When using a lattice Boltzmann method on an unbounded (or very large) domain one has to confine this spatial domain to a computational domain. This is realized by introducing so-called artificial boundary conditions. Until recently, characteristic boundary conditions for the Euler equations were considered and adapted to the lattice Boltzmann method. In this work we propose novel discrete artif...

abstract: since the field of micro electromechanical systems (mems) continues to grow, the flow in micro devices have become an area that receives a significant attention. the microscopic flows are usually characterized by the knudsen number (kn). when the characteristic size of the particle decreases down to a value comparable to the mean free path of the molecules, the continuum assumption fa...

in this paper, fluid flow between two parallel flat plates that are partially filled with two-dimension porous media is investigated numerically using single relaxation time (srt) lattice boltzmann method (lbm) at pore scale. the considered obstacles are random, circular, rigid and granular with uniform diameters. single component and single-phase viscous newtonian fluid are considered as worki...

In this paper, the lattice Boltzmann method is reviewed for specific applications to numerical simulation of multiphase flow problems. A thorough literature review regarding the multi-phase lattice Boltzmann method was conducted with special focus on flows with large density and viscosity ratios between the two phases. A multiphase model with the capability of handling large-density-ratios is c...

Lifting operators play an important role in starting a kinetic Boltzmann model from given macroscopic information. The macroscopic variables need to be mapped to the distribution functions, mesoscopic variables of the Boltzmann model. A well-known numerical method for the initialization of Boltzmann models is the Constrained Runs algorithm. This algorithm is used in literature for the initializ...

Some rigorous results on discrete velocity models are briefly reviewed and their ramifications for the lattice Boltzmann equation (LBE) are discussed. In particular, issues related to thermodynamics andH -theorem of the lattice Boltzmann equation are addressed. It is argued that for the lattice Boltzmann equation satisfying the correct hydrodynamic equations, there cannot exist an H -theorem. N...

Some rigorous results on discrete velocity models are briefly reviewed and their ramifications for the lattice Boltzmann equation (LBE) are discussed. In particular, issues related to thermodynamics and H-theorem of the lattice Boltzmann equation are addressed. It is argued that for the lattice Boltzmann equation satisfying the correct hydrodynamic equations, there cannot exist an H-theorem. Ne...

1. Abstract This paper presents a topology optimization method using the lattice Boltzmann method for the design of a flow channel considering two-phase fluid flows. This approach enables the design of fluidic devices such as two-phase microchannels that achieve a desired flow with maximal performances such as mixing and reaction, and extraction efficiencies. The optimization problems are formu...

Article history: Received 9 August 2016 Received in revised form 8 November 2016 Accepted 16 January 2017 Available online 18 January 2017