A multi-block lattice Boltzmann method for viscous fluid flows

It is known that the Lattice Boltzmann Method is not very effective when it is being used for the high speed compressible viscous flows; especially complex fluid flows around bodies. Different reasons have been reported for this unsuccessfulness; Lacking in required isotropy in the employed lattices and the restriction of having low Mach number in Taylor expansion of the Maxwell Boltzmann distribution as the equilibrium distribution function, might be mentioned as the most important ones. In present study, a new numerical method based on Li et al. scheme is introduced which enables the Lattice BoltzmannMethod to stably simulate the complex flows around a 2D circular cylinder. Furthermore, more stable implementation of boundary conditions in Lattice Boltzmann method is discussed.

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Numerical Investigation of Flow Over an Airfoil by the Lattice Boltzmann Method

Volume 1: Advances in Aerodynamics ◽

10.1115/imece2013-62386 ◽

2013 ◽

Author(s):

Felipe A. Valenzuela ◽

Amador M. Guzmán ◽

Andrés J. Díaz

Keyword(s):

Lattice Boltzmann Method ◽

Lattice Boltzmann ◽

Preliminary Investigation ◽

Computational Cost ◽

Fluid Flows ◽

Laminar Flows ◽

Navier Stokes ◽

Laminar Separation ◽

Refinement Method ◽

Boltzmann Method

During the last years the aerodynamics characteristics of airfoils have been studied solving numerically the Navier-Stokes (NS) equations. These calculations require a significant computational cost due to both the second order and the nonlinear characteristics of the NS partial differential equations. Therefore, efforts have been devoted to reduce this cost and increase the accuracy of the numerical methods. The Lattice-Boltzmann Method (LBM) has become a great alternative to simulate this problem and a variety of fluid flows. In this method, the convective operator is linear and the pressure is calculated directly by the equation of state without implementing iterative methods. This work represents a preliminary investigation of a laminar flow over airfoils under low Reynolds number conditions (Re = 500). Solutions are obtained using a Multi-Block mesh refinement method. In order to validate the computational code, calculations are performed on a SD7003 airfoil at an angle of attack of 4° and 30°, which corresponds to the available numerical and experimental results. The results of this study agree well with previous experimental and numerical studies demonstrating the capabilities of the LBM to simulate accurately laminar flows over airfoils as well as capturing and predicting the laminar separation bubbles.

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Coupling molecular dynamics and pseudopotential lattice Boltzmann method with non-ideal equation of state for microscopic fluid flows

Heat Transfer Research ◽

10.1615/heattransres.2021041645 ◽

2021 ◽

Author(s):

Zi-Xiang Tong ◽

Ming-Jia Li ◽

Dong Li

Keyword(s):

Molecular Dynamics ◽

Equation Of State ◽

Lattice Boltzmann Method ◽

Lattice Boltzmann ◽

Fluid Flows ◽

Boltzmann Method

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A Meshfree-Based Lattice Boltzmann Approach for Simulation of Fluid Flows Within Complex Geometries

Advances in Computer and Electrical Engineering - Analysis and Applications of Lattice Boltzmann Simulations ◽

10.4018/978-1-5225-4760-0.ch006 ◽

2018 ◽

pp. 188-222 ◽

Cited By ~ 1

Author(s):

Sonam Tanwar

Keyword(s):

Lattice Boltzmann Method ◽

Lattice Boltzmann ◽

Moving Boundary ◽

Fluid Flows ◽

Computational Domain ◽

Time Step ◽

Boundary Problems ◽

Complex Process ◽

Element Free ◽

Boltzmann Method

This chapter develops a meshless formulation of lattice Boltzmann method for simulation of fluid flows within complex and irregular geometries. The meshless feature of proposed technique will improve the accuracy of standard lattice Boltzmann method within complicated fluid domains. Discretization of such domains itself may introduce significant numerical errors into the solution. Specifically, in phase transition or moving boundary problems, discretization of the domain is a time-consuming and complex process. In these problems, at each time step, the computational domain may change its shape and need to be re-meshed accordingly for the purpose of accuracy and stability of the solution. The author proposes to combine lattice Boltzmann method with a Galerkin meshfree technique popularly known as element-free Galerkin method in this chapter to remove the difficulties associated with traditional grid-based methods.

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