| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a system capable of finding easily the optimum shape of a blank, and capable of simplifying analytical work, in a hydroforming simulation system using a finite element method. <P>SOLUTION: An analytical model of an xyz orthogonal coordinate system is prepared, an X-axis is set to be extended longitudinally along the center part of the analytical model, xyz coordinates of each element are transformed into an Xθr polar coordinate system using as respective components a distance X from the origin on the X-axis, a rotation angleθaround the X-axis from a plane including the X-axis and a vertical-directional distance r from the X-axis, the analytical model is developed using values of Xθr coordinates in the each element as values in an orthogonal Xθr coordinate system, the each element is rotated around the center to be brought into parallel to an Xθplane, the each element is projected on the Xθplane, the each element is deformed while keeping balance of a stress to conform nodal points sharing the same nodal point in the analytical model and to bring both end parts along an X-axis direction into the same deformation, a plane-developed model is prepared thereby, and the each element of the model is inverse-transformed into the Xθr polar coordinate system to generate a tube material shape. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
