Modeling method for MJ bolt and nut finite element meshes

Abstract

The invention discloses a modeling method for MJ bolt and nut finite element meshes. The method comprises the following specific steps: I, summarizing geometrical features of a bolt and a nut; II, performing mathematical description on a thread zero-position section of the bolt; III, performing mathematical description on a thread zero-position section of the nut; IV, generating unthreaded region finite element meshes of the bolt and the nut; and V, generating thread node offsets of the bolt and the nut, and performing node movement on meshes on threads in order to obtain a threaded bolt. Through adoption of the modeling method, the MJ bolt and nut finite element meshes with threaded structure features can be generated rapidly and effectively. The meshes are hexahedron co-node meshes, so that errors caused by adoption of a TIE command or a tetrahedron mesh can be effectively avoided, and the calculation accuracy is increased greatly.

Description

technical field [0001] The invention belongs to the field of finite element simulation, and in particular relates to an aerospace vehicle MJ bolt and nut finite element mesh generation method. Background technique [0002] Bolted connections are widely used in the development of aerospace structures. From structural system force and moment transmission; structural sealing; structural installations such as inertial groups and cables, bolt connections are widely used. However, due to the relative tightness of the threaded connection, we cannot directly measure it. We can only indirectly measure the deformation and sliding of the overall structure of the bolt by means of force-measuring washers, extensometers, and ultrasonic waves. Especially bad. [0003] The use of finite element simulation is an important means to study its mechanical properties, but the thread division is difficult, and it takes a lot of time to divide the mesh. At present, most of them use TIE or tetrah...

AI Technical Summary

Problems solved by technology

However, the formula of this method is relatively complicated and requires node merging and elimination; the patent applied by Xi'an Jiaotong University Hong Jun et al., patent application number: 201110302715.9, although the grid contour node method is used, this method can only describe 17 axial points within the pitch A limited number of grids, and for bolts or nuts with large engineering diameters, the number of grids will be small and the calculation accuracy will be poor

And it cannot be extended to practical engineering problems such as left-handed, right-handed and work difference

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