum boundary layer thickness. Enhancements in temperature distribution were observed for growing values of Eckert number. It was also observed that higher values of electric field parameter diminished the wall shear stress and local Nusselt number.

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