摘要
在单螺杆挤出机中,通过螺杆的轴向振动将振动力场引入聚合物固体输送过程,提出振动力场强化固体输送过程的新概念.以螺槽中运动的物料为对象建立了振动力场强化固体输送过程的数学模型,并获得了物料沿螺槽方向输送的压力(密度)、速度的近似解析解.传统固体输送过程就是当螺杆轴向振动的振幅为零时的特例,此时的压力降与DarnellandMol理论一致,但不同的是物料速度及密度沿螺槽方向是变化的,从而修正了DarnellandMol固体输送理论.螺杆的轴向振动提高了固体输送平均压力,缩短了固体输送的长度,增加了固体输送角.透明料筒全程可视化实验挤出机证明了螺杆轴向振动确实缩短了物料固体压实输送所需的螺槽长度.
In the single-screw extruder a vibration force field was applied to the solids conveying process by the axial vibration of the screw and a novel concept of the solids conveying process being strengthened with the vibration force field was brought forward. A mathematical model that described the solids conveying process with the vibration force field was established and the approximate analytical solutions of the pressure and velocity of the solids conveying along the screw channel were obtained. When the amplitude of the axial vibration of the screw was zero, the new solids conveying theory presented in this paper could describe the conventional solids conveying process, namely, the conventional solids conveying process was the special case of the one being strengthened with the vibration force field. In the new theory, if the screw has no axial vibration the solids conveying pressure is the same as that of the Darnell and Mol theory, but the density and velocity of solids conveying along the screw channel are variable, which has modified the Darnell and Mol theory in which the density and velocity of the solids conveying along the screw channel are considered invariable. The theoretical results reveal that the axial vibration of the screw can increase the average pressure of solids conveying, decrease the channel length of the solids conveying section and increase the solids conveying angle. In the self-developed experimental extruder with transparent barrel, the successive visualization experimental results proved that the axial vibration of the screw indeed shortened the channel length needed for solids compressing and conveying.
出处
《化工学报》
EI
CAS
CSCD
北大核心
2006年第11期2568-2576,共9页
CIESC Journal
基金
国家自然科学基金项目(10472034
10590351).~~
关键词
单螺杆挤出机
振动力场
固体输送
single screw extruder
vibration force field
solids conveying zone
