During the mesh generation process ABAQUS/CAE uses the seeds that you create as target locations for nodes along the edges of the mesh. However, if you are using quadrilateral- or hexahedral-shaped elements, a close match between your seeds and nodes depends heavily on the following:
The element shapes you allow in transition regions
You will obtain a better match between your seeds and the nodes of the mesh if you allow triangular elements in transition regions. The seeds and the nodes are less likely to match if you restrict your mesh to including only quadrilateral elements.
The mesh transition setting
You will obtain a better match between your seeds and the nodes of the mesh if you allow for mesh transition.
The meshing technique
The mesh generated using the advancing front meshing algorithm matches your seeding better than the mesh generated using the medial axis algorithm.
The seed constraints
Fully constrained seeds closely match the generated nodes in both number and position. However, you must fully constrain only a few edges of a part or part instance; otherwise, ABAQUS/CAE will not be able to generate a mesh.
How neighboring regions are seeded
When meshing multiple regions, ABAQUS/CAE often redistributes the elements so that the mesh is compatible between regions. Even though a single region's seed arrangement may be adequate for generating a mesh on that one region, the seed arrangement may need to be changed since the number of elements must be compatible with neighboring regions along shared edges.
Note: Mesh compatibility between part instances is not guaranteed. In some simple cases seeding can help achieve part-to-part mesh compatibility. Techniques for obtaining compatible meshes are described in “Compatible meshes between part instances,” Section 17.12.3.