摘要：针对稀相气力输送能耗和粉料破碎率高以及稳定性差等缺陷, 在计算流体力学软件FLUENT上, 选择Euler双流体模型与k-ε湍流模型对粮食颗粒在水平变径管内的密相流体输送进行数值模拟, 并将仿真数据与实验结果相论证。发现湍流对两相流动过程中的稳定性有较大影响;分析管道内颗粒浓度、输送气体速度和压力损失随管道长度的变化规律, 探讨密相气力输送主要参数间的影响关系, 得出气流速度、压力损失会随着变径长度的增大分别下降15%、20%。

关键词：密相气力输送；气固两相流；水平变径管；粮食颗粒；数值模拟

Abstract：In order to solve the defects of high energy consumption, high breakage rate and poor stability of the dilute phase pneumatic conveying of grain particles. Numerical simulation was conducted on the dense phase fluid transport of grain in the horizontal tube by using Euler double fluid and k-εmodel on the platform of computational fluid dynamics software FLUENT. The influence of turbulence was found when the material flows in the gas-solid two-phase flow by comparing the simulation results with the experimental results. The change rule of performance parameters such as particle concentration distribution, velocity of conveying gas and pressure loss in pipeline due to the use of variable diameter pipe were analyzed.The flow characteristics of dense phase pneumatic conveying were discussed. It is concluded that the loss of air velocity and pressure will decrease by 15% and 20% respectively with the increase of the length of the variable diameter.

Keywords： dense phase pneumatic conveying； gas -solid two -phase flow； horizontal stepped pipeline； grain particles； numerical simulation