复杂摘棉气力输送系统流固耦合数值建模与流场分析

Fluid-solid Coupling Numerical Modeling and Flow Field Analysis of Complex Cotton Picking and Pneumatic Conveying System

针对复杂的摘棉过程进行分析同时对气力输送系统进行数值建模。采用Fluent软件中的滑移网格与UDF来控制采棉装置中各个部分的运动并实现运动过程中的流场分析,通过网格的动态变化来模拟内部的流场变化。结果表明:运动到2.5 s、不同的出口速度时,吸力输棉装置的入口速度对采棉装置内部流场的影响较大,需要合理控制吸力输棉装置速度才能输送籽棉;同时在满足籽棉气力输送条件时出口速度最小为25 m/s时,采棉装置内部的速度和压力云图分布较为均匀;在输棉区域中,气流方向与脱棉刷方向相同的时候速度更大,有利于籽棉的输送。采棉装置数值建模和流场分析方法能够为之后的设计与优化提供参考。

The complicated cotton picking process was analyzed and numerical modeling for the pneumatic conveying system was carried on. The slip grid and UDF in the Fluent software were used to control the movement of each part of the cotton picking device and to realize the flow field analysis during the movement. The internal flow field change was simulated through the dynamic change of the grid. The results indicate that when moving to 2.5 s at different outlet speeds, the inlet speed of the suction cotton conveying device has a greater influence on the flow field inside the cotton picking device, it is necessary to reasonably control the speed of the suction cotton conveying device to convey the seed cotton;while the outlet speed of the seed cotton is at least 25 m/s under the conditions of pneumatic conveying, the speed and pressure cloud diagram inside the cotton picking device are more evenly distributed;the speed is higher when the airflow direction in the cotton conveying area is the same as the direction of the docking brush. The numerical modeling of the cotton picking device and the analysis method of the flow field can provide reference for the subsequent design and optimization.