多层套扁挤压筒的热-力耦合有限元分析及结构优化

基于ANSYS软件,采用间接法对多层套扁挤压筒进行了热-力耦合数值模拟,分析了扁挤压筒在内压、预紧力及热载荷作用下的温度场和应力场;通过正交实验法,分析了工作内压、过盈量、衬套数、内孔尺寸、整体尺寸及材料对扁筒中热应力的影响。结果表明:各层套的温度分布不均匀,呈现出由外衬套向内衬套增大的趋势,且外层的温度分布比内层与中层均匀;热应力的存在使扁筒的等效应力更均匀;增大工作内压和过盈量会使扁筒的等效应力和接触应力均增大;选取三层套、合适的内孔和中衬的尺寸以及经济合理的模具材料更有利于提高筒的装配效果和降低其等效应力。模拟分析获得了较为合理的工艺参数,为优化扁筒的结构设计和装配提供了参考依据。

Thermal stress coupling finite element analysis and structural optimization of multi-layer flat extrusion container

The coupled thermal-mechanical numerical simulation was carried out by the indirect method for the multi-layer flat extrusion container based on ANSYS software,and the temperature and stress distribution were analyzed under different extrusion conditions of internal pressure,preloaded stress and thermal load.Then,the influences of inner working pressure,magnitude of interference,numbers of bushing,inner hole size,overall size and tool material on the thermal stress distribution of flat container were analyzed by the orthogonal experiment method.The results show that the inhomogeneous distribution of temperature has an increasing tendency from the outer bushing to the inner bushing,and the outer temperature is more uniform than that of inner and intermediate.Furthermore,the equivalent stress distribution of the flat extrusion container is more uniform due to the existing thermal stress,and the equivalent stress and contact stress of the container increase with the increases of inner pressure and magnitude of interference.Thus,the applications of three-layer,appropriate sizes of inner hole and intermediate bushing,and economical rationally die material are of great advantages to enhance the assembly effect and to reduce the equivalent stress.At last,the reasonable process parameters are obtained,which provides the reference for optimizing the structure design and assembling the flat extrusion container.