Abstract: In order to avoid the appearence when the already being dried rapeseed could not be separated in time during the operation of rapeseed spin dryer, this paper simulated the air flow field of main working part of rapeseed spin dryer-drying cylinder with the software Ansys Fluent, and explored the effect of airflow inlet type, velocity of inlet airflow and inlet sectional area etc. factors of the drying cylinder on rotational strength of airflow field, velocity component and pressure drop etc. indexes. The paper also estimated, simulated and analyzed the characteristics of outlet airflow field of drying cylinder for effective separation of rapeseed; used a pitot tube to measure the airflow field velocity at the outlet of drying cylinder to verify the correctness of the simulation method. The results showed that the spiral airflow inlet was better than the tangential one in carrying capacity and material separation performance. When the inlet sectional area was constant, the larger the velocity was, the more favorable the airflow field distribution in the drying cylinder was for material separation. The inlet sectional area of the drying cylinder was positively correlated with pressure drop, and had effect on airflow velocity at the outlet section. The airflow field at the outlet was simulated and verified by experiments, and the change trend of airflow field was consistent. The average error between the simulated value and measured value of the airflow velocity at the same point was 6.58%, which verified the correctness of establishing airflow field simulation model of the drying cylinder in this study.

Key words: rapeseed, drying cylinder of spin dryer, numerical simulation, Fluent

摘要： 为了避免油菜旋风式烘干机作业时已达到烘干效果的油菜籽不能及时分离，导致油菜籽过度干燥，借助Ansys Fluent软件对油菜旋风式烘干机主要工作部件干燥筒的气力流场进行仿真分析，探究干燥筒的气流入口型式、入口气流速度及入口截面积大小等因素对干燥筒内油菜籽的分离性能的气力流场旋转强度、速度分量和压降等指标的影响规律。进一步预估并仿真分析油菜籽有效分离的干燥筒出口气流场特性，利用毕托管对干燥筒出口气流场风速进行测量，验证了该仿真模拟方法的正确性。结果表明：干燥筒气流入口型式采用蜗壳式所形成的气流场承载和分离物料能力优于切向式；当入口截面积一定时，速度越大，干燥筒内气流场分布更有利于物料分离；干燥筒入口截面积与压降呈正相关，并对出口段的气流速度有影响。对出口流场进行模拟和实测验证试验，其流场变化趋势基本一致，同一点位的流速模拟值与实测值的平均误差为6.58%，验证了所建立的干燥筒气力流场仿真模型的正确性。

关键词: 油菜籽, 旋风式干燥筒, 数值模拟, Fluent