供料器内颗粒碰撞条件下的两相流压力特性仿真分析

Simulation analysis of the pressure characteristics of two-phase flow in feeding device based on particle collision

供料器作为气力输送系统中料气混合的关键部位,其内部产生的颗粒碰撞会引起压力损失的变化,从而影响整个系统的输送效率。基于供料器内颗粒碰撞条件下的两相流具有颗粒离散相和气体连续相的双重性质,利用计算流体力学-离散单元法(Computational Fluid Dynamics-Discrete Element Method,CFD-DEM)耦合方法,借助Fluent软件和EDEM软件对传统落料式供料器内的气固两相流进行耦合数值仿真,重点研究了颗粒碰撞条件下的压力分布特性。通过与CFD仿真结果对比,分析了颗粒碰撞条件下的压力特性变化规律。结果表明:供料器内的颗粒碰撞主要在气固混合阶段影响压力变化特性,且会降低管道内的压力损失,促进出口截面动压分布的均匀化,有利于提高管道输送效率。

The feeding device is the key part of the gas-solid mixing in pneumatic conveying system. The change of the pressure loss and the conveying efficiency of the whole system will be caused by particle collision in feeding device. Based on the condition that two-phase in feeding device under the particle collision has dual nature of particle discrete phase and gas continuous phase, a coupling numerical simulation of the gas-solid two-phase flow in a feeding device has been perforemed with the help of the Flu- ent and EDEM software by using the CFD-DEM coupling method,focusing on the research of the pressure distribution characteris- tics under the particle collision. By comparing with the simulation results of CFD, analyzes the variation law of pressure character- istics under the condition of particle collision. The results show that the particle collision in feeding device mainly affect the char- acteristics of pressure changes in the gas-solid mixing stage, and will reduce the pressure loss in the pipeline, promote the uniform of outlet section dynamic pressure distribution, and improve the overall conveying efficiency.