Modeling 3D Numerical Movable Bed based on LBM and its Application to the Analysis of Bed-Load Layer

Abstract

The three-dimensional lattice Boltzmann method (LBM) is used to simulate the behavior of bed-load layer in open channel shear flow. The 3D LBM for particle-fluid suspensions originally developed by Ladd (1994) has been extended to free-surface flow and to higher Reynolds number regime. The SGS turbulence term based on Smagorinsky model is also included in the LBM flow simulation. The present simulation predicts well the behavior of each particle in the bed-load layer both in saltation and sheetflow regimes. Results of the present simulation for the height and length of saltation, the bed-load velocity and the existing probability density agree fairly well with the experimental data from Gotoh et al. (1994).

3d LBM Numerical Simulation of Mixed Sand Sorting Under Oscillatory Flows and Progressive Waves

“…Sub Grid Smagorinsky (SGS) turbulence model is rather easily applied by adding the modified total kinematic viscosity to the collision term of the general Lattice Boltzmann Equation with BGK approximation (He et al 2013). Specifically, the eddy viscosity coefficient t ν of SGS turbulence term is added to the normal kinematic viscosity coefficient ν , resulting in a total kinematic viscosity…”

“…In their model, DEM is applied for the motion of particles and discrete Boltzmann equation is used for the solution of fluid motion. He et al (2013) expanded Ladd's LBM for particle-fluid suspension with free surface flow and SGS turbulence model to study the sediment transport of uniform particles under open channel flows. In this paper, the 3D numerical movable bed model based on LBM (He et al 2013) is applied to investigate the processes of mixed-grain-size sediments under both symmetric sinusoidal oscillatory flows and asymmetric fluid particle motion based on cnoidal wave theory.…”

“…He et al (2013) expanded Ladd's LBM for particle-fluid suspension with free surface flow and SGS turbulence model to study the sediment transport of uniform particles under open channel flows. In this paper, the 3D numerical movable bed model based on LBM (He et al 2013) is applied to investigate the processes of mixed-grain-size sediments under both symmetric sinusoidal oscillatory flows and asymmetric fluid particle motion based on cnoidal wave theory. The concentration centroids of mixed-grain-size sediments under symmetric oscillatory flow are compared to the experiment results of Harada and Gotoh (2008).…”

Drift Behavior of Automobiles in Tsunami

“…According to Ladd's 6) LBM model for particle suspension, the fluid-particle interaction can be simulated by the exchange of momentum, due to the application of link-bounce-back scheme for the movable solid particles in the fluid. The authors 7) have extended Ladd's LBM model for particle suspension with free surface and SGS turbulence model. In this paper, it is further modified to satisfy the rigid boundary conditions of automobiles with irregular shape.…”

“…The DF of a moving automobile can be shown as Further details of parameters in the above equations together with free surface condition and turbulence term can be found in the authors' paper 7) .…”