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Nanofluids are utilized in cancer therapy to boost therapeutic effectiveness and prevent adverse reactions. These nanoparticles are delivered to the cancerous tissues under the influence of radiation through the blood vessels. In the current study, the propagation of nanoparticles within the blood in a divergent/convergent vertical channel with flexible boundaries is elaborated computationally. The base fluid (Carreau fluid model) is speculated to be blood, whereas nanofluid is believed to be an iron oxide–blood mixture. Because of its shear thinning or shear thickening features, the Carreau fluid model more precisely depicts the rheological characteristics of blood. The arterial section is considered a convergent or divergent channel based on its topological configuration (non-uniform cross section). An iron oxide (Fe2O3{\rm{F}}{{\rm{e}}}_{2}{{\rm{O}}}_{3}) nanoparticle is injected into the blood (base fluid). To eliminate the viscous effect in the region of the artery wall, a slip boundary condition is applied. An analysis of the transport phenomena is preferred using the melting heat transfer phenomena, which can work in melting plaques or fats at the vessel walls. The effects of thermal radiation, which is advantageous in cancer therapy, biomedical imaging, hyperthermia, and tumor therapy, are incorporated in heat transport mechanisms. The governing equation for the flow model with realistic boundary conditions is numerically tickled using the RK45 mechanism. The findings reveal that the flow dynamism and thermal behavior are significantly influenced by melting effects. Higher Re\mathrm{Re} can produce spots in which the track of the wall shear stress fluctuates. The melting effects can produce agitation and increase the flow through viscous head losses, causing melting of the blockage. The maximum heat transfer of 5%5 \% is achieved with We{\rm{We}} when the volume friction is kept at 1%1 \% . With higher estimation of inertial forces Re\mathrm{Re}\hspace{1em}and same volume friction, the skin drag coefficient augmented to 34%34 \% . The overall temperature is greater for the divergent flow scenario.

This research paper presents an investigation into the behavior of rarefied flow and heat transfer in a rectangular microchannel utilizing a Cu-water nanofluid. The study employs the thermal lattice Boltzmann method (LBM) with a lattice featuring a double distribution function and a BGK collision model. The simulations are performed using Python software, incorporating slip velocity and temperature jump effects. The primary objective is to analyze the influence of various thermophysical parameters of the coolant fluid on the microchannel, specifically focusing on the characteristics of the Cu-water nanofluid. The study considers laminar flow conditions with nanofluid volume fractions of 2%, 4% and 6%. The findings reveal that both rarefaction effect and Reynolds numbers, as well as the nanoparticle volume fraction, significantly impact the system. Moreover, the investigation evaluates key parameters such as the Nusselt number, skin friction coefficient, temperature jump slip velocity and velocity and temperature profiles. Notably, the nanoparticle volume fraction exhibits minimal influence on the velocity distribution or temperature field, whereas the Nusselt number increases with higher nanoparticle volume fractions. Additionally, the rarefaction effect leads to a reduction in velocity and temperature. At a nanoparticle volume fraction of 2%, increasing the Reynolds number results in elevated velocities and lower temperatures. The skin friction coefficient displays a decreasing trend along the microchannel with increasing Reynolds numbers. Furthermore, an increase in Knudsen numbers corresponds to a decrease in the skin friction coefficient. Finally, an increase in the nanoparticle volume fraction is associated with a decrease in the skin friction coefficient. [ABSTRACT FROM AUTHOR]

This study enlightens the magnetohydrodynamic Jeffery-Hamel flow under an inclined Lorentz force through a non-uniform conduit having slip at walls, which is frequently applied in geothermal applications, electronic cooling devices, and modern energy systems, etc. Therefore, the performance of a two-dimensional purely radial flow inside a converging-diverging channel is explored from the perspective of second law of thermodynamics for Carreau nanofluids. The intersecting walls of conduit are inclined with horizontal plane to construct a converging flow for negative angle (α < 0) and a diverging flow for positive angle (α > 0). Additionally, second law thermodynamic evaluation offers an effective method for improving thermal performance by reducing entropy production. To accomplish the main objective, rigorous physical theories and assumptions are implemented based on the passive control approach of Buongiorno's model. By applying distinctive modifications, the governing equations are renovated into a system of ordinary differential equations, which are solved numerically by a collocated technique based on finite difference code. Simple shear near the wall influences the flow configurations allow compression in a local flow topology in regions of divergent channel. The temperature profiles increase with sophisticated heat source and Brinkman number. Entropy is minimum and uniform with optimum channel angle and velocity slip. [ABSTRACT FROM AUTHOR]

The aim of this work is to present the magnetized flow of Casson nanomaterials confined due to porous space with stability framework. The slip mechanism for thermal concentration diffusion has been elaborated. The shrinking surface with exponential velocity induced the flow. The new block method is imposed for the simulation process. The resulting systems of ODEs of the third and second orders are solved jointly using the block method, which is appropriate for dealing with the different orders of the system of ODEs. From a physical standpoint, graphs of different profiles for increasing values of the various applied parameters have been drawn and discussed in detail. To satisfy the infinite boundary conditions, we assigned numerical values such that all profiles converge asymptotically at η → ∞. Furthermore, numerical results from the block method show that velocity profile declines with rising Casson and porous parameter values, as expected. It is noted that the heat transfer rate enhanced with the thermal slip parameter. A lower thermal profile due to larger Casson fluid parameter is observed. [ABSTRACT FROM AUTHOR]

This article examines the heat and mass transfer capabilities of a constitutive model in a thermally evolving steady laminar Jeffery–Hamel flow through a convergent-plate channel, including streamwise conduction with step changes in uniform wall temperature. A Jeffery–Hamel problem with a simple shear flow is used to undertake a comparative computational analysis of the thermal behavior of a viscoelastic fluid subjected to autocatalytic processes. The flow is tracked in a purely radial orientation with the deployment of coupled stresses in momentum conservation. The computational solutions for the flow, temperature and concentration distribution, and heat and mass transfer coefficient of a viscoelastic fluid obeying the complex Oldroyd-B constitutive equation in laminar converging channel flows are established. The analysis of the impacts of the thermal radiation, the heat source, and the chemical reaction as an autocatalytic process is included in the model, which is valid for fully developed thermal and hydrodynamic flow conditions with a constant heat and mass flux imposed at the wall. In the diverging part of the channel, where vortex compression is the predominant flow topology, there exist patches of local flow compression. On the flow field, the modified relaxation and retardation parameters show an opposing behavior. An Oldroyd-B fluid exhibits higher interactions with nearby vortices in the divergent channel, allowing a complex flow structure. The viscoelastic characteristics are anticipated to change the homogeneous–heterogeneous reaction transport processes, offering tremendous potential for applications in associated sectors. The deceleration flow in the diverging channel and the acceleration flow in the converging channel augment the average Nusselt numbers. [ABSTRACT FROM AUTHOR]

Nowadays, scarcity arises in almost all our basic needs, including water, fuel, and food. Recycling used and scrapped things for a valuable commodity is highly appreciable for compensating for the globally fast-growing demand. This paper aims to investigate waste tyre oil for preparing biodiesel for CI engines by enhancing their performance with hybrid nanoparticles for preparing nanofuel and hybrid nanofuel. The nanoparticles (30–40 nm) of MWCNT and TiO2 were utilized to prepare nanofuels with nanoparticle concentrations of MWCNT (300 ppm) and TiO2 (300 ppm), respectively. In the case of hybrid nanofuel, the nanoparticle concentration of MWCNT (150 ppm) and TiO2 (150 ppm) was preferred. The performance of the proposed nanofuel and hybrid nanofuel with pure diesel was evaluated. The proposed fuel performance outperforms the combustion performance, has higher engine efficiency, and has fewer emissions. The best performances were noticed in hybrid nanofuel that has 32% higher brake thermal efficiency than diesel and 24% and 4% lower BSFC and peak pressure than diesel, respectively. The emission performance is also 29%, 50%, and 13% lower in CO, HC, and CO2 emissions than that in pure diesel. [ABSTRACT FROM AUTHOR]

Modern nanomaterials and their flow dynamism processes promote complex chemical reactions that are necessary for the accurate synthesis of bespoke geometries at high temperatures. Such flow processes are very intricate and involve viscous behavior along with mass and heat transfer. Such flows mechanism can be controlled by external magnetic fields. Mathematical models offer an inexpensive opening into the fundamental properties of these dynamical processes. The homogeneous-heterogeneous reactions for nanofluids flow are established by invoking the Buongiorno's nanofluid model, in which the homogeneous reactions are regulated by first order kinetics occurring in the flowing liquid and the heterogeneous reactions are given by isothermal cubic autocatalytic kinetics. To testify the feasibility of this model, the steady, laminar Jaffrey-Hamel flow problem in the converging conduit is extended to rheological model. The system steady states are evaluated under the scenario where the reactant and the catalyst's diffusion coefficients are equivalent. In order to investigate heat and mass transfer analysis, viscous dissipation affirmation, Joule heating, and homogeneous-heterogeneous reactions are incorporated. The mathematical model prevailing the dimensionless function, velocity for flow, temperature for heat, and nanoparticles volume fraction for concentration are simulated numerically by means of Runge-Kutta method. The numerical algorithm has been validated in comparison to previously published research with extremely good agreement. The acquisition and detailed discussion of distributions of flow structure, heat, concentrations, and average Nusselt, Sherwood number at a wide range of critical characteristics. The fluid velocity in the conduit center increases significantly as the Reynolds number rises. By intensifying the magnetic field, the flow reversal control is accomplished. Applications in the allied domains have enormous promise since the ratio of Brownian and thermophoretic diffusivity has a significant impact on the transport mechanisms of homogeneous-heterogeneous processes. Chemical species A ∗ and B ∗ behave in fundamentally distinct ways in the reduced concentrations. [ABSTRACT FROM AUTHOR]

The mathematical modeling of blood flow with the incorporation of ternary hybrid nanoparticles (i.e., titania, silica, and alumina nanoparticles) is the focus of this work. The flow of blood is simulated using the Casson fluid model. The impacts of ternary hybrid nanoparticles, shape factor, and Geometry of solid nanoparticles are visualized and investigated. The momentum and thermal characteristics of a flowing liquid are determined by considering magnetization, porosity, and nonlinearized radiating thermal flux. The basic partial differential equations resulting from mathematical modeling are turned into non‐linear ordinary differential equations using suitable velocity transforms. The derived nonlinear equations are then numerically calculated using the 4th‐5th order Runge‐Kutta‐Fehlberg method with the shooting technique and analytically solved by the Adomian decomposition method (ADM). The effects of the factors involved on the dimensionless profiles produced are fully addressed. It is found that the Skin friction factor and heat transfer rate in the radial direction upsurge with the augment of both rotation parameter and nanoparticles volume fraction; however, the Skin friction factor drops in the azimuthal direction. Also, results obtained reveal an enhancement in the local Nusselt number with the upsurge in the magnitude of radiation parameter, Rd, solid nanoparticles concentration, φ$\ \varphi $, shape factor value, s, and disk temperature, θf${{\theta }_f}$. For validation, the outcomes of this inquiry were compared to the outcomes of the HAM‐based Mathematica software. In addition, the acquired analytical DRA data are compared to numerical RKF45 values and those given in the literature. [ABSTRACT FROM AUTHOR]