Mixed Convection Flow Of Nanofluid Research Articles

Aligned Magnetohydrodynamics Mixed Convection on Various Base Fluids with Carbon Nanotubes over an Inclined Plate

Analytical and graphical studies are conducted on the impact of carbon nanotubes in aligned magnetohydrodynamics (MHD) mixed convection flow of nanofluid over an inclined plate. Various types of parameters are considered throughout the numerical study with a constant wall temperature. The similarity transformation was implemented to transform the partial differential governing equations into ordinary differential equations. Furthermore, the Fourth-Order Runge Kutta algorithm is built into Maple Software to solve the transformed equations. The analysis shows how various dimensionless parameters; the angle of magnetic field, the interaction of magnetic, the angle of an inclined plate, the volume fraction of nanoparticles, and mixed convection, affect velocity and temperature profiles, as well as how carbon nanotubes with various base fluids affect skin friction and the Nusselt number. As a result, for both types of carbon nanotube nanofluids, SWCNT/kerosene and MWCNT/kerosene, an increase in angle of magnetic field, interaction of magnetic, and mixed convection parameter risen the velocity profile while an increase in angle of inclined plate and volume fraction of nanoparticles enhanced the temperature profile. However, the Nusselt number and skin friction coefficients increase with increasing angle of magnetic field, interaction of magnetic, and mixed convection parameter and decrease with increasing inclined plate angle and volume fraction of nanoparticle. It was found that MWCNT transferred heat more efficiently than SWCNT

Simulation of magneto mixed convective flow and thermal behavior of hybrid nanofluid in a partially heated wavy cavity

This study is an attempt to address numerically the thermal performance of magneto mixed convection in a wavy cavity filled with Cu-Al2O3(50%–50%) hybrid nanoparticles suspended in water under the influence of magnetic field dependent viscosity. A focus is made on the nonuniform partial heating from the left. The role of geometric parameters on the thermal performance is scrutinized thoroughly by changing surface waviness of the right wall, heating location and the direction of motion of the top and bottom walls. Based on these lid motion, the analysis is conducted by considering four geometrical set up. The transformed governing Navier–Stokes equations in dimensionless form are written in stream function-vorticity and energy transport equations. These equations are solved by using an inhouse computing code written in the compact finite difference approach. This study encompasses the effects of different physical pertinent parameters such as Richardson number, Hartmann number, magnetic orientation, solid concentrations, magnetic number. Simulations show the significant enhancement of thermal performance with the increase of magnetic orientation, undulation of the waviness and solid concentration of nanoparticles while it decreases with the increase in magnetic intensity. It is also seen that Case-I (single wall motion) and Case-III (parallel wall motion) can be an optimal configuration to get the strongest heat transfer inside the partially heated wavy enclosure.

Mixed convective flow of hybrid nanofluid over a heated stretching disk with zero-mass flux using the modified Buongiorno model

In this study, the mixed convective stagnation-point flow of a Al2O3-Cu/H2O hybrid nanofluid towards a stretched disc with a convective boundary and zero mass flux condition is described with mass suction and viscous dissipation effects. The process is accomplished by using thermophoretic and Brownian motion physical phenomena. After performing a similarity transformation on the PDEs in order to convert them into an ODE system, the bvp4c solver is then employed in order to carry out a numerical solution. In the study that was described above, the flow, heat, and mass transfer characteristics were investigated with the assistance of the Buongiorno model and the Devi and Devi model. The following characteristics were brought up as points of contention: ϕ1,ϕ2,λ,S,Nt,Nb,Le,Ec,Bi and B. There is a very good consonance among the existing and antecedent results in undeniable cases, as well as a connection error of approximately 0%. The velocity and temperature profiles upsurge with the increment of the nanoparticle volume fraction and mixed convection parameter, while the velocity increases with the addition of the suction parameters. As a result of this study, we are able to estimate the flow and thermal behavior of Al2O3-Cu/H2O when the physical parameters are embedded.

Diffusion effects on mixed convective peristaltic flow of a bi-viscous Bingham nanofluid through a porous medium with convective boundary conditions

The study of heat transfer and peristaltic pumping of magnetohydrodynamic biofluids has many physiological applications, such as heart–lung machines during surgeries, dialysis, vitamin injections, and cancer treatment. Also, it has many industrial applications, such as pharmaceutical fluid production, filtration, and dispensing cosmetic/glue emulsions with no contamination. Furthermore, the bi-viscous Bingham nanofluid model is the best for several bio/industrial fluids. Therefore, the impact of Hall current, thermal radiation, and cross-diffusion on the mixed convection peristaltic pumping of a bi-viscous Bingham nanofluid in a porous medium is considered. Also, we focus on the flexibility of the walls along with the convective boundary conditions. We adopted the lubrication strategy to reduce the system’s complexity. The system of non-dimensional partial differential equations along with the pertinent boundary conditions is solved by using a regular perturbation method (RPM) for several sets of values of the dimensionless parameters. The expressions for the temperature, concentration, velocity, and heat transfer coefficient are obtained analytically. The impact of the relevant parameters on the velocity, temperature, coefficient of heat transfer, concentration, skin friction coefficient, Nusselt number, and trapping is discussed in depth with the help of graphical illustrations and tables. The results indicate that the velocity distribution is reduced with growing Darcy parameter and concentration Grashof number. Intensifying the magnetic parameter results in shrinking the trapped bolus. Decay in the heat transfer coefficient is observed for rising values of the radiation parameter. The current findings are compared with the existing studies in the literature and are found to agree very well for special cases. Moreover, the closed form solution (RPM) is compared with the numerical solution (BVC5C, MATLAB) for validation.

A Computational Scheme for Stochastic Non-Newtonian Mixed Convection Nanofluid Flow over Oscillatory Sheet

Stochastic simulations enable researchers to incorporate uncertainties beyond numerical discretization errors in computational fluid dynamics (CFD). Here, the authors provide examples of stochastic simulations of incompressible flows and numerical solutions for validating these newly emerging stochastic modeling methods. A numerical scheme is constructed for finding solutions to stochastic parabolic equations. The scheme is second-order accurate in time for the constant coefficient of the Wiener process term. The stability analysis of the scheme is also provided. The scheme is applied to the dimensionless heat and mass transfer model of mixed convective non-Newtonian nanofluid flow over oscillatory sheets. Both the deterministic and stochastic energy equations use temperature-dependent thermal conductivity. The stochastic model is more general than the deterministic model. The results are calculated for both flat and oscillatory plates. Casson parameter, mixed convective parameter, thermophoresis, Brownian motion parameter, Prandtl number, Schmidt number, and reaction rate parameter all impact the velocities, temperatures, and concentrations shown in the graphs. Under the influence of the oscillating plate, the results reveal that the concentration profile decreases with increasing Brownian motion parameters and increases with increasing thermophoresis parameters. The behavior of the velocity profile for the deterministic and stochastic models is provided, and contour plots for the stochastic model are also displayed. This article aims to provide a state-of-the-art overview of recent achievements in the field of stochastic computational fluid dynamics (SCFD) while also pointing out potential future avenues and unresolved challenges for the computational mathematics community to investigate.

Buoyancy Assisting and Opposing Mixed Convective MHD Flow of Nanofluid along a Vertical Stretching Sheet

Buoyancy Assisting and Opposing Mixed Convective MHD Flow of Nanofluid along a Vertical Stretching Sheet

Mixed Convection Nanofluid Flow using Lie Group Scaling with the Impact of MHD Radiation Thermophoresis and Brownian Motion

The present study concerns with the mixed convection nanofluid flow across a vertical wedge with Radiation, MHD, Brownian motion, thermophoresis effects using Lie Group scaling analysis. The governing set of highly nonlinear partial differential equations are non-dimensionalized through appropriate transformations and transformed into ordinary differential equations using Lie Group Scaling, which is solved numerically using Shooting method along with bvp4c scheme. The radiation heat flux approximated with the Rosseland approximation has been implemented in the flow equations. The influence of mixed convection, magnetic, Brownian motion, radiation, Lewis number and thermophoresis parameter on the flow profiles are examined. For establishing the efficiency of our adopted numerical technique, we made comparisons with the earlier published works and we found them to be in very good agreement.

Entropy Generation of CuO-Water Nanofluid in a Cavity with an Intruded Rectangular Fin

Entropy generation and heat transfer in cavities have received significant interest due to the ever-increasing demand for enhancing thermal performances in many scientific and engineering fields. In particular, nanofluids are being used increasingly in engineering applications and real-life problems, as they exhibit significantly better thermal properties than basic heat transfer fluids, for example, water, oil, or ethylene glycol. This study investigates the entropy generation and heat transfer of a nanofluid in a confined cavity with a moving top wall and a rectangular fin at the bottom. Here, a macro-homogeneous model based on a previously developed model is employed for investigating the mixed convective flow and heat transfer of CuO-water nanofluid. Various fin geometries, Rayleigh numbers, Reynolds numbers, and nanofluid concentrations have been employed. Present results indicate that the heat transfer rate can be improved, while entropy generation can be minimized using nanofluids instead of conventional heat transfer fluids.

MHD mixed convection chemically reactive nanofluid flow over a vertical plate in presence of slips and zero nanoparticle flux

The effects of slips on mixed convection nanofluid flow past a plate in the presence of first-order chemical reaction have been examined. To direct the flow, zero nanoparticle flux at the plate has been considered to advocate the rudiments missing from the plate exterior. This situation creates the replica appropriate to a variety of manufacturing divisions for submissive control of nanorudiments fraction. Using similarity transformations, the leading PDEs (partial differential equations) are reduced to odes (ordinary differential equations) and the numerical solutions of the nonlinear equations are obtained with the help of Runge–Kutta method and shooting technique. The consequences of this study have a significant impact on flow, heat and mass transport characteristics. By diminishing the width of the boundary layer, the rising velocity slip parameter causes the fluid velocity to augment while hotness reduces for rising values of velocity slip. The speed of heat transport decreases with the mounting values of thermal slip. Flow separation occurs for buoyancy-aided flow in the presence of blowing and is controlled by suction. Due to separation, significant consequences in heat and mass transport are observed. The consequences of this study expose many motivating characteristics which deserve an additional study of the problem.

NUMERICAL SOLUTION ON MIXED CONVECTION FLOW OF NANOFLUID AROUND A FINNED ANGULAR SECTOR OF HEAT SINK

The aim of this study is to investigate mixed convection flow of nanofluid around a three-dimensional (3D) finned angular sector of heat sink by means of numerical simulations. The finite-volume method is used to solve the governing equations of mass, momentum, and energy conservation. The Brownian motion of the nanoparticles in the base fluid is explicitly taken into account in the thermal conductivity model (Patel model). A parametric study is carried out to examine the effects of several key parameters on the rate of heat transfer; the angular sector apex angle, the volume fraction of suspended nanoparticles (0 ≤ φ ≤ 0.09), the Richardson number (<i>Ri</i> = <i>Gr/Re</i><sup>2</sup>), and the size of the nanoparticles diameter (5, 20, 60, and 100 nm). It is shown that for a fixed low Richardson number <i>Ri</i>, the rate of heat transfer increases with the volume fraction of the nanoparticles, as forced convection mechanism is dominated. The heat-transfer enhancement is obtained for the nanofluid water/TiO<sub>2</sub> rather than the water/Cu at higher nanoparticles volume concentration and highest Richardson number. Moreover, the Maxwell thermal conductivity model resulted in a maximum enhancement in the case of nanofluid water/TiO<sub>2</sub> than that of water/Cu, whereas the nanofluid water/ Cu gives better heat-transfer enhancement at small particles than that of water/TiO<sub>2</sub>. It is observed too that the nanoparticles' diameter does not have a significant effect on the temperature field.

Active Controls of MHD Mixed Convection Nanofluid Flow Over a Vertical Plate with Viscous Dissipation

A significant and developing area of fluid dynamics is flow control. Due to its frequent occurrence in engineering and industrial applications, it means a tiny modification of a configuration providing an ideally big engineering benefit, such as drag reduction, lift enhancement, mixing enhancement, or noise reduction. MHD Active and Passive Controls Mixed convection nanofluid flow, including buoyant forces and viscous dissipation in the presence of chemical reaction, over a vertical plate. Using self-similarity variables, the system of highly nonlinear partial differential equations is first converted to a system of ordinary differential equations. The Richardson extrapolation enhancer and the midrich algorithm are then used to solve the resulting boundary problem system. We applied realistic Prandtl numbers of 0.71, which correspond to air at a temperature of 25 °C and a single atmospheric pressure. 2.62 was chosen as the Schmidt number to reflect the diffusing chemical species of propyl benzene. When the contributions of buoyant forces, viscous dissipation, and the presence of chemical reaction are taken to be zero, existing results are compared with our numerical result to validate it. Graphs and tables were used to show the impact of different controlling parameters, and a thorough discussion followed.

Melting heat transport in a mixed convective squeeze flow of a hybrid nanofluid with interfacial nanolayer effects

AbstractThe interfacial nanolayer effect on a mixed convection flow of single wall CNT (carbon nanotube) and CuO (cupric oxide) water based hybrid nanofluid inside a squeezed channel is studied. To maintain the flow, hybrid nanofluid under consideration is either squeezed or dilated in the parallel plate channel. Melting heat condition on one side of the channel is taken. Generalized thermophysical models which include the interfacial nanolayer effects are proposed for the hybrid nanofluid. Governing equations for the flow are tackled via similarity mappings and bvp4c technique. Statistical analysis revealed a strong significance of the interfacial ratio parameters with Nusselt numbers and skin friction coefficients at both ends of the channel. In case of squeezing flow, it is interestingly noted that the melting parameter uplifted the heat transfer rate, however reverse trend prevailed for dilating flow regime. Mixed convection parameter declined the rate of heat transfer in the squeezing channel, but elevated the coefficient of skin friction.

Entropy generation in radiative magneto-hydrodynamic mixed convective flow of viscoelastic hybrid nanofluid over a spinning disk

The heat and mass relocation properties of magneto-hydrodynamic mixed convective viscoelastic hybrid nanofluid flow induced by an extending spinning disk under the effect of entropy generation, thermal radiation, convective condition, velocity, and concentration slips has been investigated in this study. For hybrid nanofluid, the amalgamation of aluminum nitride and alumina nanoparticles embedded in carboxymethyl cellulose with a volume mass concentration of 0.0%–0.4% is considered for the study. The acquired system of partial differential equations from the intended problem is translated into ordinary differential equations employing resemblance conversion and solved by the Galerkin finite element approach. The main effects of the governing constraints on the velocity field, temperature dispersion, concentration, Bejan number, entropy production, skin friction, Nusselt number, and Sherwood number were detailed and depicted in graphs and tables. The results show that snowballing in viscoelastic constraint and volume fraction of solid non-sized particles of Al2O3 and AlN can be used to control fluid flow speed. Also, it is observed from the result that an increment in the magnetic field parameter causes a decline in the velocity field. However, the increase in magnetic field constraint and volume fraction of solid non-sized particles of Al2O3 and AlN causes an upsurge in temperature distribution. Entropy generation in the system can also be regulated by using a higher volume fraction of aluminum nitride and alumina nanoparticles. This numerical and theoretical investigation is more useful in bio-viscoelastic fluids, advanced technology, and industry.

Numerical simulation for nanofluid forced/free convection in a partially heated parallelogram enclosure: Effects of wall undulation and inclined Lorentz forces

AbstractThe present study possesses the mathematical computational analysis for mixed convection nanofluid (CuO–water) flow in a lid‐driven parallelogram enclosure with corrugated walls. A partially heated source is located at the bottom corrugated wall. The remaining portions of upper and lower corrugated boundaries are adiabatic. The verticals walls are kept cold. The flow dynamic established with wall undulation and inclined Lorentz forces generate complex mathematical formulation via partial differential equations. Finite element method is implemented to get numerical interpretation of these equations. The simulation is performed against various emerging parameters and the outcomes in terms of isotherms, streamlines and line graphs. The results are recorded against various Richardson numbers , Hartman number , nanoparticles volume fraction , and amplitude of the corrugated horizontal walls . It is observed that against smaller Richardson number streamlines indicate forced convection flow while at higher Richardson number flow divert toward free convection regime. Additionally, heat transportation is maximum when magnetic field is applied in perpendicular direction as well as at maximum amplitude of wall undulations.

Chemically reactive magnetohydrodynamic mixed convective nanofluid flow inside a square porous enclosure with viscous dissipation and Ohmic heating

Chemically reactive magnetohydrodynamic mixed convective nanofluid flow inside a square porous enclosure with viscous dissipation and Ohmic heating

EDL impact on mixed magneto-convection in a vertical channel using ternary hybrid nanofluid

Electro-osmotic transportation of conducting ionic nanofluids in vertically bounded arrangements has been expansively researched due to its vast assortment of engineering and medical applications, such as soil study, fluid dialysis, chemical processing, capillary electrophoresis, planar chromatography, separation techniques, and other real interests. On that account, in the manuscript, a theoretical model is constituted to simulate the fully developed mixed convective flow of ionic ternary hybrid nanofluid persuaded by electroosmosis and magnetohydrodynamics in a long vertical non-conducting channel under linearly changing temperature on channel walls. The classical Poisson-Boltzmann equation is employed to extract the electric double layer (EDL) impact on the flow formation via Debye-Hückel linearization conjuncture. The leading partial differential equations delineating the flow are formulated based on the general laws of conservation of momentum and energy. The relevant dimensionless setup transforms the flow model to a simplified equivalent model, which is solved analytically. The new results are comprehensively examined in terms of basic flow, magnetic, and thermal characteristics for various implanted parameters via multiple graphs and tables. Graphical outcomes confessed that the magnetic field and Debye-Hückel parameters have striking impacts on the stream features. Thin EDL supports speeding up the fluid motion through the channel domain. A noteworthy result noted from the examination is that the concentration of tri-hybridized nanoparticles in pure water is an issue that effectively delays the commencement of flow instability in the channel domain under the magnetic setting. The present study’s findings may be valuable for designing electromechanical devices, nanofluidic devices, micropumps, solar energy systems, etc.

Thermal stable properties of solid hybrid nanoparticles for mixed convection flow with slip features

Following to improved thermal impact of hybrid nanomaterials, wide range applications of such materials is observed in the thermal engineering, extrusion systems, solar energy, power generation, heat transfer devices etc. The hybrid nanofluid is a modified form of nanofluid which is beneficial for improving energy transfer efficiency. In current analysis, the solid nanoparticles aluminium (phi_{{{text{Al}}_{2} {text{O}}_{3} }}) and copper (phi_{{{text{Cu}}}}) have been mixed with water to produce a new hybrid nanofluid. The investigation of a steady two-dimensional mixed convection boundary layer flow of the resultant hybrid nanofluid on a vertical exponential shrunk surface in the existence of porous, magnetic, thermal radiation, velocity, and thermal slip conditions is carried out. Exponential similarity variables are adopted to transform the nonlinear partial differential equation into a system of ordinary differential equations which has been then solved by employing the shooting method in Maple software. The obtained numerical results such as coefficient of skin friction f^{prime prime } left( 0 right), heat transfer rate - theta^{prime } left( 0 right), velocity f^{prime } left( eta right) and temperature left( {theta left( eta right)} right) distributions are presented in the form of different graphs. The results revealed that duality exists in solution when the suction parameter S ge S_{ci} in assisting flow case. Due to non-uniqueness of solutions, a temporal stability analysis needs to be performed and the result indicates that the upper branch is stable and realizable compared to the lower branch.

MHD mixed convective stagnation point flow of nanofluid past a permeable stretching sheet with nanoparticles aggregation and thermal stratification

Using a thermally stratified water-based nanofluid and a permeable stretching sheet as a simulation environment, this research examines the impact of nanoparticle aggregation on MHD mixed convective stagnation point flow. Nanoparticle aggregation is studied using two modified models: the Krieger–Dougherty and the Maxwell–Bruggeman. The present problem's governing equations were transformed into a solvable mathematical model utilizing legitimate similarity transformations, and numerical solutions were then achieved using shooting with Runge–Kutta Fehlberg (RKF) technique in Mathematica. Equilibrium point flow toward permeable stretching surface is important for the extrusion process because it produces required heat and mass transfer patterns and identifies and clarifies fragmented flow phenomena using diagrams. Nanoparticle volume fraction was shown to have an impact on the solutions' existence range, as well. Alumina and copper nanofluids have better heat transfer properties than regular fluids. The skin friction coefficients and Nusselt number, velocity, temperature profiles for many values of the different parameters were obtained. In addition, the solutions were shown in graphs and tables, and they were explained in detail. A comparison of the current study's results with previous results for a specific instance is undertaken to verify the findings, and excellent agreement between them is observed.

Unsteady mixed convective radiative nanofluid flow in the stagnation point region of a revolving sphere considering the influence of nanoparticles diameter and nanolayer

Numerous technological applications, including rotating equipment design, missile re-entry, projectile motion and fiber coating, depend on the rotational flows and heat transfer characteristics of a forced flow stream over stationary spinning bodies of revolution. In this regard, the authors have presented an analytical solution of the mixed convective, time-dependent, laminar, and incompressible MHD flow of a water-based Al2O3 nanofluid towards the stagnation region of an angularly revolving sphere. The nanofluid transport is treated as axisymmetric and possesses constant thermophysical features except for the variation in density which originates the buoyancy force. The analytical solution of this analysis has been attempted by the homotopic approach. The convergence of the homotopic approach is presented with the help of Figure. The impacts of the embedded factors on the flow profiles are presented with the help of Figures and Tables. The results showed that the velocities and thermal profiles of the water-based Al2O3 nanofluid have been significantly enhanced by the volume fraction of an Al2O3 nanoparticle. The increasing nanoparticle diameter declines the thermal scenario while the nonlinear thermal radiation parameter and ratio of the liquid and nanolayer conductivity are enhanced the thermal profiles of the water-based Al2O3 nanofluid.

Mixed Convection Nanofluid Flow with Heat Source and Chemical Reaction over an Inclined Irregular Surface.

Two-dimensional mixed convection radiative nanofluid flow along with the non-Darcy permeable medium across a wavy inclined surface are observed in the present analysis. The transformation of the plane surface from the wavy irregular surface is executed via coordinate alteration. The fluid flow has been evaluated under the outcomes of heat source, thermal radiation, and chemical reaction rate. The nonlinear system of partial differential equations is simplified into a class of dimensionless set of ordinary differential equations (ODEs) through a similarity framework, where the obtained set of ODEs are further determined by employing the computational technique parametric continuation method (PCM) via MATLAB software. The comparative assessment of the current outcomes with the earlier existing literature studies confirmed that the present findings are quite reliable, and the PCM technique is satisfactory. The effect of appropriate dimensionless flow constraints is studied versus energy, mass, and velocity profiles and listed in the form of tables and figures. It is perceived that the inclination angle and wavy surface assist to improve the flow velocity by lowering the concentration and temperature. The velocity profile enhances with the variation of the inclination angle of the wavy surface, non-Darcian term, and wavy surface term. Furthermore, the rising value of Brownian motion and thermophoresis effect diminishes the heat-transfer rate.