带捏合块的渐加速型单螺杆三维流场分析

Three-dimensional flow field analysis of a progressively accelerating single screw with kneading blocks

目的:提高单螺杆挤出机的混合性能和工作效率.方法:设计了一种利用行星轮组件和混合元件的同轴渐加速单螺杆,利用Ansys/cfx对其流道进行了三维流场分析,得到了宏观压力场、速度矢量图、速度流线图以及轴向速度变化曲线并与传统单螺杆进行了对比,结果:随着螺杆转速的不断变大,物料在机筒内停留时间变短,渐加速螺杆的挤出效率得以提高20%~25%,使得耗能大大减少,由于捏合块的存在,物料在捏合块处被反复挤压,使得渐加速型单螺杆在增加产能的同时混合性能又可以得到保证.结论:同轴渐加速单螺杆高速旋转的捏合块可使物料混合更充分,且能缩短物料在螺杆中的停留时间,提高产量.

Objective:In order to improve the mixing performance and work speed of a single screw extruder increase.Methods:A coaxial gradual acceleration single screw using planetary wheel assemblies and mixing elements was designed.Using ansys/cfx to conduct the three-dimensional flow field analysis of the flow channel,the macro pressure field,speed vector diagram,speed streaming diagram and axial speed changes,were finished,which was compared to the only traditional pillar.Results:As the speed of the pillar continues to increase,the time for the material to stay in the barrel becomes shorter,and the extrusion efficiency of the gradual acceleration screw can be improved by 20%to 25%,so that the energy consumption is greatly reduced,due to the presence of the kneading block,the material is repeatedly squeezed at the kneading block,so that the gradual acceleration of the single screw in the increase in production capacity at the same time the mixing performance can be guaranteed.Conclusion:The coaxial gradual acceleration of the single screw high-speed rotation of the kneading block can make the material mix more fully,and can shorten the residence time of the material in the screw,improve the output.