Learning Forum

[leo liu]

1. I used a single sector to calculate the modal of the whole bladed disk under each pitch diameter by cyclic symmetry. I extracted the mass and stiffness matrix of the model after applying cyclic symmetry. The frequency obtained is completely different from the natural frequency without applying cyclic symmetry, and is roughly the same as the frequency calculated by APDL. However, due to the frequency of each pitch is basically the same, I can not be clear which pitch is the extracted mass and stiffness matrix.
2. I want to extract the modeshape data under all pitch diameters. I calculated the first 8 modes under each pitch diameter, and calculated a total of 6 pitch diameters. But I can only extract 423 * 16 matrix. ( 423 is the model degree of freedom ) I don 't know how to get all the modeshapes

[leo liu]

1. I used a single sector to calculate the modal of the whole bladed disk under each node diameter by cyclic symmetry. I extracted the mass and stiffness matrix of the model after applying cyclic symmetry. The frequency obtained is completely different from the natural frequency without applying cyclic symmetry. However, due to the frequency of each node diameter is basically the same, I can not be clear which node diamete is the extracted mass and stiffness matrix.
2. I want to extract the modeshape data under all node diametes. I calculated the first 8 modes under each pitch diameter, and calculated a total of 6 node diametes. But I can only extract 423 * 16 matrix. ( 423 is the model degree of freedom ) I don 't know how to get all the modeshapes