scholarly journals 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

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.

Mathematical Analysis of Thermal Energy Distribution in a Hybridized Mixed Convective Flow

2021 ◽  
Vol 10 (2) ◽  
pp. 222-231
Author(s):  
Shafiq Ahmad ◽  
Sohail Nadeem ◽  
Aysha Rehman
Keyword(s):  
Convective Flow ◽  
Volume Fraction ◽  
Variable Viscosity ◽  
Solid Volume Fraction ◽  
Momentum Equation ◽  
Hybrid Nanofluid ◽  
Governing Equations ◽  
Porosity Parameter ◽  
Heat Transfer Phenomenon ◽  
Mixed Convective Flow

The mixed convective flow of hybrid nanofluid (SWCNT-MWCNT/EG) containing micropolar fluid past a Riga surface embedded in porous medium is explored in detail throughout this study. In the momentum equation, the Darcy Forchheimer effect is used. The heat transfer phenomenon is exploited with viscous dissipation and thermal stratification over a non-Fourier heat flux model. PDEs are transformed into the necessary governing equations using transformations. The numerical results of non-linear governing equations are collected using Matlab function bvp4c. Graphical representations of the effects of relevant parameters on velocity, skin friction, and temperature are shown. The comparison of simple nanofluid and hybrid nanofluid is discussed in graphs. The temperature field is higher for hybrid nanofluid than simple nanofluid when solid volume fraction enhances. With increasing solid volume fraction, porosity parameter, and mixed convection parameter, the axial friction factor rises. The momentum boundary layer is inversely proportional to the slip parameter, Hartman number, variable viscosity and the porosity parameter.

Dual similarity solutions because of mixed convective flow of a double-nanoparticles hybrid nanofluid: critical points and stability analysis

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ioan Pop ◽  
Mohammadreza Nademi Rostami ◽  
Saeed Dinarvand
Keyword(s):  
Stability Analysis ◽  
Differential Equations ◽  
Flow Regime ◽  
Magnetic Parameter ◽  
Volume Fraction ◽  
Similarity Solutions ◽  
Hybrid Nanofluid ◽  
Content Type ◽  
Buoyancy Parameter ◽  
Mixed Convective Flow

Purpose The purpose of this article is to study the steady laminar magnetohydrodynamics mixed convection stagnation-point flow of an alumina-graphene/water hybrid nanofluid with spherical nanoparticles over a vertical permeable plate with focus on dual similarity solutions. Design/methodology/approach The single-phase hybrid nanofluid modeling is based on nanoparticles and base fluid masses instead of volume fraction of first and second nanoparticles as inputs. After substituting pertinent similarity variables into the basic partial differential equations governing on the problem, the authors obtain a complicated system of nondimensional ordinary differential equations, which has non-unique solution in a certain range of the buoyancy parameter. It is worth mentioning that, the stability analysis of the solutions is also presented and it is shown that always the first solutions are stable and physically realizable. Findings It is proved that the magnetic parameter and the wall permeability parameter widen the range of the buoyancy parameter for which the solution exists; however, the opposite trend is valid for second nanoparticle mass. Besides, mass suction at the surface of the plate as well as magnetic parameter leads to reduce both hydrodynamic and thermal boundary layer thicknesses. Moreover, the assisting flow regime always has higher values of similarity skin friction and Nusselt number relative to opposing flow regime. Originality/value A novel mass-based model of the hybridity in nanofluids has been used to study the foregoing problem with focus on dual similarity solutions. The results of this paper are completely original and, to the best of the authors’ knowledge, the numerical results of the present paper were never published by any researcher.

scholarly journals Entropy Generation in MHD Second-Grade Nanofluid Thin Film Flow Containing CNTs with Cattaneo-Christov Heat Flux Model Past an Unsteady Stretching Sheet

2020 ◽  
Vol 10 (8) ◽  
pp. 2720 ◽  
Author(s):  
Zahir Shah ◽  
Ebraheem O. Alzahrani ◽  
Abdullah Dawar ◽  
Wajdi Alghamdi ◽  
Malik Zaka Ullah
Keyword(s):  
Entropy Generation ◽  
Volume Fraction ◽  
Second Grade ◽  
Thin Film Flow ◽  
Second Grade Fluid ◽  
Fluid Parameter ◽  
Grade Fluid ◽  
Flux Model ◽  
Walled Carbon Nanotubes ◽  
Heat Flux Model

Entropy generation plays a significant role in several complex processes, extending from cosmology to biology. The entropy generation minimization procedure can be applied for the optimization of mechanical systems including heat exchangers, elements of nuclear and thermal power plants, ventilation and air-conditioning systems. In order to present our analysis, entropy generation in a thin film flow of second grade nanofluid holding single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs) with a Cattaneo–Christov heat flux model is studied in this article. The flow is considered passing a linearly extending surface. A variable magnetic field with aligned angle ε is functioned along the extending sheet. With the aid of the homotopy analysis method (HAM), the fluid flow model is elucidated. The impressions of embedded factors on the flow are obtainable through figures and discussed in detail. It is observed that the velocity profile escalated with the increasing values of volume fraction of nanoparticles and second grade fluid parameter. The higher values of volume fraction of nanoparticles, second grade fluid parameter, non-linear heat source/sink, and thermal radiation parameter intensified the temperature profile. Surface drag force escalated with heightening values of nanoparticles volume fraction, unsteadiness, film thickness, magnetic, and second grade fluid parameters. Entropy generation increased with enhancing values of magnetic parameter, Brinkman number, and Reynolds number.

scholarly journals Mixed convective hybrid nanofluid flow in lid-driven undulated cavity: effect of MHD and Joule heating

2019 ◽  
Vol 16 (2) ◽  
pp. 109-126 ◽  
Author(s):  
Ishrat Zahan ◽  
R Nasrin ◽  
M A Alim
Keyword(s):  
Heat Transfer ◽  
Nusselt Number ◽  
Heat Transfer Rate ◽  
Joule Heating ◽  
Transfer Rate ◽  
Volume Fraction ◽  
Solid Volume Fraction ◽  
Hybrid Nanoparticles ◽  
Wave Number ◽  
Hybrid Nanofluid

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.

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

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.

scholarly journals 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 ◽  
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.

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

2020 ◽  
Vol 10 (1) ◽  
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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