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Fluid flowing over a thin needle has a significant contribution in the medical industry. Titanium oxide (TiO2) and gold (Au) nanoparticles have applications such as killing bacteria and cancer cells, and composition of these nanoparticles has potential industrial applications. Thus, the present work examines the flow attributes of Au–TiO2/ethylene glycol hybrid nanofluid flowing over a thin needle. The fluid flow is exposed to a uniform magnetic field, and fluid properties (dynamic viscosity and thermal conductivity) are considered to be temperature and nanoparticle's shape dependent. In addition, the effect of quadratic convection with quadratic thermal radiation is investigated, and the process of heat transfer is explicated using Cattaneo–Christov heat flux model. The governing expressions are solved using Legendre wavelet collocation technique. The response of the involved parameters is displayed through tables and graphs. A comparison with published work is also presented, to validate the accuracy of the applied methodology. The obtained outcomes reveal that the temperature profiles of cylindrical-shaped nanoparticles are higher and blade-shaped particles are least. Moreover, the velocity of hybrid nanofluid increases with increasing the needle size. This happens because the inner part of the needle allows larger flow area, resulting in higher flow rates and velocities. [ABSTRACT FROM AUTHOR]

Stagnation point flow defines the fluid motion near the stagnation point of a solid surface and has utilization in the process of polymer extrusion, electronic gadgets cooling, nuclear reactor, etc. Furthermore, the main theme of this work is to analyze the heat transfer characteristics of stagnation point flow of Casson nanofluid over stretching sheet using induced magnetic field and Cattaneo-Christov model. The Casson fluid is a non-Newtonian fluid model; and in the current work the working fluid consists of nanoparticles of Au (Gold) and blood (Casson fluid). In the existing model, temperature of the surface depends on the distance from the stagnation point. Therefore, Darcy-Forchheimer porous model is incorporated. The solution of coupled nonlinear PDEs is obtained by bvp4c. The heat transfer and flow characteristics of Au-blood based Casson nanofluid are discussed graphically. The dual behavior is observed in the profiles of induced magnetic field with increase in the value of reciprocal magnetic Prandtl number, however the velocity outlines of Au-blood nanofluid declined. A comparison is presented with previous article and is found to be in good agreement. [ABSTRACT FROM AUTHOR]

The importance of non-Newtonian fluid (Casson fluid) in industry is increasingly appreciated. However, little is known about the flow rheology of Casson fluid flowing over a Riga plate. Thus, the purpose of this investigation is to examine the nature of entropy generation (EG) and heat transfer (HT) on Casson hybrid nanofluid flow past a Riga plate by considering the influences of magnetic field and thermal radiation. The Hamilton–Crosser (Model 1) and Xue model (Model 2) of thermal conductivity are incorporated for Casson hybrid nanofluid. The governing equations are solved by numerical methods i.e., bvp4c and shooting techniques. In the current framework, the comparative patterns for both models of temperature, velocities, EG and Bejan number are depicted due to the existing parameters. The domain of the pertinent parameters is taken as thermal radiation, 4 ≤ R a ≤ 7 ; stretching parameter, 0. 6 ≤ λ ≤ 1 ; Casson factor, 0. 5 ≤ δ ≤ 2 ; rotation parameter, 1 ≤ ℜ t ≤ 4 and Hartmann number, 2 ≤ H a ≤ 1 1. The outcomes show that the rise in volume fraction and thermal conductivity profile of Xue model (Model 2) is better than Hamilton–Crosser model (Model 1). Moreover, EG profiles are escalated with augmentation in values of Hartmann number and stretching parameter for both models. The results of the study are useful for predicting the rheology of right fluid, while it also assists in safeguarding the boundary layer (BL) separation, along with establishing a parallel force to the surface in assisting the domain of science and technology. Mathematical model addressing the three-dimensional flow of Casson hybrid nanofluid over a Riga plate subject to viscous dissipation and linear thermal radiation was investigated. The solution to the governing equations are obtained through two numerical schemes, (i) shooting method and (ii) bvp4c. Effect of the active parameters on entropy generation is discussed through graphs and it was observed that for increasing value of both Hartmann number and stretching parameter the profiles of entropy generation increases. [ABSTRACT FROM AUTHOR]

In the era of nanotechnology and advanced manufacturing, many industrial applications involve the flow control over the rotating disk. Rotating machineries, computer storage devices, dynamic filtration processes, gas turbine engines, bio inspired electro-catalysis processes are a few of them. Considering the wide applications of flow over rotating permeable disks, this paper presents the investigation of flow, temperature and pressure characteristics of water-based titanium oxide nanofluid with temperature dependent properties. The quadratic Boussinesq approximation is considered to incorporate the density variations due to temperature change. The numerical computation is carried out using metaheuristic based hybrid shooting technique. Temperature dependent dynamic viscosity and thermal conductivity models for nanofluid are considered and the numerical results for velocity components, pressure and temperature distributions are investigated. The investigation unveiled reduction in skin friction and heat transfer rate with increasing value of quadratic convection parameter. The suction parameter is found to be very significant in terms of increasing heat transfer rates. An 80% increase in local Nusselt number is observed for a small change in suction parameter from −1 to −1.5. [ABSTRACT FROM AUTHOR]

In this article, the combined impact of thermal radiation and suction/blowing on the MHD flow of Cu-Ag/H2O-C2H6O2 hybrid nanofluid through a stretchable surface in Darcy-Forchheimer porous medium is considered. The Cartesian coordinate system and boundary layer approximation are used in the mathematical modeling of governing equations. By using suitable transformation, the governing expressions are changed into the non-dimensional forms, which are solved employing Runge-Kutta-Fehlberg method. The physical significance of relatable parameters on flow and thermal fields are analyzed through graphs. The key outcomes include that velocity diminished for the case of suction and absence of suction/injection region, on raising the values of Forchhiemer, magnetic and porosity parameters. Moreover, for blowing region, dual behavior is noticed in velocity profiles with increase in Forchhiemer and porosity parameters. [ABSTRACT FROM AUTHOR]

Nowadays, due to the novel thermal effectiveness, a new class of fluid, named “hybrid nanofluid,” is used. It has significant applications in domestic and industrial fields. In this study, we investigated the entropy generation and heat transfer of unsteady squeezing magnetic hybrid nanofluid flow between parallel plates by considering heat source/sink and thermal radiation. In this analysis, carbon nanotubes (CNTs) (single‐walled carbon nanotube and multiwalled carbon nanotube) are considered as nanoparticles that are dispersed in water‐ethylene glycol (EG) mixtures (ie, 70%W + 30%EG and 50%W + 50% EG). For the analysis of the physical behavior of hybrid nanofluids, new models related to hybrid nanofluids are incorporated. From this study, it has been observed that as the hybrid nanofluids moved away from the surface, the entropy generation outlines accelerated with an increase in magnetic field values. Moreover, an increase in the volume fraction of CNTs, the thermal conductivity of 50%W + 50% EG + CNTs hybrid nanofluid is greater than 70% W + 30%EG + CNTs hybrid nanofluid. [ABSTRACT FROM AUTHOR]

An analysis of heat and mass transfer is carried out under the influence of chemical reaction, friction heating, and heat generation/absorption over a curved surface. The impacts of random motion attributes of nanoparticles and thermophoresis are also applied in the expressions of energy and concentration. With the help of assigned transformations, the nonlinear partial differential equations are changed to dimensionless nonlinear ordinary differential equations. Then, the numerical solution is obtained using fourth‐fifth order Runge‐Kutta‐Fehlberg method via the shooting technique. The impacts of relevant parameters on velocity, temperature, and concentration are depicted through graphs and tables. The results illustrate that the lowest concentration distribution of nanofluid is related to the higher value of chemical reaction parameter. Moreover, it is found that thermophoresis and Brownian motion parameters have a propensity to increase the temperature profile while curvature parameter decreases the velocity profile. Also, velocity and temperature fields show a similar behavior for the increasing values of volume fraction of the nanoparticles, while a reverse trend is observed in the concentration profile under the same condition. To authenticate the results of the current study, the obtained data were compared with previously published data. [ABSTRACT FROM AUTHOR]

Investigation of heat transfer effect on Cu-water nanofluid flow past a stretching cylinder is focused in the recent article. The numerical method of nonlinear known as RKF 4–5th has been taken into account along with shooting process to obtain the solution of required ODEs with supplementary boundary conditions. The influence of thermal radiation parameter on non-dimensional skin friction and Nusselt number along with convection parameter, solid particle volume fraction and heat generation/absorption parameter are represented in the tabular and graphical way. The volume fraction of nanofluid is considered as 0–6% with an increment of 2%. The thermal radiation parameter lies in the domain of [ 0.3 , 5 ] . Moreover, the values of porosity parameter ( λ ) and heat generation/absorption parameter ( Q ) are varied as 0.5 ⩽ λ ⩽ 2.5 and - 2 ⩽ Q ⩽ 2 , respectively. The data of authors declared that augmentation is perceived in temperature curves with the volume fraction of solid particles; moreover, momentum boundary layer depreciates with boost in volume fraction parameter of copper (Cu) particles. The obtained data are distinguished with earlier study and admirable agreement has been noted. [ABSTRACT FROM AUTHOR]

The purpose of present study is to identify the effects of viscous dissipation and suction/injection on MHD flow of a nanofluid past a wedge with convective surface in the appearance of slip flow and porous medium. The basic non-linear PDEs of flow and energy are altered into a set of non-linear ODEs using auxiliary similarity transformations. The system of equations together with coupled boundary conditions have been solved numerically by applying Runge-Kutta-Fehlberg procedure via shooting scheme. The influence of relevant parameters on non-dimensional velocity and temperature profiles are depicted graphically and investigated in detail. The results elucidate that as enhance in the Eckert number, the skin friction coefficient increases, while heat transfer rate decreases. The outcomes also specify that thermal boundary layer thickness declines with an increase in suction parameter. Moreover, it is accelerated with augment in injection parameter. The results are analogized with the study published earlier and it creates a fine concord. [ABSTRACT FROM AUTHOR]