Mixed Convection Flow Of Nanofluid Research Articles

Electrically conducting mixed convective nanofluid flow past a nonlinearly slender Riga plate subjected to viscous dissipation and activation energy

This paper reports the mass and energy transmission characteristics of an electrically conducting mixed convective nanofluid flow past a stretching Riga plate. An additional effect of viscous dissipation, Arrhenius activation energy and heat source is also studied. The energy and mass transmissions are evaluated by a zero-mass flux of nanoparticle and convective boundary conditions. Buongiorno’s relations are proposed for the Brownian motion and thermophoretic diffusion. The similarity substitutions are employed to derive the non-dimensional set of modeled equations. The obtained set of equations is numerically processed via parametric continuation method (PCM). Several flow factors affecting the velocity, energy, and mass distributions are graphically discussed. It has been perceived that the fluid velocity field declines with the influence of velocity power index (m), while improves with the upshot of modified Hartmann number (Q). The effect of Schmidt number and chemical reaction diminishes the concentration profile [Formula: see text]. Furthermore, the energy curve enhances with the effect of thermophoresis factor, Biot and Eckert number.

A modification of explicit time integrator scheme for unsteady power-law nanofluid flow over the moving sheets

This paper introduces an exponential time integrator scheme for solving partial differential equations in time, specifically addressing the scalar time-dependent convection-diffusion equation. The proposed second-order accurate scheme is demonstrated to be stable. It is applied to analyze the heat and mass transfer mixed convective flow of power-law nanofluid over flat and oscillatory sheets. The governing equations are transformed into a dimensionless set of partial differential equations, with the continuity equation discretized using a first-order scheme. The proposed time integrator scheme is employed in the time direction, complemented by second-order central discretization in the space direction for the momentum, energy, and nanoparticle volume fraction equations. Quantitative results indicate intriguing trends, indicating that an increase in the Prandtl number and thermophoresis parameter leads to a decrease in the local Nusselt number. This modified time integrator is a valuable tool for exploring the dynamics of unsteady power-law nanofluid flow over moving sheets across various scenarios. Its versatility extends to the examination of unstable fluid flows. This work improves engineering and technological design and operation in nanofluid dynamics. Improving numerical simulations’ precision and computational efficiency deepens our comprehension of fundamental physics, yielding helpful information for enhancing systems that rely on nanofluids.

Efficient passive GDQLL scrutinization of an advanced steady EMHD mixed convective nanofluid flow problem via Wakif–Buongiorno approach and generalized transport laws

Owing to the practical importance of nanofluids and their adjustable thermal capabilities, this study intends to develop a robust generalized differential quadrature local linearization (GDQLL) algorithm for examining realistically the heat and mass aspects of electrically conducting nanofluids during their non-Darcian laminar motion nearby a convectively heating vertical surface of an active electromagnetic actuator (i.e., Riga plate). By invoking Wakif–Buongiorno model and Oberbeck–Boussinesq approximations along with other generalized transport laws (i.e., Cattaneo–Christov and non-Fick’s laws) and Grinberg’s concept, a set of gigantic partial differential equations is stated appropriately in the sense of the boundary layer approximations for describing exhaustively the present EMHD mixed convective nonhomogeneous flow under the passive control strategy of nanoparticles within the nanofluidic medium. Operationally, the dimensionless differential forms of the governing boundary equations are derived properly by introducing reasonable mathematical adjustments into the preliminary formulation. In this case, the differential complexity of the leading differential structure is reduced to a nonlinear coupled system of ordinary differential equations, whose discrete numerical solutions are computed perfectly via a well-structured GDQLL algorithm. As foremost outcomes, it is demonstrated that the nanofluid motion and its surface thermal enhancement rate can be reinforced significantly through the thermal strengthening in the convective heating and mixed convective process as well as via the electromagnetic improvement in the driven aspect of Lorentz’s forces.

The Impact of Thermal Radiation on Mixed Convective Unsteady Nanofluid Flow in a Revolving Vertical Cone

This study investigates the effects of an unsteady mixed convection nanofluid flow in a rotating vertical cone submerged in spinning nanofluid. Our analysis considered the impacts of heat flux, chemical reactions, and thermal radiation, with the thermal and concentration Biot numbers serving as constraints at the boundary. The governing unsteady and coupled partial differential equations were solved through appropriate similarity transformations, addressing the nonlinear terms inherent in these equations. The spectral quasi-linearisation method (SQLM) was employed to solve the higher-order nonlinear differential equations. This study elucidates and assesses the impact of diverse physical constraints and parameters through the use of graphical representations. Notably, the temperature distribution of the liquefied substance was intensified as the thermal and solutal Biot numbers increased.

Analysis of mixed convective stagnation point flow of hybrid nanofluid over sheet with variable thermal conductivity and slip Conditions: A Model-Based study

This research looks at the stagnation point flow of MHD Al2O3-Cu/H2O hybrid nanofluid against a permeable, vertically extending surface that uses thermal radiation and how different models of thermal conductivity affect it. This study is unique because it looks at how changes in thermal conductivity, mixed convection, and the slip velocity of hybrid nanofluids affect the stretching surface. It also looks at how changes in temperature, skin-friction coefficient, Nusselt number, and velocity affect convective thermal boundary conditions. With the use of boundary layer approximations, the complicated system of PDEs is simplified. The dimensionality of these PDEs and the boundary conditions they include are eliminated by applying certain modifications. Combining a local non-similarity approach up to the second truncation level with MATLAB's built-in finite difference code (bvp4c), one can obtain the results of the updated model. The research demonstrates and analyzes the impact of different factors on fluid flow and heat transfer characteristics in the studied flow situations. This is done by comparing the computed data with available literature and presenting the findings in graphical form. Tables are generated to present the numerical fluctuations of the drag coefficient and Nusselt number. This study shows how important thermal conductivity is in the mixed convection of hybrid nanofluids and looks into what happens when the thermal conductivity parameter is changed. Significantly, an augmentation in this parameter results in an elevation in the temperature distribution of the hybrid nanofluid while simultaneously reducing the rate of heat transfer across various models. Furthermore, increasing the nanoparticle volume fraction parameter leads to higher temperature and Nusselt number profiles while reducing skin friction. The mixed convection parameter has a notable impact on increasing the friction coefficient on the stretched vertical surface. However, because these elements function as regulating variables, it decreases when the magnetic, mass suction, and velocity slip parameters are present. The results also demonstrate notable discrepancies in the mean Nusselt values generated by various thermal conductivity models. According to the analysis, the Hamilton-Crosser model has the lowest average Nusselt numbers, followed by the Yamada-Ota model and the Xue model, in that order.

Significance of mixed convective double diffusive MHD stagnation point flow of nanofluid over a vertical surface with heat generation

The mixed convection double-diffusive MHD flow of boundary layer nanofluids above vertical region is designed. This flow is explained near stagnation point along with heat generation. Using Buongiorno’s model, the properties of Brownian motion, thermophoresis, and diffusion of regular and cross type are included. Using appropriate similarity transformations of the local similarity technique, non-linear unstable PDEs in governing model converted to non-linear ODEs, which were then evaluated numerically by the Keller-box method (KBM) using the computational software MATLAB 2021a. Graphical analysis of possessions of parameters on the boundary layers in profiles of velocity, solute concentration, temperature and nanoparticle concentration is illustrated. The statistics of the reduced Sherwood number and the reduced Nusselt number for solute and nanoparticles in cases of assisting flow and opposing flow are added as well to the results. The fastest rate of heat transfer is achieved in a scenario with a negligible thermophoresis effect. The thermophoresis parameter and the buoyancy parameter of the regular double diffusive appear to rise rather than decrease in the nanoparticles lowered Sherwood number, while the Brownian motion parameter rises. The temperature and layer thickness for heat generation have a quite opposite effect. When the computed numerical findings are compared to earlier published work, it is discovered to be in good percentage. The need for numerous industrial applications and improvements in the efficiency and energy consumption of systems, such as cooling and heating transportation, in water heaters, nuclear reactors, optical devices, turbines, aerodynamics, and electronics, have led to the establishment of this investigation.

Effect of viscous dissipation and induced magnetic field on an unsteady mixed convective stagnation point flow of a nonhomogenous nanofluid

In the study, we investigate the numerical investigation of variable viscous dissipation and source of heat or sink in mixed convective stagnation point flow the unsteady non-homogeneous nanofluid under the induced magnetic parameter. Considering similarity conversions, the governing of fundamental boundary of layer non-linear PDEs are transformed to equations of the non-linear differential type that, under appropriate boundary conditions, are numerically solved, and the MATLAB function bvp4c is considered to solve the resulting system. The obtained results are calculated numerically for non-dimensional velocity, temperature, and volume fraction and displayed graphically. Further, numbers of Nusselt and Sherwood and local Skin of friction have been produced and displayed by graphs. A comparison with previous results obtained neglecting the new parameters has been made to show the impact of new external parametes on the phenomneon. The obtained findings agree with those introduced by others if the magnetic field and viscous dissipation are neglected. The results obtained have an important applications in diverse field as chemical engineering, agriculture, medical science, and industries.

On thermal distribution of MHD mixed convective flow of a Casson hybrid nanofluid over an exponentially stretching surface with impact of chemical reaction and ohmic heating

On thermal distribution of MHD mixed convective flow of a Casson hybrid nanofluid over an exponentially stretching surface with impact of chemical reaction and ohmic heating

Significance of coupled effects of resistive heating and perpendicular magnetic field on heat transfer process of mixed convective flow of ternary nanofluid

Significance of coupled effects of resistive heating and perpendicular magnetic field on heat transfer process of mixed convective flow of ternary nanofluid

Nanofluid Flow Past a Static Wedge with Velocity Slip Condition

Nanofluids are known for their exceptional thermophysical properties, especially their thermal conductivity, which make them ideal for a number of heat transfer applications. In this study, the mixed convection nanofluid flow past a static wedge with the presence of velocity slip condition is investigated. The problem is governed by a system of partial differential equations which then transformed into a set of nonlinear ordinary differential equations by using an appropriate similarity transformation. The transformed governing equations are then solved numerically by using MATLAB bvp4c solver. Numerical solutions obtained are presented graphically in the form of velocity and temperature profiles for different values of nanoparticles volume fraction, wedge angle and velocity slip. It is found that the increasing values of the wedge angle parameter causes the velocity of the fluid to increase whereas the temperature profile of the nanofluid decreases, additionally it observed that velocity of the fluid increase when velocity slip is increased. The findings of this study provide valuable insights into optimizing heat transfer processes in various engineering applications by leveraging the enhanced thermal properties of nanofluids and considering factors such as wedge angle and velocity slip

Mixed convective flow of nanofluid across exponential surface: A numerical assessment of the impact of Darcy-Forchheimer and nanoparticle aggregation

Improving heat transmission is a modern difficulty faced in a multitude of areas, incorporating but not limited to electronics, heat exchangers, biochemical reactors, and other similar areas. In their capacity as cutting-edge heat transfer fluids, nanofluids have the promise of becoming a useful instrument in the pursuit of greater energy transfer efficiency. So, the focus of this work is on how it is possible to enhance heat transmission by using nanofluids. Using a stretched exponentially accelerating surface, this analysis investigates the effect that nanoparticle aggregation with thermal radiation has on the nanofluid of mixed convective stagnation point flow through Darcy-Forchheimer porous surfaces. The aggregation of nanoparticles may be assessed using modified Krieger-Dougherty and Maxwell-Bruggeman models. By using the right similarity transformations, the controlling equations of this problem were turned into a numerical model that can be unraveled. Mathematica was used to resolve the issue numerically by using the shooting with Runge-Kutta (RK-IV) procedure. nanoparticles with base fluid under aggregation effect boost heat transfer performance. A diversity of parameter estimates, including the mixed convection, mass suction, solid volume fraction of nanoparticles, thermal radiation, and stretching, were used to provide solutions for heat transfer and lower skin friction coefficients, as well as velocity and temperature curves. In addition to the findings, there were graphs and tables with explanations. The increase in heat transfer rates was 6.7021% when the suction parameters were set between 2.0 to 2.5 with =0.01. When the amount of nanoparticles volume fraction went from 0% to 1% by volume, the ineptitude of heat transfer went by an average of 4.249%. Aggregation models are often favored over non-aggregation models due to their ability to provide more accurate velocity and skin fraction profiles. Because of their superior precision, they are often used in situations where accuracy is paramount.

Mixed convection simulation of TMPHN by Eringen’s micropolar rules, Tiwari–Das nanofluid model, and mass-based hybridity algorithm

In this study, a combination of the Tiwari–Das nanofluid model, the mass-based hybridity algorithm, and the Eringen micropolar rules are applied to inquire about the mixed convective flow of a thermo-micropolar hybrid nanofluid (TMPHN) over a shrinking perpendicular surface. The working fluid of the TMPHN includes two nanoparticles (alumina and copper) suspended in an aqua-base fluid. The applied methodology considers the masses of base fluid and nanoparticles as an alternative to the first and second nanoparticle volume fractions, which is named the mass-based hybridity algorithm. The transformed ODEs are solved numerically by the shooting-based bvp4c method with MATLAB software. It is significant to mention that the nonlinearity of the pertinent governing equations and the nature of the pertinent boundary conditions both contribute to the duality of similar solutions. The effects of various controlling factors on the velocity, the angular velocity, and temperature, as well as the shear stress, the gradient of micro-rotation, and heat transfer, are graphically depicted. With great confidence, the current algorithm for the modeling of thermo-micropolar hybrid nanofluid can be applied to a variety of issues. Moreover, the numerical outputs reveal that the shrinking parameter range for the occurrence of solution duality increases with the alumina mass and the Richardson number. The findings, in a comprehensive and detailed form, have been presented in the article’s body.

Instability of MHD mixed convection flow of nanofluid in porous channel with thermal radiation, chemical reaction, Dufour and Soret effects

The present paper aims to investigate a stability analysis of the mixed convection of Al2O3/water nanofluid through an anisotropic porous channel heated from below and cooled from above. The effects of the magnetic field, thermal radiation, chemical reaction, mass transfer (Soret effect) and energy transfer (Dufour effect) are taken into consideration. The equations governing the motion of the nanofluid are converted by means of hydrodynamic stability theory into a system of eigenvalue equations which is then solved numerically by the spectral collocation method. The effects of Hartmann number, thermal radiation parameter, volume fraction of nanoparticles, permeability parameter, chemical reaction parameter, Dufour and Soret number are presented and analyzed. The results showed that in presence of nanoparticles the inertia of the working fluid increases, which dampens the disturbances and thus reduces their growth. The Hartman number attenuated the amplitude of the disturbances and thus has a stabilizing effect. The permeability parameter affected the stability of the flow and its growth prevented the redistribution of disturbances within the flow, which reflected its stabilizing character. The numbers of Soret and Dufour showed an important effect on the stability of the convective mixed flow. Their growth increased the transition Reynolds number for which there was a transition to instabilities, which prevented the transition to increasingly turbulent flows. On the other hand, the increase in the chemical reaction parameter decreased the values of transition Reynolds number, thus showing that the chemical reaction maintained the instabilities.

Bioconvective flow of fourth-grade nanofluid via a stretchable porous surface with microbial activity and activation energy

The current work scrutinizes electro-magnetized mixed convective flow of radiative fourth-grade nanofluid over a stretchable surface with bioconvection mechanism, thermophoretic body force, Brownian motion and activation energy for both nanoparticles (NPs) and motile microorganisms. Also, features of viscous dissipation, fluctuating fluid viscosity, Joule heating, suction/injection, heat source/sink and convective heat-mass-microbial conditions are included in the flow model. By employing suitable dimensionless variables, the set of model equations has been transformed into non-dimensional ordinary differential equations, which are subsequently tackled using quasilinearization-based spectral collocation approach applied in overlapping grids. For different flow parameters, numerical results of flow profiles and quantities of engineering intrigue are discussed. The results reveal that the inclusion of Biot numbers for heat, mass and microbes transfer helps to enhance flow profiles along with quantities of engineering interest. The material parameters enhance the magnitude of velocity, which is also higher for the fourth-grade nanomaterial model. Better heat transfer attributes can be achieved through strong thermophoretic force, thermal radiation, heat generation, viscous dissipation and NP Brownian motion. Activation energy increases NP concentration, while a decreasing trend is notable for higher chemical reaction and NP Brownian diffusion parameters. Bioconvection parameters reduce the motile microbes concentration, while enhancing the rate of motile microbes transfer. Microbial Brownian motion and microbial reaction play a crucial role in the dynamics of microorganisms, and that is confirmed by their noticeable effect on the flow properties.

Entropy analysis of Cu-Al2O3 based hybrid and Cu based mono nanofluid flows through porous medium: A comparative study

The motive of this research article, is to present a comparative study of entropy generation for a system of MHD mixed convection non-Darcy porous medium flow of mono and hybrid nanofluids over a melting surface. Darcy–Forchheimer model for the flow through porous medium is employed to formulate the problem under consideration. The dimensional momentum and heat equations governing the flow are transformed into a non-dimensional ODEs with the help of similarity variables. The similarity solution of the dimensionless differential equation is computed with the MATLAB’s bvp4c package. The influence of various embedded parameters on the flow fields and entropy generation are examined. The study reveals that the entropy generation in Cu−Al2O3 water based hybrid nanofluid is smaller compared to that of Cu-water based mono nanofluid. The findings of the study have bearing in the fields involving oil flow filtration, crude oil production, electronic cooling equipment etc.

Analytical analyzing mixed convection flow of nanofluid in a vertical channel using python approach

This study uses analytical methods to investigate the impact of parameters on the mixed convection flow of nanofluid in a vertical channel. The research aims to explore the heat transfer characteristics of nanofluids for more efficient heat transfer in devices. The study analyzes the influence of the Reynolds, Grashof, and Prandtl numbers on nanofluid flows. It also examines the effects of temperature and nanoparticle concentration distributions on parameters such as Brownian motion (Nb), thermophoresis (Nt), and Lewis number (Le). The presence of nanoparticles significantly enhances the heat transfer characteristics in the flow problem. Reynolds number, Grashof number, and Prandtl number significantly impact flow behavior. Velocity, temperature, and nanoparticle volume fraction profile trends are thoroughly investigated and found to vary. Akbari-Ganji's method (AGM) and the homotopy perturbation method (HPM) demonstrate the potential of computational tools in analyzing nanotechnology fluid dynamics. The accuracy and reliability of the proposed analytical techniques are confirmed through comparisons with a numerical method. The novelty of this research lies in its comprehensive analysis of parameter effects on the mixed convection flow of nanofluid, the enhanced heat transfer characteristics in the presence of nanoparticles, and the unique contributions offered by the utilization of Python programming in this field. The outcomes of this study provide insights for designing and optimizing heat transfer systems using nanofluids, contributing to advancements in nanotechnology.

Stability Analysis on Mixed Convection Nanofluid Flow in a Permeable Porous Medium with Radiation and Internal Heat Generation

We investigated the mixed convection boundary layer flow over a permeable surface embedded in a porous medium, filled with a nanofluid and subjected to thermal radiation, magnetohydrodynamics (MHD) and internal heat generation. The nanofluid consists of water (H2O) as the base fluid and nanoparticles such as copper (Cu), aluminium oxide (Al2O3) and titanium dioxide (TiO2). The governing system nonlinear partial differential equations is transformed into a set of ordinary differential equations using a similarity transformation, which are then solved numerically for various parameter values. The numerical solutions are obtained using the shooting technique method and bvp4c method, via MAPLE and MATLAB, respectively. Our findings revealed that the velocity distribution decreases with the shrinking parameter, while the presence of nanoparticles enhances the respective profiles. The velocity profiles were also observed to exhibit mixed patterns influenced by magnetic, radiation, and suction parameters. Further, the solutions bifurcated into two branches prior to the shrinking parameter. A stability analysis is performed to determine the stability of the solutions between two branches. We thoroughly discussed the characteristics of the respective solutions and their stability in detail.

Entropy generation analysis for mixed convection flow of nanofluid due to vertical plate with chemical reaction effects

The analysis have been presented to observe the optimized flow of Casson nanofluid conveying the applications of external heat generation and mixed convection features. The problem is further influenced by chemical reactive species with order one. The significant of Bejan number is evaluated. A vertically moving with convective heat phenomenon endorsed the flow. The modeled problem is reflected in terms PDE’s which are further simplifies with dimensionless form. The analytical outcomes have been established with implementation of Laplace technique. The graphical impact conveying the different parameters is assessed. The insight of skin friction and Nusselt number is observed via various curves. It is observed that entropy generation enhanced due to porosity parameter and magnetic number. With increasing Casson fluid parameter, the entropy generation decrease. Moreover, the Bejan number decreases for chemical reaction constant.

Unsteady mixed convective flow of hybrid nanofluid past a rotating sphere with heat generation/absorption: an impact of shape factor

Purpose This study aims to examine the flow of unsteady mixed convective hybrid nanofluid over a rotating sphere with heat generation/absorption. The hybrid nanofluid contains different shapes of nanoparticles (copper [Cu] and aluminium oxide [Al2O3]) in the base fluid (water [H2O]). The influence of different shapes (sphere, brick, cylinder, platelets and blades) of nanoparticle in water-based hybrid nanofluid is also investigated. Design/methodology/approach To analyse the nanomaterial, the flow model is established, and in doing so, the Prandtl’s boundary layer theory is incorporated into the present model. The bvp4c approach, i.e. finite difference method, is used to find the numerical solution of differential equations that is controlling the fluid flow. The effect of relevant flow parameters on nanofluid temperature and velocity profile is demonstrated in detailed explanations using graphs and bar charts, whereas numerical results for Nusselt number and the skin’s coefficient for various form parameters are presented in tabular form. Findings The rate of heat transfer is least for spherical-shaped nanoparticle because of its smoothness, symmetricity and isotropic behaviour. The rate of heat transfer is highest for blade-shaped nanoparticles as compared to other shapes (brick, cylindrical and platelet) of nanoparticles because the blade-shaped nanoparticles causes comparatively more turbulence flow in the nanofluid than other shapes of nanoparticle. Heat generation affects the temperature distribution and, hence, the particle deposition rate. The absorption of heat extracts heat and reduce the temperature across the rotating sphere. The heat generation/absorption parameter plays an important role in establishing and maintaining the temperature around the rotating sphere. Research limitations/implications The numerical study is valid with the exception of the fluctuation in density that results in the buoyancy force and the functional axisymmetric nanofluid transport has constant thermophysical characteristics. In addition, this investigation is also constrained by the assumptions that there is no viscosity dissipation, no surface slippage and no chemically activated species. The hybrid nanofluid Al2O3–Cu/H2O is an incompressible and diluted suspension. The single-phase hybrid nanofluid model is considered in which the relative velocity of water (H2O) and hybrid nanoparticles (Al2O3–Cu) is the same and they are in a state of thermal equilibrium. Practical implications Study on convective flow across a revolving sphere has its applications found in electrolysis management, polymer deposition, medication transfer, cooling of spinning machinery segments, spin-stabilized missiles and other industrial and technical applications. Originality/value The originality of the study is to investigate the effect of shape factor on the flow of electrically conducting hybrid nanofluid past a rotating sphere with heat generation/absorption and magnetic field. The results are validated and provide extremely positive balance with the recognised articles. The results of the study provide many appealing applications that merit further study of the problem.

Mathematical investigation of nanoparticle aggregation and heat transfer on mixed convective stagnation point flow of nanofluid over extendable vertical Riga plate

The purpose of this study is to evaluate the effects that aggregation of nanoparticles has on mixed convective stagnation point flow and porous media across a permeable stretched vertical Riga plate in the occurrence of a heat source or sink for ethylene glycol-based nanofluids. It is possible to evaluate nanoparticle aggregation with modified versions of the Krieger-Dougherty and Maxwell-Bruggeman models. To obtain numerical solutions to the mathematical model of the present issue, the Runge–Kutta (RK-IV) with shooting technique in Mathematica was used. Figures in the proposed mixed convection and suction variables along a boundary surface in the stagnation point flow towards a permeable extending Riga plate identify and explain heat transfer processes and interrupted flow occurrences. By combining titania (TiO 2) nanoparticles with ethylene glycol as the base fluid, improved heat transmission is possible. The effects of different inputs on temperature and velocity profiles, skin friction coefficient, and local Nusselt number were graphically shown using tables and graphs. The heat transmission and skin friction rates both increased when the suction parameter was given larger values. Increases in both skin friction and the Nusselt number may be attributed to variations in the volume percentage of nanoparticles. Heat source parameter increased the temperature profile and reduced the Nusselt number. Aggregation models provide more accurate velocity and skin fraction profiles than homogeneous models, which is why they are more often used. The findings were confirmed by comparing the most up-to-date research with previously published results for the same situation. Results indicated that the two sets of data were consistent with one another.