Following are the topics related to the cyclic symmetry modeling for this problem:
The sector model of a centrifugal impeller blade is meshed with SOLID187 elements, as shown in this figure:
The SOLID187 element default settings are used.
SURF154 elements are created on the surface of the impeller blade to apply a pressure load.
The following model shows the low- and high-edge components of the cyclic-sector model:
A tetrahedral mesh is used to obtain the matched node pattern along the high and low edges. To ensure the most accurate solution, it is best to have identical node and element face patterns on the low and high edges of the cyclic sector.
If you issue the CYCLIC command before meshing the cyclic sector (AMESH or VMESH ), the mesh will have identical node and element face patterns on the low and high edges when possible.
For more information about sector low and high edges, see Edge Component Pairs in the Cyclic Symmetry Analysis Guide.
Bonded surface-to-surface contact pairs are used to define contact between the shroud and impeller blade assembly, as shown in this figure:
The pure penalty contact algorithm is used for bonded contact. Because MPC-based bonded contact can create overconstraint along the edge of the cyclic sectors (due to the internally generated constraint equations), the pure penalty or augmented Lagrangian penalty methods are preferred for bonded contact when used in conjunction with cyclic symmetry application.
The contact surface is meshed using CONTA174 elements. The target surface is meshed using TARGE170 elements.