LES of Fuel Jet in Cross-Flow Using Lattice Boltzmann Method

Large eddy simulation (LES) is performed on a jet issued normally into a cross-flow using lattice Boltzmann method (LBM) and multiple graphic processing units (multi-GPUs) to study the flow characteristics of jets in cross-flow (JICF). The simulation with 8 1.50?10 grids is fulfilled with 6 K20M GPUs. With large-scaled simulation, the secondary and tertiary vortices are captured. The features of the secondary vortices and the tertiary vortices reveal that they have a great impact on the mixing between jet flow and cross-flow. The qualitative and quantitative results also indicate that the evolution mechanism of vortices is not constant, but varies with different situations. The hairpin vortex under attached jet regime originates from the boundary layer vortex of cross-flow. While, the origin of hairpin vortex in detached jet is the jet shear-layer vortex. The mean velocities imply the good ability of LBM to simulate JICF and the large loss of jet momentum in detached jet caused by the strong penetration. Besides, in our computation, a high computational performance of 1083.5 MLUPS is achieved.

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A Lattice Boltzmann Simulation of Cross-Flow Around Four Cylinders in a Square Arrangement

ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis, Volume 4 ◽

10.1115/esda2010-24628 ◽

2010 ◽

Author(s):

J. Abolfazli Esfahani ◽

A. R. Vasel Be Hagh

Keyword(s):

Reynolds Number ◽

Lattice Boltzmann Method ◽

Finite Volume Method ◽

Finite Volume ◽

Lattice Boltzmann ◽

Cross Flow ◽

Spacing Ratio ◽

Volume Method ◽

Boltzmann Method ◽

Four Cylinders

The purpose of the present work is simulating cross flow around four cylinders in a square configuration by using a Lattice Boltzmann method. The effective parameters such as Reynolds number and spacing ratio L/D are chosen on the basis of former researches of other authors which have been done experimentally or by using traditional numerical schemes like finite volume method to provide the opportunity for comparing Lattice Boltzmann results with those obtained from experimental and CFD studies. Hence, the Reynolds number is set at Re = 100 and the spacing ratio is chosen to be 1.5, 2.5, 3.5, 4.5. It is shown that final results such as flow pattern, velocity and vorticity field are in accordance with those obtained by former researchers via experimental efforts or by use of finite volume method. This good agreement beside other important qualities such as efficient code, not having mesh tangling associated with other common numerical approaches, high convergence speed and nondimensional velocity and pressure field indicate this fact that in comparison with other numerical methods, Lattice Boltzmann method is very capable of analyzing a broad variety of fluid flows.

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Numerical Study on Cross-Flow around Three Cylinders Using Lattice Boltzmann Method

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.525.311 ◽

2014 ◽

Vol 525 ◽

pp. 311-315

Author(s):

Xiang Cui Lv ◽

Wei Zhang ◽

Dian Xin Zhang

Keyword(s):

Reynolds Number ◽

Lattice Boltzmann Method ◽

Vortex Shedding ◽

Lattice Boltzmann ◽

Numerical Study ◽

Cross Flow ◽

Evolution Process ◽

Spacing Ratio ◽

The Right ◽

Boltzmann Method

The flow around three cylinders in isosceles left-triangle and right-triangle configurations at Reynolds number of 200 are investigated using lattice Boltzmann method (LBM). Vortex shedding pattern and evolution process in the wake of each cylinder in the two cases are analyzed with a spacing ratio of 4. Results show that the flow pattern in the right-triangle configuration is symmetrical and the vortex shedding is anti-phase. Meanwhile, vortex shedding in-phase is observed in the left-triangle configuration which is due to the effect of the periodical vortex shedding behind upstream cylinder. The evolution process of vortex in the wakes of the cylinders for left-triangle configuration is simulated numerically.

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Numerical Simulation of Cross-Flow around Four Cylinders in a Square Configuration Using Lattice Boltzmann Method

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.405-408.3259 ◽

2013 ◽

Vol 405-408 ◽

pp. 3259-3262 ◽

Cited By ~ 1

Author(s):

Wei Zhang ◽

Hui Hua Ye ◽

Jian Hua Tao

Keyword(s):

Numerical Simulation ◽

Reynolds Number ◽

Lattice Boltzmann Method ◽

Vortex Shedding ◽

Lattice Boltzmann ◽

Cross Flow ◽

Spacing Ratio ◽

Square Configuration ◽

Boltzmann Method ◽

Four Cylinders

The flow around four cylinders in a square configuration with a spacing ratio 4 and Reynolds number of 200 are investigated using lattice Boltzmann method for angles of incidence α=0 and 45º, respectively. The results show that no biased flow occurs and the flow pattern is symmetrical at α=0, and the vortex shedding exists after the upstream cylinders which is completely different from the experimental results. It is hard to explain the discrepancy at present. The phenomenon of vortex shedding in-phase observed in the experiment reappears in the numerical simulation at α=45º.

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Aeroacoustic simulation of a cross-flow fan using lattice Boltzmann method with a RANS model

INTER-NOISE and NOISE-CON Congress and Conference Proceedings ◽

10.3397/in-2021-1578 ◽

2021 ◽

Vol 263 (6) ◽

pp. 598-609

Author(s):

Kazuya Kusano ◽

Masato Furukawa ◽

Kenichi Sakoda ◽

Tomoya Fukui

Keyword(s):

Lattice Boltzmann Method ◽

Lattice Boltzmann ◽

Stokes Equations ◽

Computational Cost ◽

Cross Flow ◽

Pressure Rise ◽

Navier Stokes ◽

Immersed Boundary ◽

Boltzmann Method ◽

Cross Flow Fan

The present study developed an unsteady RANS approach based on the lattice Boltzmann method (LBM), which can perform direct aeroacoustic simulations of low-speed fans at lower computational cost compared with the conventional LBM-LES approach. In this method, the k-ω turbulence model is incorporated into the LBM flow solver, where the transport equations of k and ω are also computed by the lattice Boltzmann method, similar to the Navier-Stokes equations. In addition, moving boundaries such as fan rotors are considered by a direct-forcing immersed boundary method. This numerical method was validated in a two-dimensional simulation of a cross-flow fan. As a result, the simulation was able to capture an eccentric vortex structure in the rotor, and the pressure rise by the work of the rotor can be reproduced. Also, the peak sound of the blade passing frequency can be successfully predicted by the present method. Furthermore, the simulation results showed that the peak sound is generated by the interaction between the rotor blade and the flow around the tongue part of the casing.

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