Modeling of Gas‐Particle Turbulent Flow in Spout‐Fluid Bed by Computational Fluid Dynamics with Discrete Element Method

Abstract

Gas and solid turbulent flow in a cylindrical spout-fluid bed with conical base were investigated by incorporating various gas-particle interaction models for two-way coupling simulation of discrete particle dynamics. The gas flow field was computed by a k-e two-equation turbulent model, the motion of solid particles was modeled by the discrete element method. Drag force, contact force, Saffman lift force, Magnus lift force and gravitational force acting on individual particles were considered in the mathematical models. Calculations on the cylindrical spout-fluid bed with an inside diameter of 152 mm, a height of 700 mm, a conical base of 60°and the ratio of void area of 3.2 % were carried out. Based on the simulation, the gas-solid flow patterns at various spouting gas velocities are presented. Besides, the changes in particle velocity, particle concentration, collision energy, particle and gas turbulent intensities at different proportions of fluidizing gas to total gas flow are discussed.

Importance of Physical and Physiological Parameters in Simulated Particle Transport in the Alveolar Zone of the Human Lung

“…Moreover, the inter-particle contact forces resulting from the DEM approach are determined by the F C,ij force. The governing equations for forces are described elsewhere [14][15][16][17].…”

Numerical investigations of a pseudo-2D spout fluidized bed with draft plates using a scaled discrete particle model

“…Since the development of the spout fluidized bed by Chatterjee (1970), a number of modifications were suggested to improve the bed performance. These modifications involve different geometrical configurations such as rectangular (Link et al, 2008), conical bottom (Zhong et al, 2006;Ren et al, 2011), slotted rectangular, multiple and elevated spout fluidized beds (van Buijtenen et al, 2011a(van Buijtenen et al, , 2012. One of the significant modifications includes insertion of a draft tube inside the bed, which results in an improved performance by restricting the lateral particle flow.…”

Fluid Dynamics of a Sand‐Biomass Mixture in a Spouted‐Bed Reactor for Fast Pyrolysis

“…Tests with mixtures of glass beads of different diameters [23] in spouted beds have demonstrated that a higher proportion of the large-size component concentrates in the upper part of the bed. With respect to particles of the same size and different densities, Santos [24] observed that lighter particles concentrate at the top of the bed and near the wall, probably due the low elasticity of the collision between light particles [29,30].…”