Heat Transfer Improvement in MHD Natural Convection Flow of Graphite Oxide/Carbon Nanotubes-Methanol Based Casson Nanofluids Past a Horizontal Circular Cylinder

This numerical investigation intends to present the impact of nanoparticles volume fraction, Casson, and magnetic force on natural convection in the boundary layer region of a horizontal cylinder in a Casson nanofluid under constant heat flux boundary conditions. Methanol is considered as a host Casson fluid. Graphite oxide (GO), single and multiple walls carbon nanotubes (SWCNTs and MWCNTs) nanoparticles have been incorporated to support the heat transfer performances of the host fluid. The Keller box technique is employed to solve the transformed governing equations. Our numerical findings were in an excellent agreement with the preceding literature. Graphical results of the effect of the relevant parameters on some physical quantities related to examine the behavior of Casson nanofluid flow were obtained, and they confirmed that an augmentation in Casson parameter results in a decline in local skin friction, velocity, or temperature, as well as leading to an increment in local Nusselt number. Furthermore, MWCNTs are the most efficient in improving the rate of heat transfer and velocity, and they possess the lowest temperature.

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Natural convection from cross blade inside a nanofluid-filled cavity using ISPH method

International Journal of Numerical Methods for Heat &amp Fluid Flow ◽

10.1108/hff-12-2019-0863 ◽

2020 ◽

Vol 30 (10) ◽

pp. 4629-4648

Author(s):

Zehba A.S. Raizah

Keyword(s):

Heat Transfer ◽

Natural Convection ◽

Rayleigh Number ◽

Circular Cylinder ◽

Volume Fraction ◽

Working Fluid ◽

Convection Flow ◽

Physical Parameters ◽

Cool Temperature ◽

Content Type

Purpose The purpose of this study is to apply the incompressible smoothed particle hydrodynamics method for simulating the natural convection flow inside a cavity including cross blades or circular cylinder cylinder. Design/methodology/approach The base fluid is water and copper-water nanofluid is treated as a working fluid. The left and rights walls are maintained at a cool temperature, the horizontal cavity walls are isolated and the inner shape was heated. The physical parameters are the length of the blades L_Blade, the number of cross blades, circular cylinder radius L_R, Rayleigh number Ra and the nanoparticles volume fraction. Findings The results reveal that the lengths of the cross blade, number of the blades and radius of the circular cylinder is working as an enhancement factor for heat transfer and fluid flows inside a cavity. Adding nanoparticles augments heat transfer and reduces the fluid flow intensity inside a cavity. The best case for buoyancy-driven flow was obtained when the inner shape is the circular cylinder at a higher Rayleigh number. Originality/value This work uses a distinctive numerical method to study the natural convection heat from cross blades inside a cavity filled with nanofluid. It provides a new analysis of this issue and presented good results.

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ISPH simulations of natural convection from heated rotating paddles on a circular cylinder inside a cross-shaped cavity filled with a nanofluid

10.22541/au.160640288.84638521/v1 ◽

2020 ◽

Author(s):

Abdelraheem Mahmoud Aly ◽

Ehab Mahmoud

Keyword(s):

Heat Transfer ◽

Porous Media ◽

Nusselt Number ◽

Fluid Flow ◽

Natural Convection ◽

Circular Cylinder ◽

Average Nusselt Number ◽

Volume Fraction ◽

Heterogeneous Porous Media ◽

Convection Flow

The numerical simulations of the uniform circular rotation of paddles on circular cylinder results natural convection flow of Al2O3-water in a cross-shaped porous cavity were performed by incompressible representation of smoothed particle hydrodynamics entitled ISPH method. The two vertical area of a cross-shaped cavity is saturated with homogeneous porous media and the whole horizontal area of a cross-shaped cavity is saturated with heterogeneous porous media. The inner paddles on the circular cylinder are rotating around their center by a uniform circular velocity. The whole embedded body of paddles on a circular cylinder has temperature Th. The wall-sides of a cross-shaped cavity are positioned at a temperature Tc. The current geometry can be applied in analysis and understanding the thermophysical behaviors of the electronic motors. The angular velocity is taken as ! = 7:15 and consequently the natural convection case is only considered due to the low speed of inner rotating shape. The performed simulations are represented in the graphical for the temperature distributions, velocity fields and tabular forms for average Nusselt number. The results revealed that an augmentation on paddle length rises the heat transfer and speed of fluid flow inside a cross shaped cavity. Also, an incrementation on Rayleigh number augments the heat transfer and speed of the fluid flow inside a cross-shaped cavity. The fluid flow is circulated only around the rotating inner shape when Darcy parameter decreases to Da = 105. Average Nusselt number Nu enhances by an increment on the paddle lengths and nanoparticles volume fraction

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Performance of heat transfer in MHD mixed convection flow using nanofluids in the presence of viscous dissipation: Local non-similarity solution

Modern Physics Letters B ◽

10.1142/s0217984920501018 ◽

2020 ◽

Vol 34 (11) ◽

pp. 2050101

Author(s):

Aamir Hamid ◽

Masood Khan ◽

Alamdar Hussain

Keyword(s):

Heat Transfer ◽

Viscous Dissipation ◽

Heat Generation ◽

Volume Fraction ◽

Convection Flow ◽

Convective Boundary ◽

Nonlinear Odes ◽

Suction Parameter ◽

Water Base ◽

The Impact

In this study, an investigation has been carried out to examine the effects of thermal radiation, heat generation/absorption, viscous dissipation and suction parameter on MHD flow of water-base nanofluid (Ag, Cu, Al2O3, CuO and TiO2). This study also focused on the mixed convective flow of water-base nanofluid due to a vertical permeable plate in the presence of convective boundary condition. Further, heat transfer has been inspected for water-base fluid influenced by heat generation/absorption and viscous dissipation. Moreover, the governing equations are reduced to nonlinear ordinary differential equations via Sparrow–Quack–Boerner local non-similarity method. These nonlinear ODEs are simulated numerically by means of Runge–Kutta–Fehlberg method (RKF-45). The impact of pertinent parameters on the dimensionless velocity, nanofluid temperature, skin friction and local Nusselt number are discussed and displayed. The results match with a special case of formerly available work. The present exploration exhibits that nanoparticle volume fraction increases the velocity and temperature of Cu-water nanofluid. It is also shown that magnetic parameter reduces the heat transfer rate.

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Study of Carbon Nanotubes with a Casson Fluid in a Vertical Channel of Porous Media under MHD and Dufour Effect

Journal of Scientific Research ◽

10.3329/jsr.v13i1.47458 ◽

2021 ◽

Vol 13 (1) ◽

pp. 31-45

Author(s):

S. Hazarika ◽

S. Ahmed

Keyword(s):

Carbon Nanotubes ◽

Volume Fraction ◽

Saturated Porous Medium ◽

Fluid Velocity ◽

Vertical Channel ◽

Casson Fluid ◽

Engine Oil ◽

Single Wall Carbon Nanotubes ◽

Physical Parameters ◽

The Impact

An analysis is conducted to investigate the problem of heat/mass transfer in MHD free convective flow of Casson-fluid in a vertical channel embedded with saturated porous medium past through carbon nanotubes in the form of single-wall carbon nanotubes (SWCNTs) and multiple-wall carbon nanotubes (MWCNTs) with engine oil as base fluid. In this article, the impact of CNT’s on velocity, temperature, shear stress and rate of heat transfer of the nanofluid has been investigated and studied graphically for the effects of different key physical parameters involved. The validity of this flow model is presented and is found satisfactory agreement with published results. The results state that, fluid velocity accelerates for greater values of Casson parameter and nanoparticles volume fraction, while thermal radiation (R) and heat generation (Q) assume a significant role in CNT's. Applications of this study arise in broad area of science and engineering such as thermal conductivity, energy storage, biomedical applications, air and water filtration, fibers and fabrics.

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Thermal Charging Optimization of a Wavy-Shaped Nano-Enhanced Thermal Storage Unit

Molecules ◽

10.3390/molecules26051496 ◽

2021 ◽

Vol 26 (5) ◽

pp. 1496

Author(s):

Mohammad Ghalambaz ◽

S.A.M. Mehryan ◽

Ahmad Hajjar ◽

Mohammad Yacoub Al Shdaifat ◽

Obai Younis ◽

...

Keyword(s):

Heat Transfer ◽

Natural Convection ◽

Phase Change ◽

Volume Fraction ◽

Thermal Storage ◽

Wave Number ◽

Storage Unit ◽

Charging Time ◽

Phase Change Heat Transfer ◽

The Impact

A wavy shape was used to enhance the thermal heat transfer in a shell-tube latent heat thermal energy storage (LHTES) unit. The thermal storage unit was filled with CuO–coconut oil nano-enhanced phase change material (NePCM). The enthalpy-porosity approach was employed to model the phase change heat transfer in the presence of natural convection effects in the molten NePCM. The finite element method was applied to integrate the governing equations for fluid motion and phase change heat transfer. The impact of wave amplitude and wave number of the heated tube, as well as the volume concertation of nanoparticles on the full-charging time of the LHTES unit, was addressed. The Taguchi optimization method was used to find an optimum design of the LHTES unit. The results showed that an increase in the volume fraction of nanoparticles reduces the charging time. Moreover, the waviness of the tube resists the natural convection flow circulation in the phase change domain and could increase the charging time.

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Numerical Investigation of Heat Transfer with Natural Convection in a Regularly Heated Elliptical Cylinder Submerged in a Square Fence Loaded With a Nanofluid

International Journal of Mathematical Models and Methods in Applied Sciences ◽

10.46300/9101.2021.15.29 ◽

2021 ◽

Vol 15 ◽

pp. 223-232

Author(s):

Djedid Taloub ◽

Adelkarim Bouras ◽

Zied Driss

Keyword(s):

Heat Transfer ◽

Natural Convection ◽

Volume Fraction ◽

Fixed Temperature ◽

Nusselt Numbers ◽

Numerical Research ◽

Finite Volume Approach ◽

The Impact ◽

Rayleigh Numbers ◽

Transfer Flow

During this first paper, numerical research from the natural convection of steady-state laminar heat transfer into a horizontal ring within a heated internal elliptical surface and a cold external square surface is presented. A Cu - water nanofluid, traverses this annular space. For different thermal Rayleigh numbers varying from 103 to 2.5x105 and different volume fractions from the nanoparticles. The arrangement from equations directing the problem was resolved numerically with the Fluent computational language founded on the finite volume approach. Based approaching the Boussinesq approach. The interior and exterior surfaces from the two cylinders are maintained at a fixed temperature. We investigated the impacts of various thermal Rayleigh numbers, the volume fraction from the nanoparticles, and the effect of the eccentricity of the internal cylinder on the natural convection. The results are shown within the figure of isocurrents, isotherms, and mean and local Nusselt numbers. The objective of this investigation is to examine the impact of different parameters on the heat transfer flow.

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Melting Heat Transfer and MHD Boundary Layer Flow of Eyring-Powell Nanofluid Over a Nonlinear Stretching Sheet with Slip

International Journal of Applied Mechanics and Engineering ◽

10.2478/ijame-2019-0011 ◽

2019 ◽

Vol 24 (1) ◽

pp. 161-178 ◽

Cited By ~ 1

Author(s):

N. Vijaya Bhaskar Reddy ◽

N. Kishan ◽

C. Srinivas Reddy

Keyword(s):

Heat Transfer ◽

Boundary Layer ◽

Boundary Layer Flow ◽

Volume Fraction ◽

Skin Friction Coefficient ◽

Physical Parameters ◽

Local Skin ◽

Layer Flow ◽

Nonlinear Stretching ◽

The Impact

Abstract The steady laminar incompressible viscous magneto hydrodynamic boundary layer flow of an Eyring- Powell fluid over a nonlinear stretching flat surface in a nanofluid with slip condition and heat transfer through melting effect has been investigated numerically. The resulting nonlinear governing partial differential equations with associated boundary conditions of the problem have been formulated and transformed into a non-similar form. The resultant equations are then solved numerically using the Runge-Kutta fourth order method along with the shooting technique. The physical significance of different parameters on the velocity, temperature and nanoparticle volume fraction profiles is discussed through graphical illustrations. The impact of physical parameters on the local skin friction coefficient and rate of heat transfer is shown in tabulated form.

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Study of Triangular Fuzzy Hybrid Nanofluids on the Natural Convection Flow and Heat Transfer between Two Vertical Plates

Computational Intelligence and Neuroscience ◽

10.1155/2021/3678335 ◽

2021 ◽

Vol 2021 ◽

pp. 1-15

Author(s):

Muhammad Nadeem ◽

Ahmed Elmoasry ◽

Imran Siddique ◽

Fahd Jarad ◽

Rana Muhammad Zulqarnain ◽

...

Keyword(s):

Heat Transfer ◽

Natural Convection ◽

Volume Fraction ◽

Computational Cost ◽

Numerical Approach ◽

Hybrid Nanoparticles ◽

Convection Flow ◽

Hybrid Nanofluid ◽

Parallel Plates ◽

Highly Nonlinear

The prime objective of the current study is to examine the effects of third-grade hybrid nanofluid with natural convection utilizing the ferro-particle Fe 3 O 4 and titanium dioxide TiO 2 and sodium alginate (SA) as a host fluid, flowing through vertical parallel plates, under the fuzzy atmosphere. The dimensionless highly nonlinear coupled ordinary differential equations are computed adopting the bvp4c numerical approach. This is an extremely effective technique with a low computational cost. For validation, it is found that as the volume fraction of Fe 3 O 4 + TiO 2 hybrid nanoparticles rises, so does the heat transfer rate. The current and existing results with their comparisons are shown in the form of the tables. The present findings are in good agreement with their previous numerical and analytical results in a crisp atmosphere. The nanoparticles volume fraction of Fe 3 O 4 and TiO 2 is taken as uncertain parameters in terms of triangular fuzzy numbers (TFNs) [0, 0.05, 0.1]. The TFNs are controlled by α − cut and the variability of the uncertainty is studied through triangular membership function (MF).

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Heat transfer in natural convection flow of nanofluid along a vertical wavy plate with variable heat flux

Thermal Science ◽

10.2298/tsci161012014m ◽

2019 ◽

Vol 23 (1) ◽

pp. 179-190 ◽

Cited By ~ 2

Author(s):

Irfan Mustafa ◽

Tariq Javed

Keyword(s):

Heat Transfer ◽

Heat Flux ◽

Natural Convection ◽

Pure Water ◽

Wavy Surface ◽

Convection Flow ◽

Natural Convection Flow ◽

Local Skin ◽

Variable Heat ◽

Variable Heat Flux

The present analysis is concerned to examine the enhancement of heat transfer in natural convection flow of nanofluid through a vertical wavy plate assumed at variable heat flux. The rate of heat transfer in nanofluid flow as compared to pure water can be increased due to increase the density of nanofluid which depends on the density and concentration of nanoparticles. For this analysis, Tiwari and Das model is used by considering two nanoparticles i. e. Al2O3 and Cu are suspended in a base fluid (water). A very efficient implicit finite difference technique converges quadratically is applied on the concerning PDE for numerical solution. The effects of pertinent parameters namely, volume fraction parameter of nanoparticle, wavy surface amplitude, Prandtl number and exponent of variable heat flux on streamlines, isothermal lines, local skin friction coefficient and local Nusselt number are shown through graphs. In this analysis, a maximum heat transfer rate is noted in Cu-water nanofluid through a vertical wavy surface as compared to Al2O3-water and pure water.

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Influence of Single- and Multi-Wall Carbon Nanotubes on Magnetohydrodynamic Stagnation Point Nanofluid Flow over Variable Thicker Surface with Concave and Convex Effects

Mathematics ◽

10.3390/math8010104 ◽

2020 ◽

Vol 8 (1) ◽

pp. 104 ◽

Cited By ~ 15

Author(s):

Anum Shafiq ◽

Ilyas Khan ◽

Ghulam Rasool ◽

El-Sayed M. Sherif ◽

Asiful H. Sheikh

Keyword(s):

Magnetic Field ◽

Heat Transfer ◽

Carbon Nanotubes ◽

Velocity Field ◽

Base Fluid ◽

Volume Fraction ◽

Brownian Diffusion ◽

System Of Nonlinear Equations ◽

Multi Wall Carbon Nanotubes ◽

The Impact

This paper reports a theoretical study on the magnetohydrodynamic flow and heat exchange of carbon nanotubes (CNTs)-based nanoliquid over a variable thicker surface. Two types of carbon nanotubes (CNTs) are accounted for saturation in base fluid. Particularly, the single-walled and multi-walled carbon nanotubes, best known as SWCNTs and MWCNTs, are used. Kerosene oil is taken as the base fluid for the suspension of nanoparticles. The model involves the impact of the thermal radiation and induced magnetic field. However, a tiny Reynolds number is assumed to ignore the magnetic induction. The system of nonlinear equations is obtained by reasonably adjusted transformations. The analytic solution is obtained by utilizing a notable procedure called optimal homotopy analysis technique (O-HAM). The impact of prominent parameters, such as the magnetic field parameter, Brownian diffusion, Thermophoresis, and others, on the dimensionless velocity field and thermal distribution is reported graphically. A comprehensive discussion is given after each graph that summarizes the influence of the respective parameters on the flow profiles. The behavior of the friction coefficient and the rate of heat transfer (Nusselt number) at the surface (y = 0) are given at the end of the text in tabular form. Some existing solutions of the specific cases have been checked as the special case of the solution acquired here. The results indicate that MWCNTs cause enhancement in the velocity field compared with SWCNTs when there is an increment in nanoparticle volume fraction. Furthermore, the temperature profile rises with an increment in radiation estimator for both SWCNT and MWCNT and, finally, the heat transfer rate lessens for increments in the magnetic parameter for both types of nanotubes.

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