Numerical Simulation of Nanofluid-Cooling Enhancement of Three Fins Mounted in a Horizontal Channel

2016 ◽  
Vol 138 (9) ◽  
Author(s):  
Moussa Khentoul ◽  
Rachid Bessaïh
Keyword(s):  
Volume Fraction ◽  
Numerical Study ◽  
Solid Volume Fraction ◽  
Horizontal Channel ◽  
Thermal Fields ◽  
Nusselt Numbers ◽  
Simpler Algorithm ◽  
Laminar Mixed Convection ◽  
Cooling Enhancement ◽  
Volume Method

This article presents a numerical study of two-dimensional laminar mixed convection in a horizontal channel. The upper horizontal wall of the channel is insulated. The governing equations were solved by using the finite volume method based on the simpler algorithm. Comparisons with previous results were performed and found to be in excellent agreement. The results were presented in terms of streamlines, isotherms, local and average Nusselt numbers for the Richardson number (0 ≤ Ri ≤ 10), Reynolds number (5 ≤ Re ≤ 100), solid volume fraction of nanoparticles (0 ≤ ϕ ≤ 0.10), and the type of nanofluids (Cu, Ag, Al2O3, and TiO2). The results show that the previous parameters have considerable effects on the flow and thermal fields. It was found that the heat transfer increases with increasing of Ra, Re, and ϕ.

scholarly journals Numerical Simulation of the Cooling of Heated Electronic Blocks in Horizontal Channel by Mixed Convection of Nanofluids

2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Mustapha Ait Hssain ◽  
Rachid Mir ◽  
Youness El Hammami
Keyword(s):  
Heat Transfer ◽  
Mixed Convection ◽  
Volume Fraction ◽  
Numerical Study ◽  
Solid Volume Fraction ◽  
Simple Algorithm ◽  
Separation Distance ◽  
Horizontal Channel ◽  
Laminar Mixed Convection ◽  
Finite Volume Approach

The present work is devoted to the numerical study of steady and laminar mixed convection of nanofluid (water nanoparticles) in a horizontal channel provided with sources of heat at constant temperature, which simulate hot electronic components. The transport equations for continuity, momentum, and energy are solved with finite volume approach using the SIMPLE algorithm. The effective thermal conductivity and the dynamic viscosity of the nanofluid are calculated using, respectively, the Maxwell-Garnett and Brinkman model. The influence of the volume fraction of the nanoparticles 0%≤φ≤10%, Reynolds numbers 5≤Re≤75, the distance between the blocks 0≤d/H≤3, and the types of nanoparticles added (TiO2, Al2O3, CuO, Ag, Cu, and MgO) were investigated and discussed. It emerges from this simulation that the heat transfer increases with the increase in the volume fraction of the nanoparticles and the Reynolds number and decreases with the augmentation of separation distance between heated sources. Moreover, the study shows that the heat transfer is improved by 20% at a solid volume fraction of 10% of Cu nanoparticles.

Numerical Study of Natural Convection in Vertical Cylindrical Annular Enclosure Filled with Cu-Water Nanofluid under Magnetic Fields

2019 ◽  
Vol 392 ◽  
pp. 123-137 ◽  
Author(s):  
Mohamed A. Medebber ◽  
Abderrahmane Aissa ◽  
Mohamed El Amine Slimani ◽  
Noureddine Retiel
Keyword(s):  
Natural Convection ◽  
Magnetic Fields ◽  
Volume Fraction ◽  
Numerical Study ◽  
Physical Parameters ◽  
Cold Temperatures ◽  
Simpler Algorithm ◽  
Wide Range ◽  
Nanoparticles Volume Fraction ◽  
Volume Method

The two dimensional study of natural convection in vertical cylindrical annular enclosure filled with Cu-water nanofluid under magnetic fields is numerically analyzed. The vertical walls are maintained at different uniform hot and cold temperatures, THand TC, respectively. The top and bottom walls of the enclosure are thermally insulated. The governing equations are solved numerically by using a finite volume method. The coupling between the continuity and momentum equations is effected using the SIMPLER algorithm. Numerical analysis has been carried out for a wide range of Rayleigh number (103≤Ra≤106), Hartmann number (1 ≤Ha≤100) and nanoparticles volume fraction (0 ≤φ≤0.08). The influence of theses physical parameters on the streamlines, isotherms and average Nusselt has been numerically investigated.

MODELING OF COMBINED RADIATIVE AND CONVECTIVE HEAT TRANSFER IN AN ENCLOSURE WITH A HEAT-GENERATING CONDUCTING BODY

2005 ◽  
Vol 02 (03) ◽  
pp. 431-450 ◽  
Author(s):  
A. MEZRHAB ◽  
H. BOUALI ◽  
C. ABID
Keyword(s):  
Numerical Study ◽  
Working Fluid ◽  
Heat Conducting ◽  
Exchange Effect ◽  
Nusselt Numbers ◽  
Radiation Exchange ◽  
Conducting Body ◽  
Simpler Algorithm ◽  
Cold Walls ◽  
Volume Method

In this paper, we present a numerical study of the radiation-natural convection interactions in a differentially heated enclosure, within which a centered, squared, heat-conducting body generates heat. A specifically developed numerical model based on the finite-volume method and the SIMPLER algorithm is used for the solution of the governing equations. The working fluid (air) is perfectly transparent to the radiation. The Rayleigh number Ra and the temperature-difference ratio ΔT* were varied parametrically. For Pr = 0.71, the results obtained show that: (i) The isotherms and streamlines are strongly affected by the radiation exchange at high Rayleigh numbers (Ra ≥ 106), (ii) the temperature of the inner body decreases under the radiation exchange effect, (iii) for a constant Ra, the average Nusselt number at the hot and cold walls (Nuh and Nuc) vary linearly with increasing ΔT*: Nuh decreases with ΔT* while Nuc increases with ΔT*. Furthermore, the radiation exchange increases both average Nusselt numbers Nuh and Nuc, especially at Ra ≥ 105, and consequently, [Formula: see text] increases.

Numerical Analysis of Mixed Convection of Nanofluids Inside a Vertical Channel

2016 ◽  
Vol 13 (03) ◽  
pp. 1650012 ◽  
Author(s):  
M. B. Akgül ◽  
M. Pakdemirli
Keyword(s):  
Mixed Convection ◽  
Single Phase ◽  
Volume Fraction ◽  
Solid Volume Fraction ◽  
Vertical Channel ◽  
Eulerian Model ◽  
Two Phase ◽  
Thermal Fields ◽  
Laminar Mixed Convection ◽  
Effective Particle

Laminar mixed convection of an Al[Formula: see text]O[Formula: see text]/water nanofluid inside a vertical channel is investigated numerically. Single-phase and two-phase Eulerian models are employed to analyze flow and thermal fields of the nanofluid in conjunction with the suitable expressions for the particle viscosity and effective particle thermal conductivity. The results of two-phase Eulerian model are compared with the single-phase model and with the published experimental data. Effects of the solid volume fraction, Reynolds number and Grashof number on the heat transfer performance of the nanofluid are investigated and discussed in detail.

scholarly journals Numerical Study of Heat Transfer by Natural Convection in Concentric Hexagonal Cylinders Charged with a Nanofluid

2022 ◽  
Vol 17 ◽  
pp. 19-28
Author(s):  
Taloub Djedid ◽  
Bouras Abdelkrim ◽  
Zied Driss
Keyword(s):  
Heat Transfer ◽  
Natural Convection ◽  
Volume Fraction ◽  
Numerical Study ◽  
Outer Cylinder ◽  
Boussinesq Approximation ◽  
Fixed Temperature ◽  
Nusselt Numbers ◽  
Volume Method ◽  
Rayleigh Numbers

In this document, a numerical study of the natural convection of steady-state laminar heat transfer in a horizontal ring between a heated hexagonal inner cylinder and a cold hexagonal outer cylinder. A Cu - water nanofluid traverses this annular space. The system of equations governing the problem was solved numerically by the fluent calculation code based on the finite volume method. Based on the Boussinesq approximation. The interior and exterior sides from the two cylinders are maintained at a fixed temperature. We investigated the impacts of various thermal Rayleigh numbers (103≤ Rat ≤2.5x105), and the volume fraction from the nanoparticles (0≤ Ø ≤0.12) on fluid flow and heat transfer performance. It is found that in high thermal Rayleigh numbers, a thin thermal boundary layer is illustrated at the flow that heavily strikes the ceiling and lower from the outer cylinder. In addition, the local and mean Nusselt number from a nanofluid are enhanced by enhancing the volume fraction of the nanoparticles.The results are shown within the figure of isocurrents, isotherms, and mean and local Nusselt numbers. Detailed results of the numerical has been compared with literature ones, and it gives a reliable agreement.

scholarly journals The Influence of Combined Turbulators on the Hydraulic-Thermal Performance and Exergy Efficiency of MWCNT-Cu/Water Nanofluid in a Parabolic Solar Collector: A Numerical Approach

2021 ◽  
Vol 9 ◽  
Author(s):  
Yacine Khetib ◽  
Ammar Melaibari ◽  
Radi Alsulami
Keyword(s):  
Solar Collector ◽  
Volume Fraction ◽  
Numerical Approach ◽  
Exergy Efficiency ◽  
Multiphase Model ◽  
Two Phase ◽  
Simpler Algorithm ◽  
Fluent Software ◽  
Parabolic Geometries ◽  
Volume Method

The present research benefits from the finite volume method in investigating the influence of combined turbulators on the thermal and hydraulic exergy of a parabolic solar collector with two-phase hybrid MWCNT-Cu/water nanofluid. All parabolic geometries are produced using DesignModeler software. Furthermore, FLUENT software, equipped with a SIMPLER algorithm, is applied for analyzing the performance of thermal and hydraulic, and exergy efficiency. The Eulerian–Eulerian multiphase model and k-ε were opted for simulating the two-phase hybrid MWCNT-Cu/water nanofluid and turbulence model in the collector. The research was analyzed in torsion ratios from 1 to 4, Re numbers from 6,000 to 18,000 (turbulent flow), and the nanofluid volume fraction of 3%. The numerical outcomes confirm that the heat transfer and lowest pressure drop are relevant to the Re number of 18,000, nanofluid volume fraction of 3%, and torsion ratio of 4. Furthermore, in all torsion ratios, rising Re numbers and volume fraction lead to more exergy efficiency. The maximum value of 26.32% in the exergy efficiency was obtained at a volume fraction of 3% and a torsion ratio of 3, as the Re number goes from 60,000 to 18,000.

scholarly journals Heat transfer analysis of nanofluid flow through backward facing step

2020 ◽  
Vol 307 ◽  
pp. 01010 ◽  
Author(s):  
Ahlem Boudiaf ◽  
Fetta Danane ◽  
Youb Khaled Benkahla ◽  
Walid Berabou ◽  
Mahdi Benzema ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Volume Fraction ◽  
Solid Volume Fraction ◽  
Thermal Characteristics ◽  
Heat Transfer Analysis ◽  
Backward Facing Step ◽  
Nanofluid Flow ◽  
Numerical Predictions ◽  
Flow Through ◽  
Volume Method

This paper presents the numerical predictions of hydrodynamic and thermal characteristics of nanofluid flow through backward facing step. The governing equations are solved through the finite volume method, as described by Patankar, by taking into account the associated boundary conditions. Empirical relations were used to give the effective dynamic viscosity and the thermal conductivity of the nanofluid. Effects of different key parameters such as Reynolds number, nanoparticle solid volume fraction and nanoparticle solid diameter on the heat transfer and fluid flow are investigated. The results are discussed in terms of the average Nusselt number and streamlines.

scholarly journals Natural Convection of Dusty Hybrid Nanofluids in an Enclosure Including Two Oriented Heated Fins

2019 ◽  
Vol 9 (13) ◽  
pp. 2673 ◽  
Author(s):  
Raizah
Keyword(s):  
Natural Convection ◽  
Volume Fraction ◽  
Simple Algorithm ◽  
Systems Of Equations ◽  
Nusselt Numbers ◽  
Pressure Distributions ◽  
Nanoparticles Volume Fraction ◽  
Hybrid Nanofluids ◽  
Volume Method ◽  
Present Simulation

In the current work, the natural convection of dusty hybrid nanofluids in an enclosure including two inclined heated fins has been studied via mathematical simulation. The inclined heated fins are arranged near to the enclosure center with variations on their orientations and lengths. The present simulation is represented by two systems of equations for the hybrid nanofluids that are dusty. The pressure distributions for the dusty phase and hybrid nanofluids phase are evaluated using a SIMPLE algorithm based on the finite volume method. The numerical results are examined using contours of the streamlines, isotherms for the hybrid nanofluids and velocity components for the dusty phase. In addition, the graphical illustrations for profiles of the local and average Nusselt numbers are presented. The main results reveal that an increase in the mixture densities ratio and dusty parameter reduces the rate of the heat transfer. Both the local and average Nusselt numbers are supported as the fins lengths increase regardless of the fins’ rotation. In addition, the nanoparticles volume fraction enhances the thermal boundary layer near the top wall.

scholarly journals Numerical Simulation of Fog Transport in a Horizontal Channel

2020 ◽  
Vol 330 ◽  
pp. 01033
Author(s):  
Nihel Grich ◽  
Walid Foudhil ◽  
Souad Harmand ◽  
Sadok Ben Jabrallah
Keyword(s):  
Volume Fraction ◽  
Numerical Study ◽  
Horizontal Channel ◽  
Comsol Multiphysics ◽  
Water Volume ◽  
Influence Of Water ◽  
Simulation Results ◽  
Water Volume Fraction ◽  
Phase Water ◽  
2D Numerical Model

Water spraying in exchanger systems is widely used to allow cooling and improving their performance. However, transfers within the spray mixture are difficult to express because the combined mass and heat are transferred between phases, which complicates the design of the spray systems. This article presents a numerical study of the influence of water volume fraction on the distribution of the temperature in a canal. A 2D numerical model of a horizontal channel was generated and the equations governing the continuous phases (air) and the dispersed phase (water) were developed. These equations were solved using Comsol multiphysics. A comparison of the simulation results and those of the experiment reveals an acceptable concordance.

scholarly journals Simulation of natural convection heat transfer using nanofluid in a concentric annulus

2017 ◽  
Vol 21 (3) ◽  
pp. 1275-1286 ◽  
Author(s):  
Keivan Fallah ◽  
Atena Ghaderi ◽  
Nima Sedaghatizadeh ◽  
Mohammad Borghei
Keyword(s):  
Natural Convection ◽  
Rayleigh Number ◽  
Volume Fraction ◽  
Solid Volume Fraction ◽  
Convection Heat Transfer ◽  
Thermal Characteristics ◽  
Width Ratio ◽  
Nusselt Numbers ◽  
Boltzmann Method ◽  
Gap Width

In the present study, natural convection of nanofluids in a concentric horizontal annulus enclosure has been numerically simulated using the lattice Boltzmann method. A water-based nanofluid containing Al2O3 nanoparticle has been studied. Simulations have been carried while the Rayleigh number ranges from 103 to 105 and solid volume fraction varies between 0 and 0.04. The effects of solid volume fraction of nanofluids on hydrodynamic and thermal characteristics such as average and local Nusselt numbers, streamlines, and isotherm patterns for different values of solid volume fraction, annulus gap width ratio and Rayleigh number are investigated and discussed in detail.

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