摘要
[目的]探讨物料在机筒内壁面和螺杆表面发生的滑移现象及对同向双螺杆挤出过程的影响。[方法]利用相对运动法设计三维模型,设定不同的滑移边界条件并进行有限元模拟,通过仿真分析得到相关物理场数据,并计算其体积流率。[结果]与无滑移时相比,螺杆滑移条件下流道内压力减小,剪切速率减小,黏度增加;壁面滑移条件下,在螺杆与机筒间隙处压力减小,剪切速率减小,黏度增加,在螺杆啮合处则相反,即压力增加,剪切速率增加,黏度减小。螺杆滑移条件下的产量提升了28%,壁面滑移条件下的产量下降了62.5%。[结论]壁面滑移现象的发生有助于提升螺杆在螺杆啮合处的剪切能力,而螺杆滑移现象的发生则有利于提高同向双螺杆的挤出产量。
[Objective]To investigate the influence of material slip on the inner wall of the barrel and the surface of the screw on the extrusion process of the co-rotating twin screw.[Methods]The 3D model is designed by the relative motion method,and different slip boundary conditions are set and simulated by the finite element method.The relevant physical field data are obtained by simulation analysis,and the volume flow rate is calculated.The physical field of the extrusion process is studied.[Results]Compared with the non-slip condition,the pressure in the flow channel decreases,the shear rate decreases,and the viscosity increases under the screw slip condition.Under the condition of wall slip,the pressure decreases,the shear rate decreases,and the viscosity increases at the gap between the screw and the barrel.On the contrary,the pressure increases,the shear rate increases,and the viscosity decreases at the screw engagement.The analysis of the volume flow rate in the extrusion process showed that the yield increased by 28%under the screw slip condition,and the yield decreased by 62.5%under the wall slip condition.[Conclusion]The occurrence of the wall slip phenomenon helps to improve the shear ability of the screw at the screw engagement,and the occurrence of the screw slip phenomenon is beneficial to improve the extrusion yield of the co-directed twin screw.
作者
徐珍
刘子豪
黄志刚
XU Zhen;LIU Zihao;HUANG Zhigang(School of Computer and Artificial Intelligence,Being Technology and Business University,Beijing 100048,China;Plastic Beijing Municipal Key Laboratory of Health and Safety Quality Evaluation Technology,Beijing 100048,China)
出处
《食品与机械》
CSCD
北大核心
2024年第9期99-105,144,共8页
Food and Machinery
基金
国家自然科学基金面上项目(编号:32172277)。
关键词
螺杆挤出机
同向啮合
滑移现象
有限元分析
screw extruder
simultaneous meshing
slip phenomenon
finite element analysis
