削边形式对筒体与封头过渡区应力分布的影响

Effect of Different Edge-cutting Shapes on Stress Distribution in Transition Zone between Cylinder and Its Head

利用ANSYS 16.0有限元分析软件,以半球形封头、椭圆形封头和无折边球形封头3种凸形封头为研究对象,通过改变削边长度和削边形式,得到其应力分布规律,并进行优化分析。结果表明:3种封头形式压力容器最大等效应力均集中于筒体和封头过渡区域;在相同尺寸和相同削边形式下,应力集中系数大小顺序为无折边球形封头>椭圆形封头>半球形封头;随着削边长度L的增加,椭圆形封头和无折边球形封头压力容器应力集中系数K均呈增大的趋势,对于半球形封头压力容器,削边长度L出现临界值;半球形封头压力容器优化效果最为明显。

Through making use of ANSYS 16.0 software,the three convex heads like spherical head,elliptical head and non-folded spherical head were taken as the object of study. Through changing the length and shape of edge-cutting,the stress distribution law was analyzed and optimized to show that,the maximum equivalent stress of pressure vessels with three kinds of head forms is concentrated in transition zone between the cylinder and its head. As for the same size and the same trimming form,the order of stress concentration factor can be a non-folded spherical head,elliptical head and hemispherical head in turn;with the increase of trimming length L,the elliptical head and non-folded head,the stress concentration factor K of spherical head pressure vessel increases;for spherical head pressure vessel,the critical value of trimming length L appears and the optimization effect of hemispherical head pressure vessel is the most obvious.