摘要：二级除杂是玉米小区育种的重要过程，小区收获机除杂效率影响着玉米品种的纯净度。为了提高玉米小区收获机的除杂作业效率，解决除杂装置整机空间占比大的问题，本文结合康达效应和伯努利原理，设计了一种翼型曲面除杂装置。通过Fluent软件进行单流场分析，研究了除杂装置的速度分布规律和压力分布规律，得到了半径为42.5mm、105mm、和175mm的圆盘在不同雷诺数下的气流偏转角，优化了初始模型。通过CFD-DEM气固耦合仿真实验，建立了玉米种子力学模型，得到了不同入口风速下玉米籽粒速度的置信区间，设置单因素实验探究不同直径的颗粒混合物的分离效果。通过台架试验验证该装置对玉米脱出混合物中轻质杂质分离功能的可行性，试验结果表明籽粒含杂率低至1.01%，其性能指标满足设计要求。该研究成果对于玉米小区收获机的除杂装置设计提供了新的参考方案。

Abstract：Secondary removal is an important process in corn plot breeding. Efficiency of debris removal device in plot harvesters affects the purity of corn varieties. This study designed a device with a wing-shaped curved surface to separate impurities based on the Coanda effect. This device improves the efficiency of the corn plot harvester's debris removal operation. Its small size reduces the amount of space it takes up in a corn plot harvester. The article analyzed the device flow field by ANSYS Fluent and investigated the velocity distribution law and pressure distribution law. The computations have obtained the airflow deflection angles for discs with radii of 42.5 mm, 105 mm, and 175 mm at different Reynolds numbers to optimize the initial model by CFD-DEM gas-solid coupling simulation experiments. Besides, the experiment explored the separation effect of different diameters of grain mixtures by a one-factor control method, and article draws conclusions concerning confidence intervals for corn kernel velocities at different inlet wind speeds. The bench test data indicated that the impurity content of corn kernels was as low as 1.01%, and the operational performance index of this device met the expected design requirements. The research results provide a new reference program for the design of the debris removal device of corn plot harvester.
 

小区收获机；康达效应；CFD-DEM；除杂装置