5MN扁挤压筒热力耦合及疲劳寿命分析

Analysis on Thermal-Mechanical Coupling and Fatigue Life for 5MN Flat Extrusion Container

以5MN扁挤压筒为研究对象,采用ANSYS APDL进行热力耦合分析,运用ANSYS nCode Design Life进行疲劳寿命分析,考察工作压力与热应力共同作用下的等效应力分布,以及热应力对疲劳寿命的影响。研究发现:1)工作压力与热应力之间存在叠加抵消效应,在二者共同作用下,扁挤压筒的等效应力峰值回落约1.2%;2)当热应力与工作压力共同参与疲劳寿命计算时,扁挤压筒的最低疲劳寿命由不考虑热应力时的3182次提高至10710次,与实际使用寿命更加吻合。结果表明,在扁挤压筒物理性能研究中,热力学与结构力学的共同作用不是二者的简单叠加,耦合作用不容忽视。

Taking 5MN flat extrusion cylinder as the research object,ANSYS APDL is used for the thermal-mechanical coupling analysis,and ANSYS nCode Design Life is used for the fatigue life analysis.The equivalent stress distribution under the joint action of working pressure and thermal stress,as well as the influence of thermal stress on the fatigue life,are investigated.The results show that:1)there is a superposition counteraction effect between the working pressure and the thermal stress,and the peak value of the equivalent stress of the flat extrusion cylinder drops by about 1.2%under the combined action of the two;2)when the thermal stress and the working pressure jointly participate in the fatigue life calculation,the minimum fatigue life of the flat extrusion cylinder increases from 3182 times without considering the thermal stress to 10710 times,which is more consistent with the actual service life.The results show that the interaction of thermodynamics and structural mechanics is not a simple superposition of the two;their coupling effect cannot be ignored.