Lattice Boltzmann Simulation for Flow Inside Porous Open-Ended Medium with Partially Thermally Active Walls

2021 ◽  
Author(s):  
Raoudha Chaabane ◽  
Jemni Abdelmajid ◽  
Patrick Perré
Keyword(s):  
Free Convection ◽  
Lattice Boltzmann ◽  
Vertical Wall ◽  
Convection Heat Transfer ◽  
Flow Characteristics ◽  
Darcy Number ◽  
Left Wall ◽  
Nusselt Numbers ◽  
Lattice Boltzmann Simulation ◽  
Free Convection Heat

Abstract Free convection heat transfer and flow characteristics in an open-ended enclosure occupied with fluid saturated porous media is highlighted in the present paper. All numerical investigations are achieved using the mesoscopic approach Thermal Lattice Boltzmann Method (TLBM) by using the Darcy- Forchheiman model. The bottom and the top sides of the porous enclosure are thermally isolated with complete or partially heated vertical wall facing the opening sidewall. The partial slice of left wall of the enclosure with a fixed heating length as (H /3), is isothermally heated at the middle, top and bottom locations. However, right side is open to the ambient physical conditions. The influences of partial heating location on free convection characteristics, namely isotherms, streamlines, centerline variations of horizontal and vertical, average and local Nusselt numbers are explored for Darcy number of 0.01, porosity of 0.4, Rayleigh number of =106 and unity Prandtl number.

The coupled lattice Boltzmann simulation of free convection in a finned L-shaped cavity filled with nanofluid

2019 ◽  
Vol 30 (3) ◽  
pp. 1478-1496
Author(s):  
Peng Zhang ◽  
Muhammad Aqeel Ashraf ◽  
Zhenling Liu ◽  
Wan-Xi Peng ◽  
David Ross
Keyword(s):  
Free Convection ◽  
Lattice Boltzmann Method ◽  
Entropy Generation ◽  
Lattice Boltzmann ◽  
Convection Heat Transfer ◽  
Numerical Approach ◽  
Content Type ◽  
Lattice Boltzmann Simulation ◽  
Free Convection Heat ◽  
Boltzmann Method

Purpose This paper aims to investigate the free convection, heat transfer and entropy generation numerically and experientially. A numerical/experimental investigation is carried out to investigate the free convection hydrodynamically/thermally and entropy generation. Design/methodology/approach The coupled lattice Boltzmann method is used as a numerical approach which keeps the significant advantages of standard lattice Boltzmann method with better numerical stability. On the other hand, the thermal conductivity and dynamic viscosity are measured using modern devices in the laboratory. Findings Some correlations based on the temperature at different nanofluid concentration are derived and used in the numerical simulations. In this regard, the results will be accurate with respect to using theoretical properties of nanofluid, and close agreements will be detected between present results and the previous numerical and experimental works. The numerical investigation is done under the effect of Rayleigh number (103 < Ra < 106), volume concentration of nanofluid (?? = 0.5, 1, 1.5, 2, 2.5 and 3%) and thermal configuration of the cavity (Cases A, B, C and D). Originality/value The originality of the present work lies in coupling of the lattice Boltzmann method with experimental observations to analyse the free convection in a cavity.

Modeling of Free Convection Heat Transfer to a Supercritical Fluid in a Square Enclosure by the Lattice Boltzmann Method

2010 ◽  
Vol 133 (2) ◽  
Author(s):  
Mostafa Varmazyar ◽  
Majid Bazargan
Keyword(s):  
Heat Transfer ◽  
Free Convection ◽  
Supercritical Fluid ◽  
Finite Volume ◽  
Lattice Boltzmann ◽  
Convection Heat Transfer ◽  
Convection Heat ◽  
Square Enclosure ◽  
Free Convection Heat ◽  
Boltzmann Method

During the last decade, a number of numerical computations based on the finite volume approach have been reported, studying various aspects of heat transfer near the critical point. In this paper, a lattice Boltzmann method (LBM) has been developed to simulate laminar free convection heat transfer to a supercritical fluid in a square enclosure. The LBM is an ideal mesoscopic approach to solve nonlinear macroscopic conservation equations due to its simplicity and capability of parallelization. The lattice Boltzmann equation (LBE) represents the minimal form of the Boltzmann kinetic equation. The LBE is a very elegant and simple equation, for a discrete density distribution function, and is the basis of the LBM. For the mass and momentum equations, a LBM is used while the heat equation is solved numerically by a finite volume scheme. In this study, interparticle forces are taken into account for nonideal gases in order to simulate the velocity profile more accurately. The laminar free convection cavity flow has been extensively used as a benchmark test to evaluate the accuracy of the numerical code. It is found that the numerical results of this study are in good agreement with the experimental and numerical results reported in the literature. The results of the LBM-FVM (finite volume method) combination are found to be in excellent agreement with the FVM-FVM combination for the Navier–Stokes and heat transfer equations.

Lattice Boltzmann simulation of fluid flow and heat transfer in a parallel-plate channel with transverse rectangular cavities

2017 ◽  
Vol 28 (03) ◽  
pp. 1750042 ◽  
Author(s):  
Rasul Mohebbi ◽  
Hanif Heidari
Keyword(s):  
Heat Transfer ◽  
Aspect Ratio ◽  
Lattice Boltzmann ◽  
Convection Heat Transfer ◽  
Numerical Code ◽  
Nusselt Numbers ◽  
Flow And Heat Transfer ◽  
Lattice Boltzmann Simulation ◽  
Smooth Channel ◽  
Boltzmann Method

The aim of this paper is investigating the forced convection heat transfer in a channel with transverse rectangular cavities using the lattice Boltzmann method (LBM) which is not available in the literature yet. The effects of the Reynolds number (100–400), cavity aspect ratio ([Formula: see text], 0.5, 1.0), distance of cavities from each other ([Formula: see text]) in fixed depth of cavity ([Formula: see text]) on the velocity and temperature profiles are studied. Moreover, the flow patterns such as deflection and re-circulation zone inside the cavities are obtained. The local and averaged Nusselt numbers on the channel walls are achieved. The results show that the channel with cavities achieves heat transfer enhancements relative to the smooth channel. For the constant cavity aspect ratio, the maximum value of averaged Nusselt number in the channel is obtained in the case of [Formula: see text]. Heat transfer to the working fluids increases significantly by increasing the aspect ratio. The existed results are used to ascertain the validity of the numerical code and excellent agreement between results was found.

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