基于气固多相耦合小麦旋流输送流场特性研究

Flow Field Characteristics of Wheat Cyclone Pneumatic Conveying System Based on Gas-solid Multi-phase Coupling

目的对比轴流式气力输送小麦与旋流气力输送小麦系统的能效。方法采用CFD-DEM对小麦颗粒在水平管道中以轴流式输送和旋流输送的过程进行仿真,多相流入射速度均为20 m/s,旋流输送外加5个补气管道,入射速度为30 m/s。通过仿真实验,对比轴流输送和旋流输送中小麦颗粒沉积状态、小麦颗粒速度、输送系统压降、系统能耗等指标。结果仿真结果表明,采用旋流输送明显优于轴流输送,颗粒螺旋前进,输送效果较优。经试验验证,与仿真结果一致。结论在同一工况下,旋流输送小麦可以有效抑制颗粒的沉降,颗粒分布均匀,可以有效减少与管道的摩擦,输送距离更远,系统的输送效率更高,运输效果良好。

The work aims to compare the energy efficiency of axial flow pneumatic conveying wheat system and cyclone pneumatic conveying wheat system.CFD-DEM was used to simulate the axial flow and cyclone conveying of wheat grains in the horizontal pipeline,the multi-phase inflow and injection velocity was 20 m/s,and the cyclone transportation plus five make-up air pipelines had an incident velocity of 30 m/s.Through simulation experiments,the deposition state of wheat grains,the velocity of wheat grains,the pressure drop of the conveying system,and the energy consumption of the system in axial flow conveying and cyclone conveying were compared.It was found that the cyclone conveying was significantly better than the axial flow conveying,in which the grains spiraled forward,and the conveying effect was better.The experimental verification showed that the conveying effect was consistent with the simulation results.Under the same working conditions,the cyclone conveying can effectively inhibit the deposition of grains,distribute grains evenly,reduce the friction with the pipeline effectively and realize longer conveying distance,higher conveying efficiency and good conveying effect.