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Nonlinear radiated MHD flow of nanoliquids due to a rotating disk with irregular heat source and heat flux condition
This research is made to visualize the nonlinear radiated flow of hydromagnetic nano-fluid induced due to rotation of the disk. The considered nano-fluid is a mixture of water and Ti6Al4V or AA7072 nano-particles. The various shapes of nanoparticles like lamina, column, sphere, tetrahedron and hexahedron are chosen in the analysis. The irregular heat source and nonlinear radiative terms are accounted in the law of energy. We used the heat flux condition instead of constant surface temperature condition. Heat flux condition is more relativistic and according to physical nature of the problem. The problem is made dimensionless with the help of suitable similarity constraints. The Runge-Kutta-Fehlberg scheme is adopted to find the numerical solutions of governing nonlinear ordinary differential systems. The solutions are plotted by considering the various values of emerging physical constraints. The effects of various shapes of nanoparticles are drawn and discussed. 2018 Elsevier B.V. -
Nonlinear radiative flow of casson nanoliquid past a cone and wedge with magnetic dipole: Mathematical model of renewable energy
Solar energy is an important source of energy for all the living things. Other sources of energy such as electricity and heat can be converted from solar radiation. The recent advanced technologies are utilized to convert solar energy into electricity. In this direction, nanoliquids are quite useful because they directly absorb or scatter solar radiation. Nanofluids are selected to be best aspirant for the development of renewable energy. They are successfully utilized in the processes of renewable energy. Due to such importance of nanofluids, we investigate the effects of nanoparticles on nonlinear convective and radiative flow of Casson liquid. Two cases are considered namely flow due to a cone and flow due to a wedge. In addition to traditional temperature dependent heat source aspect an exponential space dependent heat source effect is examined. Explicitly heat/mass transfer mechanism is analysed due to prescribed linear surface temperature/particles volume fraction. Problem formulation is presented using conservation laws of mass, momentum, energy and nanoparticles volume fraction under boundary layer approximations. The solutions to the dimensionless problem are computed via Runge-Kutta-Fehlberg based shooting method. Results are plotted and examined. The exponential space dependent and thermal dependent heat source aspects are dominates on thermal field. Further, heat and mass transfer rates are higher in case of flow created by cone than flow created by wedge. The liquid velocity is higher in the case of flow due to wedge than flow due to cone case. 2018 by American Scientific Publishers All rights reserved. -
Magnetohydrodynamic squeezing two-phase flow of particulate suspension in a rotating channel with transpiration cooling
This article addresses the time-dependent two-phase magnetohydrodynamic squeezing flow of dusty liquid. The fluid flow is considered in a rotating channel. The flow is constructed by squeezing of an upper plate and stretching of the lower plate and relevant equations are obtained. Numerical results are computed by utilizing shooting method along with the RKFehlberg scheme. The obtained solutions are validated by comparison with the existing analytical solutions. The effects of pertinent parameters on velocities of both phases are comprehensively discussed through graphical results. The numerical values of shear stress of both phases at lower and upper walls are also tabulated. Furthermore, the slope of the linear regression line through data points is determined in order to quantify the increase/decrease. Numerical simulations disclosed that the normal and transverse velocities are decreased due to stronger Coriolis force. It is also established that the velocities of the fluid phase are higher than that of the dust phase IMechE 2018. -
Nonlinear convection in nano Maxwell fluid with nonlinear thermal radiation: A three-dimensional study
The combined effects of nonlinear thermal convection and radiation in 3D boundary layer flow of non-Newtonian nanofluid are scrutinized numerically. The flow is induced by the stretching of a flat plate in two lateral directions. The mechanism of heat and mass transport under thermophoretic and Brownian motion is elaborated via implementation of the thermal convective condition. The prevailing two-point nonlinear boundary value problem is reduced to a two-point ordinary differential problem by employing suitable similarity transformations. The solutions are computed by the implementation of homotopic scheme. At the end, a comprehensive parametric study has been conducted to analyze the typical trend of the solutions. It is found that the nanoparticle volume fraction and temperature profiles are stronger for the case of solar radiation in comparison with problem without radiation. 2017 Faculty of Engineering, Alexandria University -
Dynamics of magneto-nano third-grade fluid with brownian motion and thermophoresis effects in the pressure type die
The non-transient dynamics of the non-Newtonian third-grade liquid driven by pressure type die in the presence of nanoparticles is studied. The fluid is dissipating and its properties are taken as unvarying. The governing partial differential equations system is developed and they are numerically solved after non-dimensionalization. The significance of pertinent parameters on flow fields is analyzed and discussed. The thermal field shows dual behaviour in the flow domain due to the impact of magnetism, Brownian motion and thermophoresis. 2019 by American Scientific Publishers All rights reserved. -
Nonlinear convective and radiated flow of tangent hyperbolic liquid due to stretched surface with convective condition
The current study compacts with effect of nonlinear convection and radiation on tangent hyperbolic fluid flow of through a convectively heated vertical surface. The converted set of boundary layer equations are solved numerically by Runge-Kutta-Fehlberg method. The effect of various pertinent parameters on flow and heat transfer characteristics are discussed with tabulated numerical values and deliberate figures. Additionally, the skin friction coefficient and Nusselt number are also presented. We noticed that, the skin friction factor and heat transfer rates are higher in presence of nonlinear convection than its absence. Further, velocity profile decreases by increasing power law index but establishes opposite results for skin friction. 2017 -
Significance of exponential space- and thermal-dependent heat source effects on nanofluid flow due to radially elongated disk with Coriolis and Lorentz forces
In this paper, the nanofluid flow near an infinite disk which stretches in the radial direction in the presence of exponential space-based heat source (ESHS) and thermal-based heat source (THS) is investigated. The Brownian motion and thermophoresis effects are accounted to study the nanofluids. Effects of radial magnetism and the Coriolis force are also deployed. The pertinent nonlinear equations are approximated under boundary layer notion and modified von Km transformations. The subsequent nonlinear differential system is treated via shooting method. The impacts of controlling parameters on flow profiles are discussed and depicted with the aid of graphs. Results show that as the ESHS and THS parameters increase, the thermal field increases. However, ESHS phenomenon is highly influential than THS phenomenon on energy transport and its gradient. Further, it is found that thermophoresis slip mechanism has more effect on heat transport rate than the Brownian motion. 2019, Akadiai Kiad Budapest, Hungary. -
Effects of chemical reaction and partial slip on the three-dimensional flow of a nanofluid impinging on an exponentially stretching surface
The three-dimensional mixed convection boundary layer flow of a nanofluid induced by an exponentially stretching sheet is numerically investigated in the presence of thermal radiation, heat source/sink and first-order chemical reaction effects. The adopted nanofluid model incorporates the effects of Brownian motion and thermophoresis into the mathematical model. The first-order velocity slip boundary conditions are also taken into account. The governing boundary layer equations are transformed into a set of nonlinear ordinary differential equations by employing suitable similarity variables. The resultant equations are solved numerically using the Runge-Kutta-Fehlberg method. Obtained solutions are compared with previous results in a limiting sense from the literature, demonstrating an excellent agreement. To show the typical trend of the solutions, a parametric study is conducted. The axial velocity, transverse velocity, temperature and nanoparticle volume fraction profiles as well as the skin-friction coefficient, Nusselt and Sherwood numbers are demonstrated graphically as a representative set of numerical results and discussed comprehensively. 2017, SocietItaliana di Fisica and Springer-Verlag Berlin Heidelberg. -
Flow of nanoliquid past a vertical plate with novel quadratic thermal radiation and quadratic Boussinesq approximation: Sensitivity analysis
The effects of quadratic thermal radiation and quadratic Boussinesq approximation are investigated on the heat transport of a 36 nm Al2O3 ? H2O nanofluid over a vertical plate. The modified Buongiorno model is used in the analysis that includes the effectual thermophysical properties of the nanofluid and the key slip mechanisms. Experimentally verified correlations are used for the thermophysical properties. The reduced nonlinear differential problem is solved numerically by the Finite Difference Method (FDM). Flow profiles are displayed and analyzed for changes in dimensionless parameters. Further, the heat transfer flux at the wall is analyzed for interactive impacts of the buoyancy ratio, Brownian random motion, and thermophoresis parameters using the face-centered Central Composite Design (CCD) of the Response Surface Methodology (RSM). A sensitivity analysis is carried out for the heat transfer flux of the nanoliquid. Quadratic thermal radiation was found to improve the temperature profile. Furthermore, the mechanisms of Brownian random motion and thermophoresis have a negative sensitivity towards the rate of heat transfer. In various thermal applications like solar collectors, the density variation in terms of temperature differences is significantly high. Such phenomena can be accurately modeled by utilizing the quadratic Boussinesq approximation and the novel quadratic thermal radiation aspect. 2020 Elsevier Ltd -
Response surface optimization of heat transfer rate in Falkner-Skan flow of ZnO ? EG nanoliquid over a moving wedge: Sensitivity analysis
In this work, the optimization of the heat transfer rate in the Falkner-Skan flow of ethylene glycol-based ZnO nanoliquid passing through a moving wedge is performed using the Response Surface Methodology (RSM). The experimentally estimated nanoliquid properties are included in the calculations for realistic modeling. The heat transfer rate is optimized through the use of the numerical experiment based on the face-centered central composite design (CCF). The sensitivity of the heat transfer rate is evaluated using the obtained quadratic model. The impact of the relevant parameters is displayed graphically using the finite difference method-based solution procedure and analyzed in detail. The interactive impacts of the key parameters are also evaluated using three-dimensional surface plots. The maximum sensitivity of the heat transfer rate is towards the moving wedge parameter. The optimized rate of heat transfer occurs at the high levels of the radiation aspect, moving wedge parameter, and nanoparticle volume fraction. The interactive impacts of the nanoparticles volume fraction and the Falkner-Skan index were found to be non-linear. The movement of the wedge was found to have a significant impact on both the flow field and the rate of heat transfer. 2021 Elsevier Ltd -
Significance of quadratic thermal radiation and quadratic convection on boundary layer two-phase flow of a dusty nanoliquid past a vertical plate
Boundary layer two-phase flow of particulate Al2O3-H2O nanoliquid over a vertical flat plate is studied numerically subjected to the aspects of quadratic thermal convection and quadratic thermal radiation. The Khanafer-Vafai-Lightstone monophasic nanofluid model (KVL model) and Saffman's dusty fluid model are used for the equations governing the flow of dusty nanoliquids. The quadratic Boussinesq approximation is used together with the Prandtl's boundary layer approximation. The non-linear problem is treated with the finite difference method. Surface plots and streamlines are presented to visualize the results. A comparison of linear thermal radiation, quadratic thermal radiation, and nonlinear thermal radiation is performed. Among the three types of radiation, the greatest heat transfer is observed in nonlinear thermal radiation followed by quadratic thermal radiation and linear thermal radiation. Also, in the presence of quadratic convection, the heat transport, and velocity field get enhanced. It is found that the presence of Al2O3 nanoparticles of 3% volume concentration in particulate water effectively advances the heat transport of the system. However, heat transport gets reduced by increasing the mass fraction of dust particles. Furthermore, in the presence of a transverse magnetic field, the velocity of the dusty nanoliquid gets reduced. 2020 -
Statistical analysis of stagnation-point heat flow in Williamson fluid with viscous dissipation and exponential heat source effects
This analysis explores the effect of the novel exponential space-dependent heat generation factor on the stagnation-point Williamson fluid flow over a stretchable surface. The heat transport phenomenon is carried out by the addition of viscous and Ohmic dissipations. Similarity transformations are applied to the nonlinear system of partial differential expressions that arise by the flow. The nonlinear ordinary differential system hence obtained is solved to visualize the role of different constraints graphically. Statistical methods such as correlation, probable error, and regression are utilized. The probable error is evaluated to calculate the reliability of the computed correlation factors. The study reveals that the velocity phenomenon is reduced by incrementing the Weissenberg parameter. The velocity of the hydromagnetic liquid is lesser than the velocity of magnetohydrodynamic fluid flow. Also, the higher heat generation factor gives a boost to the temperature of the flowing material. 2020 Wiley Periodicals LLC -
Exponential heat source effects on the stagnation-point heat transport of Williamson nanoliquid with nonlinear Boussinesq approximation
The nonlinear two-point partial differential boundary value problem associated with the nano-pseudoplastic material flow and heat transport subject to nonlinear Boussinesq approximation is computed and explored statistically. Heat transportation features are analyzed by the consideration of an exponential space-related heat source and the Buongiorno model of nanofluids. The boundary-driven expressions of the physical phenomenon are coupled and highly complicated due to the consideration of nonlinear convection terms. Reasonable variables are employed to reform the partial differential equations into a system of ordinary differential expressions and are solved numerically. Furthermore, correlation and regression techniques are employed for the statistical evaluation of the phenomenon. The probable error is implemented to calculate the reliability of the computed correlation factors. The exponential index and Schmidt number are positively correlated with the reduced skin friction coefficient whereas the other parameters are negatively correlated with it. The heat transfer rate is improved predominantly by the nonlinear thermal convection parameter. The temperature is enhanced by the intensification of the exponential-based heat source factor. The temperature and concentration profiles are boosted by incrementing the Biot number values. 2021 Wiley Periodicals LLC -
Two-phase flow of dusty Casson fluid with Cattaneo-Christov heat flux and heat source past a cone, wedge and plate
This article addresses the boundary layer flow and heat transfer in Casson fluid submerged with dust particles over three different geometries (vertical cone, wedge and plate). The aspects of Cattaneo-Christov heat flux and exponential space-based heat source (ESHS) are also accounted. At first, the partial differential equations are transformed into a set of ordinary differential equations via appropriate similarity transformations. Resulting equations are solved via shooting method coupled with the Runge-Kutta-Fehlberg-45 integration scheme. The consequences of dimensionless parameters on velocity and temperature fields of both fluid and dust particles phase are analyzed. The rate of increment/decrement in the skin friction as well as the Nusselt number for various values of physical parameters are also estimated via slope of linear regression line using data points. 2018 Trans Tech Publications, Switzerland. -
Heat and mass transfer effects on non-newtonian fluid flow over an unsteady stretching surface with viscous dissipation and thermal radiation
This paper analyzes the flow, heat and mass transfer characteristics of non-Newtonian Casson fluid towards an unsteady permeable stretching surface. An external transverse magnetic field is applied normal to the sheet. The effects of viscous dissipation and thermal radiation are considered in energy equation. Rosseland approximation is used to model the radiative heat transfer. With the aid of similarity transformations, the unsteady boundary layer equations are transformed into a set of non-linear ordinary differential equations. Numerical solutions of resulting non-linear differential equations are solved by using efficient fourth-fifth order Runge-Kutta Feldberg method. The obtained numerical results are compared and found to be in good agreement with previously published results. Behavior of emerging parameters on velocity, temperature and concentration profiles are discussed and presented graphically. Further, variation of the reduced skin friction coefficient, Nusselt and Sherwood number against physical parameters in graphical and tabular form are presented and discussed in detail. It is found that the effects of thermal radiation and viscous dissipation are favorable for thickening the thermal boundary layer. 2018 Pushpa Publishing House, Allahabad, India. -
RayleighBard convection in a non-Newtonian dielectric fluid with MaxwellCattaneo law under the effect of internal heat generation/consumption
Purpose: The study of instability due to the effects of MaxwellCattaneo law and internal heat source/sink on Casson dielectric fluid horizontal layer is an open question. Therefore, in this paper, the impact of internal heat generation/absorption on RayleighBard convection in a non-Newtonian dielectric fluid with MaxwellCattaneo heat flux is investigated. The horizontal layer of the fluid is cooled from the upper boundary, while an isothermal boundary condition is utilized at the lower boundary. Design/methodology/approach: The Casson fluid model is utilized to characterize the non-Newtonian fluid behavior. The horizontal layer of the fluid is cooled from the upper boundary, while an isothermal boundary condition is utilized at the lower boundary. The governing equations are non-dimensionalized using appropriate dimensionless variables and the subsequent equations are solved for the critical Rayleigh number using the normal mode technique (NMT). Findings: Results are presented for two different cases namely dielectric Newtonian fluid (DNF) and dielectric non-Newtonian Casson fluid (DNCF). The effects of Cattaneo number, Casson fluid parameter, heat source/sink parameter on critical Rayleigh number and wavenumber are analyzed in detail. It is found that the value Rayleigh number for non-Newtonian fluid is higher than that of Newtonian fluid; also the heat source aspect decreases the magnitude of the Rayleigh number. Originality/value: The effect of MaxwellCattaneo heat flux and internal heat source/sink on Rayleigh-Bard convection in Casson dielectric fluid is investigated for the first time. 2020, Emerald Publishing Limited. -
Effectiveness of Hall current and exponential heat source on unsteady heat transport of dusty TiO2-EO nanoliquid with nonlinear radiative heat
The problem of exponential heat source across a flowing nanofluid (TiO2-EO; titanium oxide-Engine oil) containing tiny dust particles on a deformable planar plate has been an open question in meteorology. In this paper, the boundary layer transient two-phase flow of dusty nanoliquid on an isothermal plate which is deforming with time-dependent velocity in the presence of exponential heat source is studied. The impacts of Hall current, nonlinear radiative heat and an irregular heat source (temperature based heat source and exponential space-based heat source) are also accounted. Dusty nanofluid is the composition of dust particles and nanoliquid (TiO2-EO). Using relevant transformations, the system of PDEs is rehabilitated to the system of ODEs and then treated numerically. Exploration of the impacts of pertinent parameters on velocity and temperature fields is performed via graphical illustrations. Numeric data for skin friction factor and the Nusselt number is presented and their characteristics are analyzed/quantified through the slope of linear regression via data points. 2019 Society for Computational Design and Engineering -
Heat transfer enhancement due to nanoparticles, magnetic field, thermal and exponential space-dependent heat source aspects in nanoliquid flow past a stretchable spinning disk
This study explores the heat transfer characteristics of nanoliquid flowing over a rotating disk in the presence of the applied magnetic field and convective boundary condition. The nanoliquid is flowing due to the rotation of the disk with uniform stretching of a disk along the radial direction. Effects of ESHS (exponential space-related heat source) and THS (thermal-related heat source) are the focal concern of this article. The effective thermal conductivity of ethylene glycol (EG)-based graphene oxide (GO) nanoliquid is estimated by using Nans model whereas effective dynamic viscosity is calculated through Brinkman model. The partial differential system which governed the problem is transformed by using Von-Karman stretching transformations to the ordinary differential system. The subsequent two-point ODBVP (ordinary differential boundary value problem) is treated numerically. The consequence of effective parameters of the problem on different flow fields is illustrated graphically. The numerical values of shear stress and heat transfer rate (Nusselt number) are also calculated. Further, the slope of the data points is determined to quantify the outcome. Validation of the present results is made by direct comparison with the available results and an excellent agreement is found. It is found that the rate of heat transfer increased with nanoparticle volume fraction at the rate 0.4153 and the friction factor increased by increasing nanoparticle volume fraction at the rate 3.0681. The fluctuation rate of Nusselt number due to the variation of the ESHS parameter is almost three times more than that of THS parameter. 2020, Akadiai Kiad Budapest, Hungary. -
Significance of Joule heating and viscous heating on heat transport of MoS2Ag hybrid nanofluid past an isothermal wedge
The problem of flow and heat transport of magneto-composite nanofluid over an isothermal wedge has not been addressed in the literature up to yet. Thus, this article features the laminar transport of Newtonian composite nanomaterial (C2H6O2H2O hybrid base liquid + MoS2Ag hybrid nanoparticles) in the presence of exponential space- and temperature-dependent heat source past an isothermal wedge. An incompressible and electrically conducting fluid is assumed. The effects of Joule heating and viscous heating are also accounted. Single-phase nanofluid model and boundary layer approximation are utilized to govern the equations of flow and heat transport phenomena. The solution of the simplified coupled system of dimensionless constraints is obtained by using the RungeKuttaFehlberg method based on the shooting technique. Detailed analysis of active quantities of interest has been presented and discussed. The interesting physical quantities (friction factors and Nusselt number) are estimated. Also, the slope of the data point is calculated in order to estimate the amount of decrease/increase in physical quantities. 2020, Akadiai Kiad Budapest, Hungary. -
Heat transfer optimization of hybrid nanomaterial using modified Buongiorno model: A sensitivity analysis
Sensitivity analysis of the heat transfer rate in the flow of the hybrid nanoliquid C2H6O2?H2O (base liquid) +MoS2?Ag (nanoparticles) over a wedge using the Response Surface Methodology (RSM) is carried out. The nanomaterial is modeled using the modified Buongiorno nanofluid model (MBNM) that considers the major slip mechanisms and the effective properties of the hybrid nanoliquid. Two distinct heat sources- linear thermal heat source and an exponential space-dependent heat source are taken into account. The governing nonlinear two-point boundary-layer flow problem is treated numerically. The effects of pertinent parameters on the flow fields in the boundary layer region are represented graphically with suitable physical interpretations. The exponential heat source and slip mechanisms are used to study the sensitivities of the heat transfer rate. Both heat source mechanisms lead to an improvement in the temperature profile, in which the effect of the exponential space-related heat source is predominant. The Brownian motion parameter was found to be the most sensitive to the heat transfer rate. 2021