THERMAL LATTICE BOLTZMANN SIMULATION OF VISCOUS FLOW IN A SQUARE CAVITY

The 13-speed thermal lattice Bhatnagar–Gross–Krook model on hexagonal lattice is a single relaxation time model with an adjustable parameter λ which makes the Prandtl number tunable. This model maintains the simplicity of the lattice Boltzmann method (LBM) and is also suitable for various thermal fluids. In this paper, it is applied to simulations of the lid-driven flow in a square cavity at a wide range of Reynolds numbers. Numerical experiments show that this model can give the same accurate results as those by the conventional numerical methods.

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Thermal Lattice Boltzmann Simulation of Rarefied Gas Flows in Nanochannels for Wide Range of Knudsen Number

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.403-408.5313 ◽

2011 ◽

Vol 403-408 ◽

pp. 5313-5317

Author(s):

A.H. Meghdadi Isfahani ◽

A. Soleimani

Keyword(s):

Lattice Boltzmann ◽

Rarefied Gas ◽

Gas Flows ◽

Rarefied Gas Flows ◽

Knudsen Numbers ◽

Lattice Boltzmann Simulation ◽

Wide Range ◽

Flow Through ◽

Boltzmann Method ◽

Thermal Lattice Boltzmann

Using a modified Lattice Boltzmann Method (LBM), developing thermal flow through micro and nano channels has been modeled. Based on the improving of the dynamic viscosity and thermal conductivity, an effective relaxation time formulation is proposed which is able to simulate wide range of Knudsen numbers, Kn,. The results show that in spite of the standard LBM, the temperature distributions and the local Nusselt number obtained from this modified thermal LBM, agree well with the other numerical and empirical results in a wide range of Knudsen numbers.

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Lattice Boltzmann simulation of two-sided lid-driven flow in deep cavities

Acta periodica technologica ◽

10.2298/apt1546157l ◽

2015 ◽

pp. 157-168

Author(s):

Natasa Lukic ◽

Predrag Tekic ◽

Jelena Radjenovic ◽

Ivana Sijacki

Keyword(s):

Aspect Ratio ◽

Flow Pattern ◽

Lattice Boltzmann ◽

Reynolds Numbers ◽

Critical Aspect ◽

Symmetric Flow ◽

Primary Vortex ◽

Lattice Boltzmann Simulation ◽

Boltzmann Method ◽

Deep Cavities

The present study is concerned with two-sided lid-driven incompressible flow in rectangular, deep cavities applying lattice Boltzmann method. After validating the code for the square cavity, solutions for cavities with an aspect ratio 1.5 and 4 were obtained for the Reynolds numbers of 100, 400, 1000 and 3200. The influence of the Reynolds number and aspect ratio on the flow pattern and on the characteristics of vortices inside the cavity was studied. Symmetric flow pattern was obtained for all investigated cases. The middle of the cavity is mostly influenced by the increase in the aspect ratio. Critical aspect ratio, at which the birth of a primary vortex in the middle of the cavity takes place, was determined to be between 2.7 and 2.725.

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Lattice Boltzmann Simulation of Flow and Heat Transfer Characteristics in a Symmetrically Bifurcated Microchannel

Heat Transfer, Volume 2 ◽

10.1115/imece2004-62216 ◽

2004 ◽

Author(s):

Keqiang Xing ◽

Yong Tao

Keyword(s):

Heat Transfer ◽

Lattice Boltzmann ◽

Constant Heat Flux ◽

Lattice Boltzmann Model ◽

Straight Tube ◽

Lattice Boltzmann Simulation ◽

Flux Boundary Conditions ◽

Boltzmann Method ◽

Thermal Lattice Boltzmann ◽

Transfer Problems

The lattice Boltzmann method (LBM) as a relatively new numerical scheme has recently achieved considerable success in simulating fluid flows and associated transport phenomena. However, application of this method to heat transfer problems has been at a stage of infancy. In this work, a thermal lattice Boltzmann model is employed to simulate a two-dimensional, steady flow in a symmetric bifurcation under constant temperature and constant heat flux boundary conditions. The bifurcation effects on the heat transfer and fluid flow are investigated and comparisons are made with the straight tube. Also, different bifurcation angles are simulated and the results are compared with the work of the other researchers.

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Aerodynamics Research of Thermal Fluid Circulation in a Heated Cavity

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.668-669.326 ◽

2014 ◽

Vol 668-669 ◽

pp. 326-330

Author(s):

Guang Zhao

Keyword(s):

Lattice Boltzmann ◽

Area Ratio ◽

Circulation Rate ◽

Fluid Circulation ◽

Square Cavity ◽

Heating Source ◽

Mass And Heat Transfer ◽

Boltzmann Method ◽

Thermal Lattice Boltzmann ◽

Rayleigh Numbers

In this paper, numerical simulation of natural convection in a closure square cavity with heating source on the basement is carried out using thermal lattice Boltzmann method. The purpose of this work is to analysis the physics of mass and heat transfer in such a condition. For different Rayleigh numbers, the relative heating area ratio is changed in the range of 0.1-1.0, correspondingly. It is found that the flow pattern is symmetrical for increases from 103to 106, and the boundary layers at low temperature become thinner, also the circulation rate is higher. For a special Rayleigh number, is as a monotone increment function of relative heating area ratio, and the value of which almost increases linearly when the area is below 0.8, and then reach to its maximum exponentially.

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Lattice Boltzmann Simulation of Flow and Heat Transfer Characteristics in a Symmetric Bifurcation

Heat Transfer: Volume 2 ◽

10.1115/ht2005-72629 ◽

2005 ◽

Author(s):

K. Q. Xing ◽

Y.-X. Tao

Keyword(s):

Heat Transfer ◽

Lattice Boltzmann ◽

Passive Scalar ◽

Heat Fluxes ◽

Lattice Boltzmann Model ◽

Lattice Boltzmann Simulation ◽

Flux Boundary Conditions ◽

Constant Wall Heat Flux ◽

Boltzmann Method ◽

Thermal Lattice Boltzmann

The lattice Boltzmann method (LBM) originates from the discrete kinetic theory and has been applied for simulation of various kinds of fluid flows under different conditions. In this paper, a passive-scalar-based thermal lattice Boltzmann model is employed to simulate the steady flow in a symmetric bifurcation channel under constant wall heat flux boundary conditions. The bifurcation effects on the heat transfer and fluid flow are thoroughly investigated under different Reynolds numbers, wall heat fluxes and bifurcation angles. The results are compared with the commercial software output. A useful discussion about how to transfer from lattice units to actual physical units is also presented.

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Lattice Boltzmann simulation of Rayleigh-Benard convection in enclosures filled with Al2O3-water nanofluid

Thermal Science ◽

10.2298/tsci171023038c ◽

2018 ◽

Vol 22 (Suppl. 2) ◽

pp. 535-545

Author(s):

Weihua Cai ◽

Zhifeng Zheng ◽

Changye Huang ◽

Yue Wang ◽

Xin Zheng ◽

...

Keyword(s):

Heat Transfer ◽

Lattice Boltzmann ◽

Convection Heat Transfer ◽

Bénard Convection ◽

Lattice Boltzmann Simulation ◽

Benard Convection ◽

Wide Range ◽

Boltzmann Method ◽

Rayleigh Benard Convection ◽

Rayleigh Benard

In order to clarify the controversies for the role of nanoparticles on heat transfer in natural convection, lattice Boltzmann method is used to investigate Rayleigh-Benard convection heat transfer in differentially-heated enclosures filled with Al2O3-water nanofluids. The results for streamline and isotherm contours, vertical velocity, and temperature profiles as well as the local and average Nusselt number are discussed for a wide range of Rayleigh numbers and nanoparticle volume fractions (0 ? ? ? 5%). The results show that with the increase of Rayleigh number and nanoparticles loading, Nuave increases. It is suggested that the addition of nanoparticles can enhance the heat transfer in Rayleigh-Benard convection.

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A New Relaxation Time Model for Lattice Boltzmann Simulation of Nano Couette Flows in Wide Range of Flow Regimes

Journal of Applied Fluid Mechanics ◽

10.29252/jafm.12.06.29615 ◽

2019 ◽

Vol 12 (6) ◽

pp. 1781-1790

Author(s):

S. Ghatreh Samani ◽

A. H. Meghdadi Isfahani ◽

◽

Keyword(s):

Relaxation Time ◽

Lattice Boltzmann ◽

Flow Regimes ◽

Time Model ◽

Lattice Boltzmann Simulation ◽

Wide Range

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Lattice Boltzmann simulation of flow over a circular cylinder at moderate Reynolds numbers

Thermal Science ◽

10.2298/tsci110908093a ◽

2014 ◽

Vol 18 (4) ◽

pp. 1235-1246 ◽

Cited By ~ 6

Author(s):

Perumal Arumuga ◽

Gundavarapu Kumar ◽

Anoop Dass

Keyword(s):

Reynolds Number ◽

Circular Cylinder ◽

Lattice Boltzmann ◽

Reynolds Numbers ◽

Channel Length ◽

Incompressible Viscous Flow ◽

Lattice Boltzmann Simulation ◽

Flow Features ◽

Boltzmann Method ◽

Steady And Unsteady Flows

This work is concerned with Lattice Boltzmann computation of two-dimensional incompressible viscous flow past a circular cylinder confined in a channel. Computations are carried out both for steady and unsteady flows and the critical Reynolds number at which symmetry breaks and unsteadiness sets in is predicted. Effects of Reynolds number, blockage ratio and channel length are studied in some details. All the results compare quite well with those computed with continuum-based methods, demonstrating the ability and usefulness of the Lattice Boltzmann Method (LBM) in capturing the flow features of this interesting and fluid-mechanically rich problem.

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