苜蓿干燥与茎叶分离设备设计与CFD模拟

摘要

设计了滚筒式苜蓿干燥与茎叶分离设备,可在完成干燥的同时实现茎叶分离加工.采用预干燥滚筒与三回程干燥滚筒的组合结构,可实现苜蓿茎、叶的均衡干燥.利用CFD方法对设备内部的空气流场进行了仿真模拟,可以看出流场的风速分布反映了设备的结构特点,且不存在明显的涡流现象,能够满足输运物料、均衡干燥和茎叶分离的要求.风门开启面积对分离室内的风速影响显著,并且呈现出一定的规律.根据模拟结果可得,满足茎叶分离风速条件的风门最佳开启面积为(150×150)～(200×150)mm2.%For the sake of achieving uniform drying and separation of alfalfa leaves and stems in one process, a quad-pass rotary drum dryer-separator was designed, which mainly comprised the pre-drying, quick-drying, tempering and separating zones. The air flow in the dryer-separator was simulated by using CFD method with applying the standard k - e model, and the effect of different opening areas of the adjusting gate on the velocity in the separating chamber was analyzed emphatically. It was found that the desired velocity for leaf-stem separation in the separating chamber was gained, when the opening area of the adjusting gate was (150 x 150) ~ (200 X 150) mm2.