Nanofluid Flow Research Articles

Thermal performance of mixed convective radiative peristaltic flow of Bingham nanofluid

The significance of peristaltic phenomena has generated substantial interest within the fields of biological and biomedical engineering. Therefore, the present study deals with magnetohydrodynamics (MHD) peristaltic flow of Bingham nanofluid in a channel. Here the channel walls are symmetric and elastic in nature. Velocity slip, heat and mass convective conditions are enforced on channel walls. The aspects of dissipation, Joule heating and mixed convection is analyzed. Thermal transport included the features of thermal radiation, Brownian and thermophoresis motion. Analysis and modelling are investigated in the presence of the phenomenon heat generation and absorption. The analysis has been wrapped up under the assumptions of a long wavelength and a low Reynolds number. Numerical techniques are implemented for finding the solutions of governing differential system. Results for velocity, concentration, thermal field, rate of heat transfer, skin friction coefficient, Nusselt number and Sherwood number are analyzed subject to pertinent parameters. The study reveals that velocity is enhanced via both thermal Grashof number and velocity slip parameter. Temperature shows opposite behavior against radiation and Brinkman number. Rate of heat transfer enhances for larger values Brownian motion and Hartman parameters. This study's practical applications include the use of peristaltic pumps for drug delivery in the pharmaceutical and chemical industries.

Numerical Study of Three-Dimensional Models of Single- and Two-Phase Nanofluid Flow through Corrugated Channels

This study delves into computational fluid dynamics (CFDs) predictions for SiO2–water nanofluids, meticulously examining both single-phase and two-phase models. Employing the finite volume approach, we tackled the three-dimensional partial differential equations governing the turbulent mixed convection flow in a horizontally corrugated channel with uniform heat flux. The study encompasses two nanoparticle volume concentrations and five Reynolds numbers (10,000, 15,000, 20,000, 25,000, and 30,000) to unravel these intricate dynamics. Despite previous research on the mixed convection of nanofluids using both single-phase and two-phase models, our work stands out as the inaugural systematic comparison of their predictions for turbulent mixed convection flow through this corrugated channel, considering the influences of temperature-dependent properties and hydrodynamic characteristics. The results reveal distinct variations in thermal fields between the two-phase and single-phase models, with negligible differences in hydrodynamic fields. Notably, the forecasts generated by three two-phase models—Volume of Fluid (VOF), Eulerian Mixture Model (EMM), and Eulerian Eulerian Model (EEM)—demonstrate remarkable similarity in the average Nusselt number, which are 24% higher than the single-phase model (SPM). For low nanoparticle volume fractions, the average Nusselt number predicted by the two-phase models closely aligns with that of the single-phase model. However, as the volume fraction increases, differences emerge, especially at higher Reynolds numbers. In other words, as the volume fraction of the nanoparticles increases, the nanofluid flow becomes a multi-phase problem, as depicted by the findings of this study.

Evaluation of nanoparticle shape factor on a laminar forced convective heat transfer characteristics of various nanofluids flow in a tube using single-phase numerical model

Nanotechnology is advantageous in improving thermophysical properties and enhancing heat transfer rate compared with conventional fluids due to their superior thermophysical properties. These properties vary with many parameters such as concentration and shape. In this study, the effect of nanoparticles shape is numerically explored on heat transfer performance under a laminar flow regime (Re=500 and 2000) through the smooth tube. Heat transfer enhancement capability of the nanoparticle shapes with targeted reference to average Nusselt number, average Darcy friction factor, pumping power, and performance evaluation criterion have been investigated. Three types of nanofluids (Fe3O4/water, Al2O3/water, and GO/water) with various nanoparticle shapes (brick, cylindrical, platelet, and spherical) and different nanoparticle volume fractions (φ=1.0, 2.0, 3.0, and 4.0%) have been used as heat transfer fluid in analyzes. Numerical results show that heat transfer performance was greatly influenced by changing nanoparticle shapes. The highest average Nusselt number was obtained for GO/water nanofluid with platelet nanoparticle shape and φ=4.0%. Compared to water, Fe3O4/water, and Al2O3/water, the average Nusselt number in GO/water increased by 64.34%, 54.02%, and 43.41%, respectively. The highest performance evaluaton criterionwas obtained for the GO-water nanofluid with platelet nanoparticle shape at Re=2000. On the other hand, it is found that the Fe3O4/water nanofluid with platelets nanoparticle shape causes the highest pumping power compared with other analyzed nanofluids.

Pulsating magnetohydrodynamic hybrid nanofluid flow with thermal radiation, viscous dissipation, and entropy generation: Application to bio-nanomedicine

The aim of this investigation is to explore the flow phenomena in two distinct hybrid nanofluids (with micropolar fluid as the base fluid) undergoing hydromagnetic pulsation between two vertical walls, accompanied by entropy generation. This study also explores the unique heat transfer characteristics of F e 3 O 4 − Ti O 2 and A l 2 O 3 − MgO hybrid nanofluids, with the effects of Ohmic heating, thermal radiation, and viscous dissipation. The goal of using hybrid nanofluids is to improve the performance of biological systems such as nano-drug delivery in arteries, magnetic bio-separation, artificial kidneys, pressure surges, magnetofection agents, biomedical engineering, cancer treatments, and brain tumor treatment. The governing partial differential equations are transformed into a system of ordinary differential equations, which are then solved numerically by a shooting technique with a fourth-order Runge-Kutta method using a bvp4c MATLAB solver. Graphical explanations are provided for the flow variables such as the velocity, the microrotation, the temperature, the entropy generation, and the Bejan number. The heat transfer rate is an increasing function of the thermal radiation parameter; when the thermal radiation parameter increases from 1 to 3 the increases in the heat transfer rates in micropolar fluid (the base fluid), first hybrid nanofluid ( F e 3 O 4 − Ti O 2 ), and second hybrid nanofluid ( A l 2 O 3 − MgO ) are respectively 55%, 51%, and 43.86%. However, while the heat transfer rate (the Nusselt number) is a diminishing function of the Hartmann number. Further, the outcomes reveal that the hybrid nanofluids with emerging physical effects are helpful to treat cancer patients, recovering the damaged tissues and cells in arteries, and various medical-related procedures.

Heat transfer scrutiny in EMHD ternary hybrid nanofluid flow between convergent/divergent channels with stretchable walls

ABSTRACT The main interest of the existing work is the numerical and analytical exploration of heat transference on MHD Jeffery-Hamel flowing of a ternary hybrid nanofluid with an external magnetized force and electrical field (EMHD). The two walls of the system are also taken to be stretchable (shrinkable). Mixture base fluid (ethylene glycol-water 50%–50%) hybrid nanofluid containing MoS2, Al2O3, and TiO2 as the nanoparticles are contemplated. The modeled partial differential equations were converted to nonlinearly ordinary differential equations by applying the similarity transformations and resolved analytically by utilizing the Duan – Rach Approach (DRA). The present results in particular cases are compared to results obtained by the HAM (homotopy analysis methodology)-based Mathematica BVPh 2.0 code and by the Runge-Kutta Fehlberg 4th–5th order (RKF-45) for validation. The effect of varied factors on non-dimensional rapidity, temperature profiles, frictional force factor, and Nusselt quantity has been examined and explained via tabular and graphical outcomes. Certainly, new modeling and reliable analytic treatment via the DRA approach for the ternary hybrid nanofluid is a sizable accomplishment of the current analysis.

On the augmentation of heat transfer with hybrid nanofluid containing microorganisms on flat plate under thermal radiation, using mixtures models

In this study, an investigation of a hybrid nanofluid flow across a stretched flat sheet is presented. On a flat, flexible surface, a water-based hybrid nanoliquid is propagating in a horizontal orientation, while a strong magnetic field is located along an upright direction to the flow. The flow is incompressible, magnetically influenced and electrically conducting. The aluminum – and graphene (Go) are dispersed in the working fluid. The main interest of this exploration corresponds to microorganism diffusivity with Brownian motion and thermophoresis diffusion for two different nanoparticles, which are modeled in a different set of equations. The flow and heat-mass transfer equations are constructed using Buongiorno's nanofluid model and hybrid nanofluid volumetric friction. The Runge–Kutta–Fehlberg procedure combined with the shooting procedure is employed to find the numerical solutions of governing equations. The results reveal that increasing magnetic force drags down the frictional coefficient. The highest energy transfer 19% was recorded with 1% of Al2O3 and 5% of Go. Higher Peclet number detracts the motile density. The faster heat transmission was observed by thermal radiation. The volumetric percentage of nanomaterials was influenced by both types of Brownian characteristics. The novel parameter [Formula: see text] influences the Sherwood and Nusselt numbers. When compared to Go, the temperature profile and the heat transmission rate for the second particle Al2O3 are higher. The Sherwood number declines with a rise in the thermophoresis parameter and rises with an improvement in the Lewis number and Brownian motion. Effect of [Formula: see text] and [Formula: see text] on mass transport rate are encouraging.

Shape matters: Convection and entropy generation in magneto-hydrodynamic nanofluid flow in constraint-based analogous annular thermal systems

This work analyzes the performance of annular thermal systems of distinct geometries to understand their shape impacts using a novel constraint-based methodology. This research fills the gap in the literature by analyzing the geometrical shape impact of magnetohydrodynamic CuO/water nanofluid flow on fluid flow, heat transfer, and thermodynamic irreversibility. Through computational simulations, the outcome results demonstrate that the circular annuli (Case 1 and Case 2) outperform the analogous square system in terms of fluid velocity, heat transfer, and irreversibility. The analysis is carried out for a range of Rayleigh numbers (Ra = 103 to 106), nanoparticle concentrations (ζ = 0 to 4%), magnetic fields (Ha = 0 to 100), and magnetic field inclinations (γ = 0° to 180°). Additionally, a significant improvement in heat transfer is observed by augmenting nanoparticles of the working fluid, while the magnetic field intensity plays a crucial role in controlling fluid flow and heat transfer. The study provides valuable insights into how various parameters affect the nanofluidic heat and flow characteristics of equivalent annular geometries and contributes to the development of more efficient and effective designs of thermal systems. The novelty of the study lies in its comprehensive approach in the use of a constraint-based methodology that matches the flow areas or cooling lengths while maintaining the same heating length to analyze the impact of geometric shapes on heat transport and accompanying irreversibility during MHD nanofluid flow. Furthermore, the energy-flux vectors are utilized to delve into the insights. The maximum value of heat transfer noted for Case 1 and Case 2 is approximately 7% and 11%, respectively, compared to the square annulus (Base Case). The inclusion of nanoparticles in the carrier fluid causes a significant enhancement in heat transfer by up to 11%, compared to pure fluid (ζ = 0).

Squeezing MHD Flow of Sodium Alginate-Based Casson Hybrid Nanofluid with Soret and Dufour Effects

Ultrahigh-performance cooling is one of the essential requirements in the industrial technology. Hence, the new heat transfer fluid, hybrid nanofluid is introduced to increase the thermal conductivity of fluid and investigated with various physical parameters. The unsteady magnetohydrodynamics (MHD) flow of Casson hybrid nanofluid through two surfaces in a permeable medium with chemical reaction are explored. The hybrid nanoparticles of Alumina and Copper is dispersed in the base fluid of sodium alginate . The discretize equations are solved using similarity transformation and Keller-box methods. The comparison of the current results with the published results for validation is conducted and discovered in proper agreement. The impacts of squeeze, magnetic, porous media, chemical reaction, heat sink/source, and Soret and Dufour on behaviour and physical quantities of flow are discussed. The graphical results show the squeeze of two surfaces accelerates the fluid velocity near the upper plate region. Further, the velocity slowing down when and increases, and it elevates as and rises in the middle of channel. The increment of heat transfer rate and temperature of fluid is shown for increasing Ec, y and Du, and the opposite behaviour is discovered with raise in. The fluid concentration decreases and the mass transfer rate enhances for rising Sr. The concentration enhance and rate of mass transfer reduce with the constructive chemical reaction, whereas contrary effects is shown for destructive chemical reaction.

A Numerical Investigation of the MHD Ternary Hybrid Nanofluid (Cu-Al2O3-TiO2/H2O) Past a Vertically Stretching Cylinder in a Porous Medium with Thermal Stratification

This study focuses on examining the impact of thermal stratification on the magnetohydrodynamics (MHD) flow of water-based nano, hybrid, and ternary hybrid nanofluids past a vertically stretching cylinder in a porous medium. The nanoparticles Cu, Al2O3, and TiO2 are suspended in a base fluid H2O, leading to the formation of a ternary hybrid nanofluid Cu-Al2O3-TiO2 /H2O. The numerical results are calculated with the 3-stage Lobatto IIIa approach, specifically implemented by Bvp4c in MATLAB. The impacts of various parameters are visually depicted through graphs and quantitatively represented in tables. The velocity and temperature of the ternary hybrid nanofluid are lowered by the thermal stratification parameter compared to when there is no stratification. The ternary hybrid nanofluid has a higher heat transfer rate than the hybrid nanofluid, and the hybrid nanofluid has a higher heat transfer rate than ordinary nanofluids.

New YAC time-fractional derivative approach for water-based hydromagnetic chemically reacting radiative flow of nanofluid with copper nanoparticles past an upright plate

The current article utilizes the novel application of the Yang-Abdel-Cattani (YAC) fractional derivative to analyze the Casson nanofluid flow. Water nanofluid suspended with copper nanoparticles is considered in the flow phenomenon. Primarily, the dimensionless governing equations are converted to a fractional model by using a new description of fractional derivative, i.e. YAC fractional derivative. These fractional equations are then transformed and solved using the Laplace method. Finally, the solutions of these transformed equations are obtained in terms of a series of Prabhakar functions. The comparative results for Newtonian and non-Newtonian fluids are obtained using the analytical solutions and presented in the form of graphs. The effect of the chemical reaction, Casson parameter, radiation parameter, orders of the time-fractional derivative, and magnetic strength on velocity, temperature, and concentration fields is investigated. The fluid behavior of both Newtonian and Casson fluids is analyzed and presented in the form of graphs. Fluid temperature is enhanced by 5.22% with the use of copper nanoparticles with a 4% volume fraction. With the advancement of chemical reaction, the velocity and concentration of the nanofluid are observed to be decreasing.

Thermohydraulic analysis of nanofluid flow in tubular heat exchangers with multi-blade turbulators: The adverse effects

Based on the significance of heat transfer in tubular flows, various methods of heat transfer enhancement have been developed by scholars. The use of turbulator inserts like twisted tapes is widely discussed and suggested by researchers, and many studies have concentrated on the positive influence of these devices. However, the question is whether these devices always positively impact heat transfer and fluid flow. In this study, efforts were made to find possible adverse impacts of using twisted tapes on the average Nusselt number (Nu), friction factor (f), flow behavior, and performance evaluation criterion (PEC) of water-titania nanofluid. Three-dimensional (3D) numerical methods were used to assess a combination of three different configurations of 156 cases with/without turbulators with different numbers of blades and pitch ratios (PR). Results suggest that at Reynolds number (Re) = 4000, 6000, and 8000, only 25 %, 25 %, and 22.9 % of the examined cases led to PEC values over 1. Based on the results, while twisted tapes raised the Nu by up to 65.1 %, the f can be increased by up to more than six times. Furthermore, streamlines and velocity magnitude contours were employed to discuss the fluid flow behavior in the presence of the turbulators. According to the findings, while with the best turbulator, the PEC value was increased by only 6.3 %, some of the turbulators reduced this parameter by up to 11.8 %, which is more severe. The worst performance was observed with the Case C (three-bladed) turbulator at a PR value of 11, which reduced the PEC by 11.8 %.

Optimizing heat transfer rate with sensitivity analysis on nonlinear radiative hydromagnetic hybrid nanofluid flow considering catalytic effects and slip condition: Hamilton–Crosser and Yamada–Ota modelling

AbstractIn current investigation the optimization of heat transportation rate in a nonlinear radiative buoyancy‐driven hydromagnetic carbon nanotube (CNT) hybrid nanofluid flow is analysed. The proposed catalytic effects and slip condition is accounted for the real‐world complexities of the system. The Hamilton–Crosser (HC) and Yamada–Ota (YO) models are employed to characterize the behaviour of the nanofluid. The primary objective is to enhance the heat transmission rate, which is crucial for various engineering applications such as thermal management, energy systems and so forth. To achieve this, sensitivity analysis is performed to identify the most influential parameters affecting heat transfer in the system. By understanding the sensitivity of these parameters, the performance of the system can be improvised. The study focuses on the interplay between key factors including radiative heat transfer, buoyancy‐driven flow, magnetic field influence, catalytic effects, and slip condition. The presence of CNTs in the nanofluid adds another dimension to the complexity of the system that explores the effects of varying the concentration and size of CNTs on the heat transfer rate. By utilizing advanced mathematical modelling and numerical simulations, the performance of the system under different scenarios and identify the optimal conditions for maximizing heat transfer rate is evaluated. The findings of this research provide valuable insights into the design and optimization of heat transfer systems involving nanofluids with nonlinear radiative and hydromagnetic effects. The observation shows that, irrespective to single wall and multi wall CNT nanoparticles the fluid velocity attenuates significantly whereas it favours in enhancing the fluid temperature. Further, the comparative analysis reveals that the heat transfer augments in the case of HC model than that of YO model.

Lie group analysis on EMHD Jeffrey nanofluid flow with exponential heat source: Heat transfer optimization using RSM

The present research examines the behavior of a Jeffrey nanofluid flow across a stretching sheet under the effect of electric and magnetic fields. It comprises the Buongiorno model as well as an exponential heat source. The impact of chemical reaction has also been taken into consideration. While assuming no mass flux, the study considers boundary conditions for thermal convection and velocity slip. Lie group transformations are employed to transform the set of governing equations into a dimensionless system and later simulated using the finite difference scheme. It is found that the velocity profile rises as the Deborah number is enhanced whereas the ratio of relaxation to retardation time parameter has an inverse effect on the velocity profile. It is noted that per unit change in the Deborah number descends the drag coefficient by 31.29%. In this study, the response surface methodology and sensitivity analysis have been conducted by choosing heat transport as the dependent variable and the electric-field parameter ( 0.01 ≤ E ≤ 0.03 ) , exponential heat source parameter ( 0.02 ≤ Qe ≤ 0.06 ) , and Biot number ( 0.15 ≤ Bi ≤ 0.25 ) as the independent variables. The Nusselt number escalates when the Bi number is increased and drops as the E values are raised. In the instance of the Biot number, the Nusselt number exhibits the maximum sensitivity.

Impact of Aluminum Oxide & Silicon Dioxide on Nanofluid Flow Over a Stretching Sheet with Heat Transfer: Analytical Solution

A stretchable surface is one of the products features that numerous industrial and engineering field has been taken into consideration due to of its benefit. However, most of the fluid mechanic simulation for stretchable surface has been solved numerically and there is very limited theoretical study discovering this problem. Therefore, the present study investigated the convective Casson nanofluid flow and heat transfer over a linear stretching sheet. The aluminum oxide and silicon dioxide are considered. The analytical resolution of the governing problem yields velocity and temperature solutions using the Laplace transform method. Graphical representation illustrates how nanoparticle volume fraction affects velocity and temperature distribution profiles. Higher nanoparticle volume fractions slow down nanofluid flow and elevate temperature profiles. This investigation establishes a robust foundation for future research utilizing numerical methods.

Mixed bioconvection of nanofluid of oxytactic bacteria through a porous cavity with inlet and outlet under periodic magnetic field using artificial intelligence based on LightGBM algorithm

The comprehension of microorganisms’ responses to magnetic field and fluid motion offers potential for the advancement of targeted drug delivery systems or medical interventions reliant on biological fluids. In this paper, the mixed bioconvection flow of nanofluid of oxytactic bacteria has been investigated through a porous cavity with inlet and outlet ports under the impact of periodic magnetic field. All the walls of the cavity are fixed at the constant high temperature. The proposed problem has been modeled first and then simulated using the finite element method. The computed computational fluid dynamics results have been analyzed for the several important controlling parameters. It is observed that there is at least 65% increment on heat transfer between the lowest and highest Peclet numbers. Further, regression analysis was conducted using the LightGBM algorithm. Careful parameter tuning was performed to avoid overfitting, ensuring that the model did not memorize the training data. According to the R2 values used for regression analysis, in the 18 datasets used for the performance metric comparison of the artificial intelligence model, a total of 18 targets were tried to be predicted for different Richardson number (0.1, 1, and 10) and Lewis Number (0.1, 1, and 10) values for each motile microorganisms, temperature and oxygen concentration values specified in the datasets, and a minimum accuracy of 95% and a maximum accuracy of 98% were obtained. These findings demonstrate the capability of the LightGBM algorithm to accurately predict the target variable within a high range of accuracy for the given datasets.

Thompson and Troian slip effects on ternary hybrid nanofluid flow over a permeable plate with chemical reaction

This study seeks to elucidate the electromagnetic hydro-thermal aspects of ternary hybrid nanofluid (THNF) (MoS2-SiO2-GO/water) flow over a permeable plate in the presence of Thomson and Troian slip, suction/blowing, and chemical reaction. Through the utilization of similarity transformations, the nonlinear partial differential equations (PDEs) representing the conservation of mass, momentum, energy, and concentration, are converted into ordinary differential equations (ODEs). The subsequent step involves solving these ODEs utilizing the bvp4c technique in MATLAB. The detailed graphical representations precisely elucidate the action of diverse parameters, such as Hartmann number, electric parameter, velocity slip parameter, Lewis number, critical shear rate, suction/blowing, thermophoresis, and Brownian motion parameter on the velocity, thermal, and concentration profiles. The momentum and temperature distributions respond oppositely to the parameters Hartmann number, electric parameter, and suction/blowing. Also, the absolute values of Nusselt and Sherwood numbers increase with elevated critical shear rate, velocity slip, and suction/blowing parameter but decrease with higher Lewis number and chemical reaction parameter. Moreover, adjusting the velocity slip parameter from 0.2 to 0.6 results in a 24.14% decrease in the skin friction coefficient and a 16.79% increase in the local Nusselt number.

A Stochastic Numerical Approach to Study Stagnation Point Carreau Nanofluid Flow Impacted by Thermal Radiation and Activation Energy

A Stochastic Numerical Approach to Study Stagnation Point Carreau Nanofluid Flow Impacted by Thermal Radiation and Activation Energy

Hybrid nanofluids flow over a Riga plate surrounded by a variable porous medium for heat transfer optimization

Enhancing the heat transfer rate in hybrid nanofluids is significantly aided by a porous medium. The nanofluid’s heat transfer to the surrounding medium is more efficient due to the presence of a porous medium. The porous space also provides additional surface contact points for heat exchange and an intricate network of interconnected pores. This article elaborates on the incorporation of single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs) into water to perform hybrid nanofluids. The flow is considered over a Riga plate surrounded by a variable porous space. Various applications, including thermal management systems, microelectronics cooling, and energy conversion devices, benefit greatly from the study of hybrid nanofluid flow on a Riga plate. The similarity equations of the flow problem are easily tackled with the homotopy analysis method (HAM) built on fundamental homotopy mapping. Furthermore, with the increments in paramount parameters, the skin friction coefficient and heat transfer rate are remarkably meliorated under a higher modified Hartmann number. All reverberations are illustrated in graphs and Tables. From the obtained results it is observed that flow control capabilities are enabled by the variations in permeability in the case of hybrid nanofluids. It is also observed that hybrid nanofluids are more capable to enhance the thermal capabilities of the traditional fluids as compared to the mano nanofluids.

Exploring the influence of nanolayer morphology on magnetized tri-hybrid nanofluid flow using artificial neural networks and Levenberg–Marquardt optimization

This study investigates the impact of morphological nanolayers on the thermal conductivity of magnetized tri-hybrid nanofluid flow using artificial neural networks (ANNs) employing the Levenberg–Marquardt (LM-ANN) scheme. Nonlinear partial differential equations (PDEs) are transformed into nonlinear ordinary differential equations (ODEs) using similarity variables. A dataset covering various parameters such as nanolayer thickness, particle radius, magnetic parameter, expansion/contraction ratio, Schmidt number, volume fraction, and Prandtl number is generated using the Bvp5c numerical algorithm. LM-ANN is then used for testing, training, and validation to analyze approximate solutions for individual cases. Histogram analysis, mean square error (MSE), and regression investigations validate the LM-ANN. The proposed approach closely aligns with suggested and reference findings, showing an accuracy level within 10−10 range. Increasing nanolayer thickness leads to higher effective thermal conductivity. The Nusselt number increases notably with higher hybrid nanoparticle volume fraction. Laminar shape consistently exhibits superior heat transfer performance compared to other shapes. Increasing nanoparticle volume fraction enhances the Nusselt number and reduces skin friction coefficients (SFC). Industry recommendations include integrating nanolayer technologies for improved thermal efficiency.

Hybrid Nanofluids Flow over a Vertical Cylinder with Heat Source/Sink and Prescribed Surface Heat Flux

This work presents the steady mixed convection in Al2O3-Cu/water hybrid nanofluids along a vertically stretching/shrinking cylinder with the prescribed surface heat flux and the effects of heat source/sink. The governing hybrid nanofluids model was simplified using a similarity transformation. The bvp4c solver in MATLAB software is used to solve the hybrid nanofluids flow problem numerically. It is observed that two outcomes are feasible for the assisting and opposing flow regions as well as stretching and shrinking cases . Besides that, the effects of the dimensionless parameters are analyzed graphically and tabularly. In particular, the critical point is reduced by 3% when the curvature parameter goes from 0 to 0.1 and from 0.1 to 0.2 when the cylinder is stretched. This means that the higher curvature parameter could delay the process of separating the boundary layer. It is noted that the positive heat source will decrease the fluid motions and reduce the shear stress on the surface. Moreover, Al2O3-Cu/water hybrid nanofluids have better performance in heat transfer and velocity of fluid flow than Al2O3/water nanofluids.