基于FLUENT的饲料环模内孔流场分析

Analysis on the inner flow field of the feed ring mold hole based on FLUENT

环模是饲料加工产业中广泛采用的环模制粒机的核心部件,其中物料在环模孔中的流动状况对饲料制粒成型质量具有重要的影响。本文以加工苜蓿草颗粒为例,利用FLUENT软件分别对两种不同类型的环模内孔进行流场分析,讨论物料经环模压辊作用进入环模孔后模孔内的压力分布及速度变化情况。结果表明:内扩式孔形在入口处压力比直孔小,直孔在入口处应力集中的现象明显;内扩式孔形物料出口速度比直孔大;直孔在临近出口处有应力松弛的现象,而内扩式孔形相当于两次成型,成型质量好。在加工牧草粉体类物料时,环模内扩式孔形优于直孔。此研究为优化环模孔的结构设计提供一定理论参考。

Ring mold is the key part of the granule machine with ring modules.The structural parameters of ring mold hole have an important impact on the quality of the molding material granulation.Two types of flow field in ring mold were respectively analyzed by using FLUENT software with the processing of alfalfa grass particles as the example.The pressure distribution and velocity changes after the material entering the ring mold die by rollers were discussed.The results showed that expanding hole beard smaller pressure than the straight hole at the entrance and stress concentration phenomenon was obvious in straight hole.In addition,the exit velocity of material in expanding hole was larger than the straight one.Stress relaxation phenomenon appeared near the exit of straight hole,the expanding hole has better quality because of the double molding.Expanding hole was better than the straight hole when processing herbage powder materials.A certain theoretical reference of ring mold die structure optimization was provided.