This paper proposes a lattice Boltzmann scheme to simulate two-dimensionalfluid transients. A set of multi-scale equations, which characterize the relations between thelattice Boltzmann equation and its corresponding ...This paper proposes a lattice Boltzmann scheme to simulate two-dimensionalfluid transients. A set of multi-scale equations, which characterize the relations between thelattice Boltzmann equation and its corresponding macroscopic equations, were derived by using theChapman-Enskog expansion. Based on these multi-scale equations and the basic equations ofmultidimensional fluid transients, two special lattice Boltzmann models were established. Numericalsimulation of one-dimensional pressure wave transmission and reflection, two-dimensional wave cornerdiffraction and hydraulic transients in a concrete spiral case show that the Lattice BoltzmannMethod (LBM) is a feasible and promising approach to simulate multidimensional transient flows.展开更多
To improve the computational efficiency of Lattice Boltzmann Method (LBM), inthis paper, LBM with doule meshes is presented, whose basic ideology is borrowed from the FiniteDifference Method (FDM). Taking merits of bo...To improve the computational efficiency of Lattice Boltzmann Method (LBM), inthis paper, LBM with doule meshes is presented, whose basic ideology is borrowed from the FiniteDifference Method (FDM). Taking merits of both the coarse and fine meshes, the presented methodspeeds up the convergence, and increases the computational efficiency. Three numerical examples,two-dimensional Poiseuille flow, backward-facing step flow and flow in channel with a rectangularslot, are illustated, proving that time cost by double-mesh LBM is much less than that by commonlyused u-niform-mesh LBM, and the results obtained are correct and dependable.展开更多
文摘This paper proposes a lattice Boltzmann scheme to simulate two-dimensionalfluid transients. A set of multi-scale equations, which characterize the relations between thelattice Boltzmann equation and its corresponding macroscopic equations, were derived by using theChapman-Enskog expansion. Based on these multi-scale equations and the basic equations ofmultidimensional fluid transients, two special lattice Boltzmann models were established. Numericalsimulation of one-dimensional pressure wave transmission and reflection, two-dimensional wave cornerdiffraction and hydraulic transients in a concrete spiral case show that the Lattice BoltzmannMethod (LBM) is a feasible and promising approach to simulate multidimensional transient flows.
文摘To improve the computational efficiency of Lattice Boltzmann Method (LBM), inthis paper, LBM with doule meshes is presented, whose basic ideology is borrowed from the FiniteDifference Method (FDM). Taking merits of both the coarse and fine meshes, the presented methodspeeds up the convergence, and increases the computational efficiency. Three numerical examples,two-dimensional Poiseuille flow, backward-facing step flow and flow in channel with a rectangularslot, are illustated, proving that time cost by double-mesh LBM is much less than that by commonlyused u-niform-mesh LBM, and the results obtained are correct and dependable.
