Das Nanofluid Model Research Articles

Investigation of convective heat transport in a Carreau hybrid nanofluid between two stretchable rotatory disks

Abstract Hybrid nanofluids (HNFs) have outstanding energy transfer capabilities that are comparable to mono-nanofluids. Materials had appliances in obvious fields such as heat generation, micropower generation, and solar collectors. The objective of this study is to investigate the new aspects of convective heat transfer in an electrically conducting Carreau HNF situated between two parallel discs. In addition to the presumed stretchability and rotation of the discs, physical phenomena like nonlinear radiation, viscous dissipation, Joule dissipation, and heat generation and absorption are considered. The Cu and TiO2 nanoparticles dispersed in engine oil to understand the intricate phenomenon of hybridization. The Tiwari and Das nanofluid model is employed to model the governing partial differential equations (PDEs) and then simplified using boundary layer approximation. The suitable transformations of similarity variables are defined and implemented to change the set of formulated PDEs into ordinary differential equations. The reduced system is solved semi-analytically by the homotopy analysis method. The influences of involving physical parameters on the velocity and temperature are plotted with the help of graphical figures. This study brings forth a significant contribution by uncovering novel flow features that have previously remained unexplored. By addressing a well-defined problem, our research provides valuable insights into the enhancement of thermal transport, with direct implications for diverse engineering devices such as solar collectors, heat exchangers, and microelectronics.

Flow and sensitivity analysis of MHD radiative hybrid nanofluid flow across a permeable wedge with slip condition: Response surface methodology

AbstractThis current paper has been written to investigate the effect of a hybrid Tiwari and Das nanofluid model along with optimizing the flow using sensitivity analysis. Heat transfer rates and skin friction assessments were examined with the supplementation of external effects like heat source, thermal radiation, buoyancy forces, velocity slip as well as magnetic effect with spherical‐shaped nanoparticles. The mathematical modeling was formulated using a system of nonlinear PDE. Similarity transformations were implemented in the governing equations for obtaining the final set of nondimensional equations which were then solved using bvp4c code in MATLAB. The results obtained were in close agreement with published results. Some of the significant results obtained included an increase in Nusselt number by 2.26% for an increase in velocity ratio parameter () from to 0.3 along with an increase in skin friction coefficient by 0.77% with magnetic () parameter to . The heat transfer profile was augmented by 0.79% with increasing radiation parameter to while an increase of 18.84% was observed for skin friction profile values recorded for the hybrid model as compared to the base fluid model. Nusselt number reduced by 0.51% for a transition to nanofluid model from regular fluid and by 1.76% for the hybrid model compared to the nanofluid model The unblocked face‐centered central composite design (CCD) was used for analyzing the sensitivity analysis of independent, continuous input parameters on the response parameters, skin friction coefficient, and Nusselt number. The high values for , and , for Nusselt number and skin friction coefficient values, respectively, validate the ANOVA results obtained using response surface methodology (RSM). Only shows positive sensitivity for both the Nusselt number and skin friction responses. The present hybrid nanofluid model finds extensive applications in bio‐toxicity studies, manufacturing of water heaters, and forging of hot exhaust valve heads.

Numerical investigation of magnetized bioconvection and heat transfer in a cross-ternary hybrid nanofluid over a stretching cylinder

PurposeIn this study, we investigate the effects of an extended ternary hybrid Tiwari and Das nanofluid model on ethylene glycol flow, with a focus on heat transfer. Using the Cross non-Newtonian fluid model, we explore the heat transfer characteristics of this unique fluid in various applications such as pharmaceutical solvents, vaccine preservatives, and medical imaging techniques.Design/methodology/approachOur investigation reveals that the flow of this ternary hybrid nanofluid follows a laminar Cross model flow pattern, influenced by heat radiation and occurring around a stretched cylinder in a porous medium. We apply a non-similarity transformation to the nonlinear partial differential equations, converting them into non-dimensional PDEs. These equations are subsequently solved as ordinary differential equations (ODEs) using MATLAB’s bvp4c tools. In addition, the magnetic number in this study spans from 0 to 5, volume fraction of nanoparticles varies from 5% to 10%, and Prandtl number for EG as 204. This approach allows us to examine the impact of temperature on heat transfer and distribution within the fluid.FindingsGraphical depictions illustrate the effects of parameters such as the Weissenberg number, porous parameter, Schmidt number, thermal conductivity parameter, Soret number, magnetic parameter, Eckert number, Lewis number, and Peclet number on velocity, temperature, concentration, and microorganism profiles. Our results highlight the significant influence of thermal radiation and ohmic heating on heat transmission, particularly in relation to magnetic and Darcy parameters. A higher Lewis number corresponds to faster heat diffusion compared to mass diffusion, while increases in the Soret number are associated with higher concentration profiles. Additionally, rapid temperature dissipation inhibits microbial development, reducing the microbial profile.Originality/valueThe numerical analysis of skin friction coefficients and Nusselt numbers in tabular form further validates our approach. Overall, our findings demonstrate the effectiveness of our numerical technique in providing a comprehensive understanding of flow and heat transfer processes in ternary hybrid nanofluids, offering valuable insights for various practical applications.

Thermal characterization of Sutterby nanofluid flow under Riga plate: Tiwari and Das model

This investigation uses the Tiwari and Das nanofluid model to enhance the heat transfer rate in Sutterby nanofluid over a Riga plate. The effects of heat source/sink, viscosity dispersion, and mass flow for water-based fluids are also considered in this work. Sutterby fluid has been utilized to investigate the rheological features of nanofluids. The transverse Lorentz force produced by the Riga plate assists in the flow down the plate by producing an electromagnetic field. The main aim of this investigation is to evaluate the presence of two different types of nanoparticles in water, specifically silicon carbide [Formula: see text] and copper [Formula: see text]. Dimensionless variables are first used to convert the mathematical model into a non-dimensional form. The similarity approach is then used to further rewrite the non-dimensional partial differential equations into a set of similarity equations. The bvp4c function in MATLAB software provides a numerical solution to these equations. The effects on temperature and velocity profiles of many physical factors, including the Reynold number, heat source/sink, and Deborah number, have been analyzed and presented. Furthermore, using tables, a detailed analysis of the skin friction coefficient and local Nusselt numbers is conducted. The results show that convective flow is suppressed when solid nanoparticles are added to the base fluid. The velocity distribution improves as Deborah and Reynold’s numbers get a higher value. Also, the temperature field improves by incrementing exponential and thermal heat source/sink parameters.

Entropy generation analysis for convective flow of aqua Ag-CuO hybrid nanofluid adjacent to a warmed down-pointing rotating vertical cone

PurposeThis paper aims to study numerically the flow, heat transfer, and entropy generation of aqueous copper oxide-silver hybrid nanofluid over a down-pointing rotating vertical cone, with linear surface temperature (LST) and linear surface heat flux (LSHF), in the presence of a cross-magnetic field. In industrial applications, such as oil and gas plants, food industries, steel factories and nuclear packages, the real bodies may contain nonorthogonal walls and variable cross-section three-dimensional forms which this issue can clarify the importance of selective geometry in the present research.Design/methodology/approachThe mass-based scheme is accomplished for the simulation, and the entropy generation and Bejan number will be analyzed in conjunction with the aforementioned model. It has been hypothesized that two types of boundary conditions (LST and LSHF) as well as five nanoparticle shapes (sphere, brick, cylinder, platelet and disk) present a collection of crucial results. The overseeing PDEs are changed over completely to the dimensionless ODEs, and these are solved by Runge–Kutta–Fehlberg approach combined with a shooting methodology for certain values of physical parameters.FindingsSubsequent to the fantastic compromise of the computational outcomes with past reports, the outcomes are introduced to conduct the investigation of the hydrodynamics/thermal boundary layers, the skin friction and the Nusselt number, as well as entropy generation and Bejan number. A state of hybrid nanofluid, which exhibits a remarkable increase in heat transfer in comparison to the states of mono-nanofluid and regular fluid, has been found to have the highest Nusselt number; however, the skin friction values should always be taken into account and managed. The entropy generation improves with the mass of the second nanoparticle (silver), while the opposite pattern is exhibited for the Bejan number. Furthermore, the lowest value of entropy generation number belongs to the cylindrical shape of nanoparticles in the LST case. In final, a significant accomplishment of the current study is the accurate output of the mass-based scheme for an entropy analysis problem.Originality/valueTo the best of the authors’ knowledge, for the first time, in this study, a new development of natural convective flow of a hybrid nanofluid about the warmed (LST and LSHF) and down-pointing rotating vertical cone by the mass-based algorithm has been presented. The applied methodology considers the masses of base fluid (water) and nanoparticles (Ag and CuO) as an alternative to the first and second nanoparticles volume fraction. Indeed, the combination use of the Tiwari–Das nanofluid model and the mass-based hybridity algorithm for the entropy generation analysis can be the main novelty of this work.

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.

Free Convection of Viscoelastic Nanofluid Flow on a Horizontal Circular Cylinder with Constant Heat Flux

The current research study is focusing on a mathematical model for free convection boundary flow on a horizontal circular cylinder in a viscoelastic nanofluid has been constructed in this paper with boundary conditions constant heat flux. The Tiwari and Das Nanofluid model have been chosen in this analysis to investigate more nanofluid effects. A dimensionless set of partial differential equations is formed by using suitable non-dimensional variables. The transformed boundary layer equations are solved numerically using a finite difference scheme namely the Keller-box method. The effects of a few chosen factors on flow and heat transmission are investigated. Numerical solutions were obtained for the reduced skin friction coefficient, Nusselt number and Sherwood number as well as the velocity and temperature profiles. The features of the flow and heat transfer characteristics for various values of the viscoelastic parameter and nanoparticles volume fraction were analysed and discussed.

Recent Development and Future Prospective of Tiwari and Das Mathematical Model in Nanofluid Flow for Different Geometries: A Review

The rapid changes in nanotechnology over the last ten years have given scientists and engineers a lot of new things to study. The nanofluid constitutes one of the most significant advantages that has come out of all these improvements. Nanofluids, colloid suspensions of metallic and nonmetallic nanoparticles in common base fluids, are known for their astonishing ability to transfer heat. Previous research has focused on developing mathematical models and using varied geometries in nanofluids to boost heat transfer rates. However, an accurate mathematical model is another important factor that must be considered because it dramatically affects how heat flows. As a result, before using nanofluids for real-world heat transfer applications, a mathematical model should be used. This article provides a brief overview of the Tiwari and Das nanofluid models. Moreover, the effects of different geometries, nanoparticles, and their physical properties, such as viscosity, thermal conductivity, and heat capacity, as well as the role of cavities in entropy generation, are studied. The review also discusses the correlations used to predict nanofluids’ thermophysical properties. The main goal of this review was to look at the different shapes used in convective heat transfer in more detail. It is observed that aluminium and copper nanoparticles provide better heat transfer rates in the cavity using the Tiwari and the Das nanofluid model. When compared to the base fluid, the Al2O3/water nanofluid’s performance is improved by 6.09%. The inclination angle of the cavity as well as the periodic thermal boundary conditions can be used to effectively manage the parameters for heat and fluid flow inside the cavity.

Magnetized Cross tetra hybrid nanofluid passed a stenosed artery with nonuniform heat source (sink) and thermal radiation: Novel tetra hybrid Tiwari and Das nanofluid model

Researchers around the planet are attempted to explore the influence of various non-Newtonian fluids with the mono and dihybrid nanoparticles in the status of blood flowing arteries to investigate the heat transference aspect for the cure of various diseases. Current examination is created to investigate the effect of extended novel tetra hybrid Tiwari and Das nanofluid model on blood flow arteries with consideration of Cross non-Newtonian fluid model. Heat transference assessment has been taken with the insertion of impacts like heat source/sink, viscous dissipation, Joules heating as well as nonlinear thermal radiation. PDE are designed to investigate the momentum of blood flowing and temperature analysis. The governing PDE are converted into ODE with the application of similarity conversions and furthermore managed these ODE numerically with the utilization of MATLAB builtin bvp4c scheme. The obtained outcomes are studied numerically as well as graphically in the case of diverse dimensionless variables ranges between 0.5≤M≤2, 0.1≤We≤4, 0.1≤n≤1.5, 0.1≤γ≤2, 0.5≤Rd≤2, 19≤Pr≤22, 0.1≤θw≤1.5, 0.1≤Ec≤2.1, 0.5≤U≤2, 0.5≤W≤2 versus velocity, temperature, wall frictional factor and heat transition rate. From obtained outcomes it is reflected that the surface drag phenomenon weakens by the boost of a Weissenberg number and an increment variation in magneto force provides a resistance against the fluid flow. Temperature within the arteries intensifies by the advantage of a thermal radiation and viscous dissipation.

Brownian motion and thermophoresis effects in co-flowing carbon nanotubes towards a moving plate

The heat and mass transfer of carbon nanotubes based-water nanofluids flowing through a moving plate was thoroughly investigated in this numerical work. The Tiwari and Das nanofluid model, as well as the Buongiorno nanofluid model, are formulated to characterise the problem. In transforming the governing partial differential equations into a dimensionless ordinary differential equation, similarity transformations are introduced. The numerical solver bvp4c was then deployed to investigate the dimensionless differential equations. The impact of main parameters on the skin friction, Nusselt and Sherwood numbers are elucidated and thoroughly explained. Results are then compared with published works, and the outcomes are genuinely in close alliance. With the occurrence of thermophoresis Nt, Brownian motion Nb and nanoparticle volume fraction φ, the heat and mass transfer performance are outlined. The local number Nusselt seems to be decreased by higher parameters φ, Nb and Nt. Besides, the local Sherwood number is augmenting with an increase in the φ and Nb parameters and, inversely, a decreasing function with a lower Nt parameter. The results obtained from this study may lead to new knowledge and indirectly contribute to the fluid engineering industry.

A comprehensive review of nanofluids with fractional derivatives: Modeling and application

AbstractNanofluids have been widely used as a class of promising working fluids with excellent heat transfer properties. However, the theoretical research on the thermal enhancement mechanism of nanofluids is still in the preliminary stage. Fractional constitutive models provide a new powerful tool to investigate the superior mechanical and thermal properties of nanofluids owing to their advantages in depicting the memory and genetic properties of the system. Fractional nanofluid models have become one of the hot research topics in recent years as better control of flow behavior and heat transfer can be achieved by considering fractional derivatives. The existing studies have indicated that the results obtained by the fractional-order nanofluid model are more consistent with the experimental results than traditional integer-order models. The purpose of this review is to identify the advantages and applications of fractional nanofluid models. First, various definitions of fractional derivatives and correlations of flux utilized in nanofluid modeling are presented. Then, the recent researches on nanofluids with fractional derivatives are sorted and analyzed. The impacts of fractional parameters on flow behaviors and heat transfer enhancement are also highlighted according to the Buongiorno model as well as the Tiwari and Das nanofluid model with fractional operators. Finally, applications of fractional nanofluids in many emerging fields such as solar energy, seawater desalination, cancer therapy, and microfluidic devices are addressed in detail.

Heat Transport during Colloidal Mixture of Water with Al2O3-SiO2 Nanoparticles within Porous Medium: Semi-Analytical Solutions.

In recent years, energy consumption has become an essential aspect in the manufacturing industry, and low heat transfer is one of the obstacles that affect the quality of the final product. This situation can be managed by suspending nanoparticles into ordinary heat transferring fluid (the base fluid). This newly prepared colloidal suspension has better heat transport capabilities. Keeping such usage of nanofluids in mind, this research was performed to better understand the heat transport characteristics during flow analysis saturated in porous media subject to Al2O3-SiO2/water hybrid nanofluids. This flow problem was generated by a stretching/shrinking surface. The surface of the sheet was under the influence of mass suction and second-order partial slip. The boundary layer flow was formulated in a system of partial differential equations by utilizing basic conservation laws in conjunction with the Tiwari and Das nanofluid model. Then, the appropriate form of the similarity transformation was adapted to transform the model into a system of ordinary differential equations. The built-in function, i.e., the bvp4c function in the MATLAB software, solved the reduced form of the boundary layer model. The novelty of this study lay in the predicting of two different exact and numerical solutions for both the flow and temperature fields. The computed results showed that the medium porosity as well as the nanoparticle volume fraction widened the existence range of the dual solutions. In addition, the investigational output exposed the fact that the temperature fields were significantly enhanced by the higher nanoparticle volume fraction. Moreover, the outcomes of this study showed a superb correlation with existing works. The present results can be utilized in various branches of science and engineering such as the polymer industry and in the treatment of different diseases.

Magnetohydrodynamics Mixed Convection of Viscoelastic Nanofluid Past a Circular Cylinder with Constant Heat Flux

A mathematical model for viscoelastic nanofluid flow approaching a linear horizontal circular cylinder in magnetohydrodynamics (MHD) has been developed. In the analysis, the cylinder with a constant heat flux is shown with a magnetic field. In this research, we employed the Tiwari and Das Nanofluid model to learn more about the impacts of nanofluids, and sodium carboxymethyl cellulose containing copper (Cu) nanoparticles was used as the base fluid. Dimensional linear equations are converted into dimensionless expressions using the appropriate transformations. The Keller box technique approach is used to handle the governing dimensionless concerns. Investigations are conducted on how a select few parameters affect flow and heat transfer. It includes and analyses the skin friction and heat transfer coefficients. When the obtained results are compared to the available data in the limiting situation, there is a great deal of congruence. It was discovered that the viscoelastic nanofluid's velocity, temperature, skin friction, and heat transfer coefficients heavily depend on the viscosity and thermal conductivity combined with the magnetic field and nanoparticles volume fraction.

Comparative investigation of the mixed convective stagnated flow of TiO2−CuO/water−EG$TiO_2-CuO/water-EG$ hybrid nanofluids past an exponentially stretching sheet

AbstractThis study presents a comparative investigation on the steady flow and heat transfer of different hybrid nanofluids produced by an exponentially stretching sheet in the presence of mixed convection. Tiwari and Das nanofluid model has been employed. The titania () and copper oxide () nanoparticles are suspended in water, EG and a mixture of water‐EG to form , , and hybrid nanofluids. The similarity equations are obtained from the governing equations using the similarity transformation, and their solutions are obtained using the bvp4c solver available in the Matlab software. It has been perceived from the present study that the largest % enhancement in skin friction is 39.2148% at in the hybrid nanofluid /water; however, the largest % enhancement in Nusselt number is 11.6260% at in the hybrid nanofluid /EG.

Stability aspect of magnetized hybrid nanofluid with suction and injection phenomenon: Modified thermal model

Nanoparticles with ultra-high thermal efficiency and stability have dynamic applications in numerous eras of thermal sciences, including energy production, heat transmission devices, cooling and heating systems, manufacturing applications, aircraft, and solar energy, among others. This study's primary objective is to investigate the mathematical modeling using a Tiwari and Das nanofluid model, taking into account the effects of magnetic, suction/injection, and thermal radiation, as well as the stability analysis of a hybrid nanofluid containing copper (Cu) and alumina (Al2O3) nanoparticles in a water-based liquid. Using similarity transformations, self-similarity solutions of the system of governing ordinary differential equations (ODEs) were obtained, and the resulting ODEs were simulated using implementations of the three-stage Lobatto IIIa technique. The numerical results indicate that the energy characteristics such as thermal conductivity increase rapidly when copper nanomaterials are used. It is also noticed that the combination of both nano-materials results in an excellent energy enhancement. For the solution validation, novel stability performances for the obtained simulations are determined.

Boundary layer flow of micropolar nanofluid towards a permeable stretching sheet in the presence of porous medium with thermal radiation and viscous dissipation

Nanofluids are a novel new generation of fluids to improve the heat transfer capabilities of conventional heat transfer fluids. The thermo–physical properties of these fluids are very classic in comparison to common fluids. However, one of the most crucial drawbacks for classical nanofluid models is that they cannot describe a class of fluids that have certain microscopic characteristics arising from the micro–rotation and local structure of the fluid elements. In the present study, a numerical investigation has been carried out to discuss the laminar two–dimensional heat transfer flow of micropolar nanofluid through a porous medium over a stretching sheet with viscous dissipation and thermal radiation containing copper (Cu) nanoparticles and water is considered as a base fluid. The mathematical model has been formulated based on Tiwari–Das nanofluid model. The basic equations are transmitted into a set of nonlinear ordinary differential equations using similarity transformation, and then the numerical solution is evaluated by using the Runge–Kutta fourth–order procedure. The relevant results of velocity, angular velocity and temperature are shown visually and discussed quantitatively in detail. The micro–rotation parameter enhances the velocity and temperature of the fluid. The boundary parameter declines the velocity but shows the reverse effects for angular velocity. The suction parameter decreases the velocity, but the reverse impacts are seen for the injection parameter. The graphical outcomes also show that the momentum boundary layer thickness increases with the values of volume fraction and porosity. The temperature is growing due to enhancing the Eckert number and radiation parameter.

Variable viscosity effects on the flow of MHD hybrid nanofluid containing dust particles over a needle with Hall current—a Xue model exploration

This study scrutinizes the flow of engine oil-based suspended carbon nanotubes magneto-hydrodynamics (MHD) hybrid nanofluid with dust particles over a thin moving needle following the Xue model. The analysis also incorporates the effects of variable viscosity with Hall current. For heat transfer analysis, the effects of the Cattaneo–Christov theory and heat generation/absorption with thermal slip are integrated into the temperature equation. The Tiwari–Das nanofluid model is used to develop the envisioned mathematical model. Using similarity transformation, the governing equations for the flow are translated into ordinary differential equations. The bvp4c method based on Runge–Kutta is used, along with a shooting approach. Graphs are used to examine and depict the consequences of significant parameters on involved profiles. The results revealed that the temperature of the fluid and boundary layer thickness is diminished as the solid volume fraction is raised. Also, with an enhancement in the variable viscosity parameter, the velocity distribution becomes more pronounced. The results are substantiated by assessing them with an available study.

MHD flow of a nanofluid due to a nonlinear stretching/shrinking sheet with a convective boundary condition: Tiwari–Das nanofluid model

PurposeNanofluid research has piqued the interest of scientists due to its intriguing applications in nanoscience, biomedical and electrical engineering, medication delivery, biotechnology, food processing, chemotherapy and other fields. This paper aims to inspect the behavior of the mixed convection magnetohydrodynamic flow and heat transfer induced by a nonlinear stretching/shrinking sheet in a nanofluid with a convective boundary condition. Tiwari and Das mathematical nanofluid model is incorporated in the analysis.Design/methodology/approachThe mathematical model is initially transformed to a nondimensional form by using dimensionless variables. Then the nondimensional partial differential equations are further transformed to a set of similarity equations by using the similarity technique. These equations are solved numerically by the bvp4c function in MATLAB software.FindingsFor a certain range of the stretching/shrinking parameter, two solutions are obtained. The friction factor and the heat transfer rate escalate due to suction parameter with adding nanoparticles volume fraction by almost 27.15% and 0.153% for the upper branch solution, while the friction factor declines by almost 30.10% but the heat transfer rate augments by 0.145% for the lower branch solution. Furthermore, the behavior of the nanoparticle volume fractions on the heat transfer rate behaves differently in the presence of the mixed convection effect. The temperature of fluid augments with increasing Biot number for both solutions.Originality/valueThe present work considers the flow and heat transfer induced by a stretching/shrinking sheet in a nanofluid using the Tiwari–Das nanofluid model with a convective boundary condition, where the effect of the buoyancy force is taken into consideration. It is shown that two solutions are found for a certain range of the shrinking strength, while the solution is unique for the stretching case. This study is important for scientists working in the growing field of nanofluids to become familiar with the flow properties and behaviors of such nanofluids.

Thermal performance comparative analysis of nanofluid flows at an oblique stagnation point considering Xue model: a solar application

Abstract This exploration aims to study the comparison of heat transfer capabilities of two nanofluid oblique, steady stagnation-point flow combinations comprising single-walled carbon/water (SWCNHs/water) and multiwalled carbon nanotube/water (MWCNTs/water) toward a stretching surface influenced by nonlinear thermal radiation employing the Xue model. This envisaged comparison model is inimitable and still scarce in the literature. Relying on the Tiwari–Das nanofluid model, a mathematical framework is constructed. The system of partial differential equations is converted using suitable transformations into an ordinary differential system of three equations, which is evaluated numerically using the bvp4c method. The physical behavior of significant parameters and their graphical representation are thoroughly examined. The results show that the SWCNHs/water nanofluid outperforms the MWCNTs/water nanofluid. It is further witnessed that SWCNH nanoparticle contained nanofluid has considerably greater thermal radiation than MWCNT nanoparticles. The envisaged model is also validated by comparing it with a published study.

A numerical study of hybrid nanofluids near an irregular 3D surface having slips and exothermic effects

The current article presents a comprehensive investigation of MHD viscous flow of hybrid-nanofluids (Al2O3 − Ag/ water and (Al2O3 − Cu/) over a horizontally irregular 3D plane with non-uniform thickness combined with slip effects. The foremost aim of conducting this study is to enhance thermal transportation. Based on the following novelties, the subject study holds tremendous significance: i. A comparative analysis of two hybrid nanofluids with hybrid-base fluid together with slip effects ii. An exclusive study where the Tiwari and Das nanofluid model is employed combined with Fourier's heat flux model iii. Development of finite-difference code which implements the three-stage Lobatto IIIa approach for the designed problem. We have used suitable scaling transformations to convert the three-dimensional conservation equations of mass, momentum, and energy into a dimensionless system of boundary layer equations. The numerical solution of the coupled non-linear boundary layer problem is determined using the built-in finite-difference code designed to employ the three-stage Lobatto IIIa formula. A comprehensive assessment is carried out in how the velocity components, temperature, skin friction, and heat transfer rate are affected by the physical parameters of interest. The same is presented through graphs and in tabular form to offer a pictorial overview. The fluctuating trends of skin friction coefficients (x, y-directions) and Nusselt number are investigated to explore the physical landscape of the current study. The findings of this study offer a noticeable contrast to their existing counterparts.