Effects of temperature and solid volume fraction on viscosity of SiO2-MWCNTs/SAE40 hybrid nanofluid as a coolant and lubricant in heat engines

A numerical analysis has been conducted to show the effects of magnetohydrodynamic (MHD) and Joule heating on heat transfer phenomenon in a lid driven triangular cavity. The heat transfer fluid (HTF) has been considered as water based hybrid nanofluid composed of equal quantities of Cu and TiO2 nanoparticles. The bottom wall of the cavity is undulated in sinusoidal pattern and cooled isothermally. The left vertical wall of the cavity is heated while the inclined side is insulated. The two dimensional governing partial differential equations of heat transfer and fluid flow with appropriate boundary conditions have been solved by using Galerkin's finite element method built in COMSOL Multyphysics. The effects of Hartmann number, Joule heating, number of undulation and Richardson number on the flow structure and heat transfer characteristics have been studied in details. The values of Prandtl number and solid volume fraction of hybrid nanoparticles have been considered as fixed. Also, the code validation has been shown. The numerical results have been presented in terms of streamlines, isotherms and average Nusselt number of the hybrid nanofluid for different values of governing parameters. The comparison of heat transfer rate by using hybrid nanofluid, Cu-water nanofluid, TiO2 -water nanofluid and clear water has been also shown. Increasing wave number from 0 to 3 enhances the heat transfer rate by 16.89%. The enhanced rate of mean Nusselt number for hybrid nanofluid is found as 4.11% compared to base fluid.

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Numerical treatment for Casson liquid flow in a microchannel due to porous medium: A hybrid nanoparticles aspects

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/09544062211008933 ◽

2021 ◽

pp. 095440622110089

Author(s):

Gombi Rachappa Manohar ◽

Puttaswamy Venkatesh ◽

Bijjanal Jayanna Gireesha ◽

Gosikere Kenchappa Ramesh

Keyword(s):

Porous Medium ◽

Volume Fraction ◽

Flow Behavior ◽

Solid Volume Fraction ◽

Velocity Slip ◽

Casson Fluid ◽

Hybrid Nanoparticles ◽

Hybrid Nanofluid ◽

Current Investigation ◽

Numerical Treatment

In the current investigation a mathematical model is simplified to explore the numerical treatment for the thermal and flow behavior in a magneto hydrodynamics Casson fluid through a micro channel by taking [Formula: see text] nanoparticles. The combined effects of temperature jump, porous medium and velocity slip are incorporated. Using the dimensionless variables one can obtain the governing differential equations thereafter resolved numerically using RKF45 method. The velocity, temperature, skin friction and Nusselt number coefficient are addressed for different pertaining parameter. The upshots of the current investigation are visualized through graphically elucidation. Out comes shows that larger values of solid volume fraction decreases both velocity and temperature field. Furthermore drag coefficient is increases for increase in magnetic parameter, also hybrid nanofluid gives more impact than nanofluid.

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Effects of Surface Rotation on the Phase Change Process in a 3D Complex-Shaped Cylindrical Cavity with Ventilation Ports and Installed PCM Packed Bed System during Hybrid Nanofluid Convection

Mathematics ◽

10.3390/math9202566 ◽

2021 ◽

Vol 9 (20) ◽

pp. 2566

Author(s):

Lioua Kolsi ◽

Fatih Selimefendigil ◽

Mohamed Omri

Keyword(s):

Phase Transition ◽

Phase Change ◽

Change Process ◽

Volume Fraction ◽

Solid Volume Fraction ◽

Packed Bed ◽

Reynolds Numbers ◽

Hybrid Nanofluid ◽

Surface Rotation ◽

Phase Change Process

The combined effects of surface rotation and using binary nanoparticles on the phase change process in a 3D complex-shaped vented cavity with ventilation ports were studied during nanofluid convection. The geometry was a double T-shaped rotating vented cavity, while hybrid nanofluid contained binary Ag–MgO nano-sized particles. One of the novelties of the study wasthat a vented cavity was first used with the phase change–packed bed (PC–PB) system during nanofluid convection. The PC–PB system contained a spherical-shaped, encapsulated PCM paraffin wax. The Galerkin weighted residual finite element method was used as the solution method. The computations were carried out for varying values of the Reynolds numbers (100 ≤ Re ≤ 500),rotational Reynolds numbers (100 ≤ Rew ≤ 500), size of the ports (0.1L1 ≤ di ≤ 0.5L1), length of the PC–PB system (0.4L1 ≤ L0 ≤ L1), and location of the PC–PB (0 ≤ yp ≤ 0.25H). In the heat transfer fluid, the nanoparticle solid volume fraction amount was taken between 0 and 0.02%. When the fluid stream (Re) and surface rotational speed increased, the phase change process became fast. Effects of surface rotation became effective for lower values of Re while at Re = 100 and Re = 500; full phase transition time (tp) was reduced by about 39.8% and 24.5%. The port size and nanoparticle addition in the base fluid had positive impacts on the phase transition, while 34.8% reduction in tp was obtained at the largest port size, though this amount was only 9.5%, with the highest nanoparticle volume fraction. The length and vertical location of the PC–PB system have impacts on the phase transition dynamics. The reduction and increment amount in the value of tp with varying location and length of the PC–PB zone became 20% and 58%. As convection in cavities with ventilation ports are relevant in many thermal energy systems, the outcomes of this study will be helpful for the initial design and optimization of many PCM-embedded systems encountered in solar power, thermal management, refrigeration, and many other systems.

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Magneto-Hybrid Nanofluids Flow via Mixed Convection past a Radiative Circular Cylinder

Scientific Reports ◽

10.1038/s41598-020-66918-6 ◽

2020 ◽

Vol 10 (1) ◽

Cited By ~ 2

Author(s):

E. R. EL-Zahar ◽

A. M. Rashad ◽

W. Saad ◽

L. F. Seddek

Keyword(s):

Circular Cylinder ◽

Drag Coefficient ◽

Volume Fraction ◽

Solid Volume Fraction ◽

Convective Boundary Condition ◽

Hybrid Nanofluid ◽

Current Analysis ◽

Convective Boundary ◽

Fundamental Parameters ◽

Grid Points

Abstract The goal of the current analysis is to scrutinize the magneto-mixed convective flow of aqueous-based hybrid-nanofluid comprising Alumina and Copper nanoparticles across a horizontal circular cylinder with convective boundary condition. The energy equation is modelled by interpolating the non-linear radiation phenomenon with the assisting and opposing flows. The original equations describing the magneto-hybrid nanofluid motion and energy are converted into non-dimensional equations and solved numerically using a new hybrid linearization-Chebyshev spectral method (HLCSM). HLCSM is a high order spectral semi-analytical numerical method that results in an analytical solution in η-direction and thereby the solution is valid in overall the η-domain, not only at the grid points. The impacts of diverse parameters on the allied apportionment are inspected, and the fallouts are described graphically in the investigation. The physical quantities of interest containing the drag coefficient and the heat transfer rate are predestined versus fundamental parameters, and their outcomes are elucidated. It is witnessed that both drag coefficient and Nusselt number have greater magnitude for Cu-water followed by hybrid nanofluid and Al2O3-water. Moreover, the value of the drag coefficient declines versus the enlarged solid volume fraction. To emphasize the originality of the current analysis, the outcomes are compared with quoted works, and excellent accord is achieved in this consideration.

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Hydrothermal and Entropy Investigation of Ag/MgO/H2O Hybrid Nanofluid Natural Convection in a Novel Shape of Porous Cavity

Applied Sciences ◽

10.3390/app11041722 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1722

Author(s):

Nidal Abu-Libdeh ◽

Fares Redouane ◽

Abderrahmane Aissa ◽

Fateh Mebarek-Oudina ◽

Ahmad Almuhtady ◽

...

Keyword(s):

Magnetic Field ◽

Heat Transfer ◽

Natural Convection ◽

Volume Fraction ◽

Solid Volume Fraction ◽

Hybrid Nanofluid ◽

The Finite Element Method ◽

Governing Equations ◽

Nanofluid Flow ◽

The Magnetic Field

In this study, a new cavity form filled under a constant magnetic field by Ag/MgO/H2O nanofluids and porous media consistent with natural convection and total entropy is examined. The nanofluid flow is considered to be laminar and incompressible, while the advection inertia effect in the porous layer is taken into account by adopting the Darcy–Forchheimer model. The problem is explained in the dimensionless form of the governing equations and solved by the finite element method. The results of the values of Darcy (Da), Hartmann (Ha) and Rayleigh (Ra) numbers, porosity (εp), and the properties of solid volume fraction (ϕ) and flow fields were studied. The findings show that with each improvement in the Ha number, the heat transfer rate becomes more limited, and thus the magnetic field can be used as an outstanding heat transfer controller.

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Influence of a Darcy-Forchheimer porous medium on the flow of a radiative magnetized rotating hybrid nanofluid over a shrinking surface

Scientific Reports ◽

10.1038/s41598-021-03470-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Sumera Dero ◽

Hisamuddin Shaikh ◽

Ghulam Hyder Talpur ◽

Ilyas Khan ◽

Sayer O. Alharbim ◽

...

Keyword(s):

Heat Transfer ◽

Stability Analysis ◽

Differential Equations ◽

Shooting Method ◽

Volume Fraction ◽

Solid Volume Fraction ◽

Dual Solutions ◽

Hybrid Nanofluid ◽

Solution Stability ◽

Shrinking Surface

AbstractIn this paper, the heat transfer properties in the three-dimensional (3D) magnetized with the Darcy-Forchheimer flow over a shrinking surface of the $$Cu + Al_{2} O_{3} /$$ C u + A l 2 O 3 / water hybrid nanofluid with radiation effect were studied. Valid linear similarity variables convert the partial differential equations (PDEs) into the ordinary differential equations (ODEs). With the help of the shootlib function in the Maple software, the generalized model in the form of ODEs is numerically solved by the shooting method. Shooting method can produce non-unique solutions when correct initial assumptions are suggested. The findings are found to have two solutions, thereby contributing to the introduction of a stability analysis that validates the attainability of first solution. Stability analysis is performed by employing if bvp4c method in MATLAB software. The results show limitless values of dual solutions at many calculated parameters allowing the turning points and essential values to not exist. Results reveal that the presence of dual solutions relies on the values of the porosity, coefficient of inertia, magnetic, and suction parameters for the specific values of the other applied parameters. Moreover, it has been noted that dual solutions exist in the ranges of $$F_{s} \le F_{sc}$$ F s ≤ F sc , $$M \ge M_{C}$$ M ≥ M C ,$$S \ge S_{C} ,$$ S ≥ S C , and $$K_{C} \le K$$ K C ≤ K whereas no solution exists in the ranges of $$F_{s} > F_{sc}$$ F s > F sc , $$M < M_{c}$$ M < M c , $$S < S_{c}$$ S < S c , and $$K_{C} > K$$ K C > K . Further, a reduction in the rate of heat transfer is noticed with a rise in the parameter of the copper solid volume fraction.

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Buoyancy Effect on a Micropolar Fluid Flow Past a Vertical Riga Surface Comprising Water-Based SWCNT–MWCNT Hybrid Nanofluid Subject to Partially Slipped and Thermal Stratification: Cattaneo–Christov Model

Mathematical Problems in Engineering ◽

10.1155/2021/6618395 ◽

2021 ◽

Vol 2021 ◽

pp. 1-13

Author(s):

Ahmed Mohammed Alshehri ◽

Hasan Huseyin Coban ◽

Shafiq Ahmad ◽

Umair Khan ◽

Wajdi Mohamad Alghamdi

Keyword(s):

Micropolar Fluid ◽

Thermal Stratification ◽

Volume Fraction ◽

Solid Volume Fraction ◽

Hybrid Nanofluid ◽

Micropolar Fluid Flow ◽

Flux Model ◽

Mixed Convective Flow ◽

Heat Flux Model ◽

Convection Parameter

This paper provides a comprehensive analysis of the mixed convective flow that comprises SWCNT-MWCNT/water hybrid nanofluid containing micropolar fluid through a partially slipped vertical Riga surface. A Cattaneo–Christov heat flux model is used to examine the heat transport rate. The energy equation is gaining more significance with the effect of viscous dissipation and thermal stratification. The flow model is transformed by convenient transformation into nondimensionless form. The numerical results of nonlinear complex equations are collected using the bvp4c built-in function from MATLAB which is based on the finite difference method. The graphical results are obtained for both hybrid nanofluid and simple nanofluid. The temperature distribution for hybrid nanofluid is higher than that for simple nanofluid when the solid volume fraction increases. The axial friction factor increases with solid volume fraction, porosity parameter, and mixed convection parameter. The velocity graph varies inversely with nanofluid volume fraction and micropolar parameter.

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Transpiration and Viscous Dissipation Effects on Entropy Generation in Hybrid Nanofluid Flow over a Nonlinear Radially Stretching Disk

Entropy ◽

10.3390/e20090668 ◽

2018 ◽

Vol 20 (9) ◽

pp. 668 ◽

Cited By ~ 15

Author(s):

Umer Farooq ◽

Muhammad Afridi ◽

Muhammad Qasim ◽

D. Lu

Keyword(s):

Boundary Layer ◽

Viscous Dissipation ◽

Entropy Generation ◽

Numerical Solutions ◽

Volume Fraction ◽

Solid Volume Fraction ◽

Research Work ◽

Dissipation Function ◽

Hybrid Nanofluid ◽

Layer Flow

The present research work explores the effects of suction/injection and viscous dissipation on entropy generation in the boundary layer flow of a hybrid nanofluid (Cu–Al2O3–H2O) over a nonlinear radially stretching porous disk. The energy dissipation function is added in the energy equation in order to incorporate the effects of viscous dissipation. The Tiwari and Das model is used in this work. The flow, heat transfer, and entropy generation analysis have been performed using a modified form of the Maxwell Garnett (MG) and Brinkman nanofluid model for effective thermal conductivity and dynamic viscosity, respectively. Suitable transformations are utilized to obtain a set of self-similar ordinary differential equations. Numerical solutions are obtained using shooting and bvp4c Matlab solver. The comparison of solutions shows excellent agreement. To examine the effects of principal flow parameters like suction/injection, the Eckert number, and solid volume fraction, different graphs are plotted and discussed. It is concluded that entropy generation inside the boundary layer of a hybrid nanofluid is high compared to a convectional nanofluid.

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MHD darcy-forchheimer nanofluid flow and entropy optimization in an odd-shaped enclosure filled with a (MWCNT-Fe3O4/water) using galerkin finite element analysis

Scientific Reports ◽

10.1038/s41598-021-02047-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Wael Al-Kouz ◽

Abderrahmane Aissa ◽

Aimad Koulali ◽

Wasim Jamshed ◽

Hazim Moria ◽

...

Keyword(s):

Finite Element ◽

Rayleigh Number ◽

Volume Fraction ◽

Solid Volume Fraction ◽

Darcy Number ◽

Heated Wall ◽

Entropy Generation Rate ◽

Hybrid Nanofluid ◽

Galerkin Finite Element ◽

The Impact

AbstractMHD nanoliquid convective flow in an odd-shaped cavity filled with a multi-walled carbon nanotube-iron (II, III) oxide (MWCNT-Fe3O4) hybrid nanofluid is reported. The side walls are adiabatic, and the internal and external borders of the cavity are isothermally kept at high and low temperatures of Th and Tc, respectively. The governing equations obtained with the Boussinesq approximation are solved using Galerkin Finite Element Method (GFEM). Impact of Darcy number (Da), Hartmann number (Ha), Rayleigh number (Ra), solid volume fraction (ϕ), and Heated-wall length effect are presented. Outputs are illustrated in forms of streamlines, isotherms, and Nusselt number. The impact of multiple parameters namely Rayleigh number, Darcy number, on entropy generation rate was analyzed and discussed in post-processing under laminar and turbulent flow regimes.

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Physical insights into the heat and mass transfer in Casson hybrid nanofluid flow induced by a Riga plate with thermophoretic particle deposition

Proceedings of the Institution of Mechanical Engineers Part E Journal of Process Mechanical Engineering ◽

10.1177/09544089211039305 ◽

2021 ◽

pp. 095440892110393

Author(s):

JK Madhukesh ◽

A Alhadhrami ◽

R Naveen Kumar ◽

RJ Punith Gowda ◽

BC Prasannakumara ◽

...

Keyword(s):

Particle Deposition ◽

Numerical Solutions ◽

Volume Fraction ◽

Solid Volume Fraction ◽

Boundary Layer Separation ◽

Hybrid Nanofluid ◽

Flow Equations ◽

Pressure Drag ◽

Similarity Transformations ◽

Riga Plate

In applied physics, Riga plate was one of the trademark inventions to overcome the poor conductivity of fluids. This provided an aid to avoid the boundary layer separation, reduce the friction as well as the pressure drag of submarines. This particular study has a lot of importance in numerous manufacturing, industrial and engineering fields. The current study deals with the laminar, steady flow of a Casson hybrid nanoliquid induced by a Riga plate in the presence of a porous medium. Appropriate similarity transformations are used to reduce the fluid flow equations into a system of ordinary differential equations. Later, for these reduced equations, an effective numerical method called the fourth fifth-order Runge–Kutta–Fehlberg process with shooting technique is used to obtain the numerical solutions. The influences of involved parameters on the flow fields are demonstrated graphically. Results reveal that the velocity of the Casson hybrid nanofluid declines with an increase in the solid volume fraction and porosity parameter. The velocity gradient increases for an increase in values of the modified Hartmann number. Thermal distribution enhances with an increase in the values of Biot number as well as heat source/sink parameter.

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