自动振打除灰装置传递接触模型有限元分析

Finite Element Analysis of Transitive Contact Model for Auto-rapping Ash Removing Devices

自动振打除灰装置传递杆杆身与凸台连接处经常在冲击过程中破坏失效,导致振打器无法继续工作。为解决这一问题,需要对振打器的整个传递接触模型进行研究和优化。运用软件Ansys/ls-dy-na建立了机械振打器的有限元模型,并分别对现有和改进后传递接触模型下的整个冲击过程进行有限元分析。对比不同情况下传递杆上的最大应力,发现连接处损坏的原因是撞击杆具有轴向夹角,通过调整连接处以及改变传递模型接触面形状可以有效改进现有的传递接触模型。当连接处倒圆角半径增大到22mm并且传递模型接触面是半径为400mm的球面时,传递杆可以有效避免出现过大应力集中,从而将振打器的寿命延长到设计范围。

The impact damage on the joint between convex platform and transitive rod＇ s body can disable rapping device, the study on transitive contact model of the rapping device and optimizing it become necessary. The Ansys/ls-dyna was used to build finite element model of rapping device so that the impact on both existing and modified transitive contact models can be analyzed respectively. Comparing the maximum stress on the transitive rod under different conditions shows that the stricken rod with an axial angle is the cause of the joint damage ; adjusting the joint and changing the shape of transitive contact surface can improve current transitive contact model ; increasing the fillet radius at the joint to 0. 022m and changing the transitive contact surface in- to a sphere with 0.4m radius, the stress concentration there can be avoided so as to have service life of rapping device extended to the design range.