文档介绍：华中科技大学
硕士学位论文
细粉加料装置料腔内气固两相流场的数值模拟分析
姓名:蔡芬
申请学位级别:硕士
专业:机械电子工程
指导教师:熊烽
2011-01-19
华中科技大学硕士学位论文
摘要
在过滤嘴嘴棒中加入高效吸附剂已经被广泛用于香烟的降焦减害技术中,嘴棒的主
要成分是纤维丝束,所添加的吸附剂一般为细粉颗粒。丝束布料的整个过程由加料装置
来实现。文中分析的加料装置工作时,颗粒从料斗中掉落到料腔中,由于颗粒极小、运
动速度很低,在掉落过程中,丝束相对高速的运动会产生气流扰动,导致加料过程出现
布料不均匀、颗粒随空气排出料腔等问题,影响加料质量,造成物料损失严重等问题。
上述问题产生的根本原因是细微颗粒随扰动的气流运动,颗粒的运动过程实际上是
一种复杂的湍流两相运动,涉及到空气与颗粒相互作用,单纯用实验的方法研究装置性
能,成本高、周期长,文中运用的数值模拟方法克服了这些缺点。
本文采用 FLUENT 软件对细粉加料装置料腔内气固两相流场进行了数值模拟。在
研究了气固两相的数值模拟方法的基础上,简化并建立模型,对加料腔内气相流场进行
了模拟,并考察了结构参数、操作条件对气相流场的影响;在气相流场的基础上,引入
颗粒相,计算出颗粒运动轨迹,模拟颗粒在丝束上布料控制情况。
气相流场的数值模拟结果清楚展现了料腔内气相流场的分布,并且表明了挡板角度
和丝束速度对气相流场的影响规律;气固两相流场的数值模拟结果显示了颗粒相的运动
轨迹,本文在分析该轨迹的基础上给出了大小颗粒的定义,并分别研究了具有不同颗粒
特性和入射方式的大小颗粒在装置内的运动情况,研究结果表明,颗粒较大时,装置性
能好;颗粒较小时,装置性能很差,并针对此情况,提出了一种优化装置的方案。

关键词:细粉加料装置气固两相流数值模拟

I
华中科技大学硕士学位论文
Abstract
Adding high performance adsorbent to filter tips is a widely used technology to reduce
the tar and ponents of cigrette smoke. Fiber tow is the ponent of filter
tips, and the adsorbent added is fine powers in general. The distribution of the powders is
realized by the feeding equipment. In this paper, such an equipment was analysed. When it
works, powders fall onto the fiber tow from the hopper. As the powders are very tiny and its
falling speed is very low, the moving speed of the fiber tow is relatively high, so flow
disturbance will be produced leading to the problems such uneven distribution, powders
flying out of the feeding chamber with the air. As a result, the feeding quality couldn't be
guaranteed. And the waste of powders will be serious too.
The basic reason for the problems above is that the fine powders will move with the
disturbance air flow. In fact, the motion process of the powders is plicated gas-solid
phase motion, including the reaction between the air and the powders. So it would costs more
to study the performance of the feeding equipment in experiment only. And the research cycle
would be longer too