发射药螺杆挤压机叶片强度分析及结构参数优化

Strength Analysis and Structural Parameter Optimization of Propellant Screw Extruder Blade

对于发射药挤出成型用的螺杆挤压机的双锥度螺杆,在采用某种工艺的时候,药料的相互剪切和挤压作用大大提高。利用ANSYS有限元分析软件,通过模拟药料在挤压过程中的流动和应力分布情况以及流固耦合,对现有的螺杆进行强度分析,校核其是否适应新的工艺。以降低流道内最大压力差为优化目标,螺杆强度为约束条件,通过改变螺杆的结构参数,提高螺杆挤压机的挤出效率。结果表明:楔形角对流道最大压力差影响显著大于螺棱宽度;通过正交试验得到最佳参数组合为楔形角均为24°,螺棱宽度为1.5 mm,此挤出流道内压力差达到最小。

For the double taper screw of the screw extruder used for propellant extrusion molding,the mutual shear and extrusion action of the charge is greatly improved when a certain process is adopted.Using ANSYS finite element analysis software,by simulating the flow distribution,stress distribution and the fluid-solid coupling of the charge in the extrusion process,the strength analysis of the existing screw was carried out to check whether it is suitable for the new technology.The maximum pressure difference in the flow passage was taken as the optimization objective,and the screw strength was taken as the constraint condition.By changing the structural parameters of the screw,the extrusion efficiency of the screw extruder was improved.The results show that the influence of wedge angle on the maximum pressure difference of the flow passage is more than screw width.By the orthogonal test,the best parameter combination is the wedge angle are both 24°and the width of the screw is 1.5 mm,the pressure difference in the extrusion passage reaches the minimum under this parameter combination.