The present article focuses on the effect of exponential space-dependent heat source on magneto-hydrodynamic Casson fluid flow over a curved stretching sheet along with chemical reaction and ...convective heat and mass flux boundary conditions. The equations that govern the flow are reduced from system of partial differential equations to system of ordinary differential equations with the assistance of similarity transformations, and after that, they are solved using the numerical technique Runge–Kutta–Fehlberg fourth–fifth-order method. The obtained numerical values are plotted through graphs for velocity, temperature and concentration profiles with various parameters, and the variations based on these plots are discussed. Here, it is incurred that the velocity and concentration fields increase with increasing curvature parameter, whereas temperature profile shows inverse relation. Also, increment of Casson parameter shows the significant change in all flow profiles. Both thermal Biot number and concentration Biot number have increasing impact on temperature and concentration profiles, respectively.
The unsteady thermal behavior of a porous longitudinal fin in a fully wet circumstance in the existence of convection as well as radiation effect is modeled in the present analysis. The thickness of ...the fin is assumed to vary with the length of the fin. Therefore, different profiles of the fin such as rectangular, convex, as well as triangular-shaped fin have been considered. Darcy’s model is imposed to study porous nature. The derived nonlinear partial differential equation is non-dimensionalized and solved numerically with the help of Maple software by the Finite Difference Method. The transient thermal response and fin efficiency for diverse values of the significant parameters have been discussed graphically. A comparative analysis of three different shaped fins has been performed. It is found that the temperature drop rate is faster in triangular fin and efficiency is higher in rectangular fin.
During the production of iron(iii) oxide and silver nanoparticles where water is inevitable, little is known on the transport phenomenon in a rectangular cavity mounted with two heated fins on the ...bottom wall where buoyancy and Lorentz forces are significant. The natural convection heat transfer of hybrid nanofluid flow in a rectangular cavity mounted with two heated fins on the bottom wall is studied. The hybrid nanofluid containing the nanoparticles of
Fe
3
O
4
and
Ag
with water as base fluid is considered for the analysis. The derived governing partial differential equations are non-dimensionalized and solved numerically by applying the finite element method. It was concluded that at lower Rayleigh number and higher Hartmann number laminar flow is visible and at higher
Ra
and lower
Ha
, turbulent flow is seen. The intensity of the velocity profile and streamline function rises with the Rayleigh number. The nanoparticle volume fraction also affects the thermal profile and streamlined function.
Bioconvection in magneto-nanoliquid embedded with gyrotactic microorganisms across an elongated sheet with velocity slip of second order is addressed. Nonlinear thermal radiation and chemical ...reaction aspects are retained in energy and concentration equations. Numerical simulations for the modeled problem are proposed via Runge–Kutta–Fehlberg-based shooting technique. Special attention is given to the impact of involved parameters on the profiles of motile microorganisms, nanoparticle volume fraction, temperature and velocity. Our simulations figured out that assisting flow generates more heat transfer than the opposing flow situation. The motile microorganism’s boundary layer decayed for higher bioconvection Peclet and bioconvection Lewis numbers.
Purpose
This paper aims to study the temperature performance with natural convection and radiation effect on a porous fin in fully wet condition.
Design/methodology/approach
The finite element method ...(FEM) is applied to generate numerical solution of the obtained non-dimensional ordinary differential equation containing highly nonlinear terms. The parameters which impact on the heat transfer of fin have been scrutinized by means of plotted graphs.
Findings
The porous fin is taken for the analysis in radial profile moving with constant velocity. Here, the thermal conductivity is considered to be temperature dependent. The Darcy’s model has been implemented to study the heat transfer analysis.
Originality/value
The paper is genuine in its type, and there are hardly any works on fins as per the authors’ knowledge.
•Hybrid nanofluid flow over the porous longitudinal moving fin is addressed.•Darcy's model is implemented for the flow behavior.•Thermal radiation and natural convection effects are ...considered.•Differential system is non-dimensionalized and numerically solved via RKF.
The numerical investigation of nanoparticles embedded water based hybrid nanoliquid flow over porous longitudinal fin moving with constant velocity is carried out together with thermal radiation and natural convection condition. Darcy's model is implemented for the flow behaviour. The two types of boundary conditions are considered at the tip i.e., insulated tip fin and fin with known convective condition.
The modelled ordinary differential equation is non-dimensionalized and tackled mathematically by applying RKF (Runge Kutta Fehlberg) technique.
The parametric evaluation is carried out through graphs and interpreted physically. From obtained outcomes, it is noticed that, fin with known convective coefficient at the tip shows greater heat transfer rate than fin with insulated tip.
Purpose
Outstanding features such as superior electrical conductivity and thermal conductivity of alloy nanoparticles with working fluids make them ideal materials to be used as coolants in ...microelectromechanical systems (MEMSs). This paper aims to investigate the effects of different alloy nanoparticles such as AA7075 and Ti6Al4V on microchannel flow of magneto-nanoliquids with partial slip and convective boundary conditions. Flow features are explored with the effects of magnetism and nanoparticle shape. Heat transport of fluid includes radiative heat, internal heat source/sink, viscous and Joule heating phenomena.
Design/methodology/approach
Suitable dimensionless variables are used to reduce dimensional governing equations into dimensionless ordinary differential equations. The relevant dimensionless ordinary differential systems are computed numerically by using Runge–Kutta–Fehlberg-based shooting approach. Pertinent results of velocity, temperature, entropy number and Bejan number for assorted values of physical parameters are comprehensively discussed. Also, a closed-form solution is obtained for momentum equation for a particular case. Analytical results agree perfectly with numerical results.
Findings
It is established that the entropy production can be improved with radiative heat, Joule heating, convective heating and viscous dissipation aspects. The entropy production is higher in the case of Ti6Al4V-H2O nanofluid than AA7075-H2O. Further, the inequality Ns(ξ)Sphere > Ns(ξ)Hexahedran > Ns(ξ)Tetrahydran > Ns(ξ)Column > Ns(ξ)Lamina holds true.
Originality/value
Effects of aluminium and titanium alloy nanoparticles in microchannel flows by using viscous dissipation and Joule heating are investigated for the first time. Flow features are explored with the effects of magnetism and nanoparticle shape. The results for different alloy nanoparticles such as AA7075 and Ti6Al4V have been compared.
The aim of the current work is to explore how heat transfer can be enhanced by variations in the basic properties of fluids in the presence of free convection with the aid of suspended hybrid ...nanofluids. Also, the influence of the Laurentz force on the flow is considered. The mathematical equations are converted into a pair of self-similarity equations by applying appropriate transformations. The reduced similarity equivalences are then solved numerically by Runge-Kutta-Fehlberg 45th-order method. To gain better perception of the problem, the flow and energy transfer characteristics are explored for distinct values of significant factors such as variable viscosity, convection, magnetic field, and volume fraction. The results acquired are in good agreement with previously published results. The noteworthy finding is that the thermal conductivity is greater in hybrid nanofluid than that of a regular nanofluid in the presence of specified factors. The boundary layer thickness of both hybrid nanofluid and normal nanofluid diminishes due to decrease in variable viscosity. The fluid flow and temperature of the hybrid nanofluid and normal nanofluid increases as there is a rise in volume fraction.
The heat flow in microchannels can be established in numerous applications such as micro air vehicles, mechanical–electromechanical systems, cooling of electronic devices and micro heat exchanger ...systems. Heat flow optimization deliberates the function of entropy generation minimization (EGM) in engineering applications. Hence, this paper investigates the heat transport of non-Newtonian magneto-Carreau fluid in a microchannel with EGM. Mathematical modeling incorporates the Carreau fluid model. Further, viscous heating, Joule heating and convective heating aspects are also analyzed. The physical features of entropy production in the flow of non-Newtonian Carreau fluid in a microchannel are the major focus of this model. Dimensionless variables are executed for the simplicity of basic equations. The subsequent system is treated by using finite element method. Behaviors of effective parameters on velocity, Bejan number, entropy generation rate and temperature are interpreted. It is established that EGM is occurred for larger values of Weissenberg number. The Carreau fluid exponent is positively related to Bejan number, whereas it is negatively related to EG, temperature and velocity fields.
The porous fin of radial profile is considered in the current analysis along with the radiation and thermal-dependent internal heat generation condition. In addition, two different cases have been ...examined based on the linear dependency and exponential dependency of thermal conductivity on temperature. The Darcy’s law is used to study the porous nature of fin. The modeled governing equation is a second-order nonlinear ordinary differential equation and is solved via Runge–Kutta–Fehlberg fourth–fifth-order method. The important terms are grouped as dimensionless parameters and discussed their influence on the heat transfer rate and thermal stresses of the fin. The thermal stresses like radial stress and tangential stress are addressed comprehensively and interpreted graphically. Also, the fin efficiency is defined and discussed graphically. It is found that the tangential stress shows higher compression near fin base region and larger tensile stress near tip radius.
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