modal analysis of blade with pre-stress

mattone

Hi All,

I would like to know if it is possible to perform a modal analysis of a turbine blade affected by centrifugal force to evaluate its natural frequencies at different speeds.

Generally, running the modal analysis loads are not considered.

Thanks
Mario

[Deleted User]

Yes it is possible. Mecway has stress stiffening and spin softening effects included as of version 3. I compared results to ANSYS 15 and 16 and had good agreement. Mecway does not have coriolis/gyroscopic effects though. So, if the rotor is on a flexible shaft, the results won't be accurate. However, Victor has recently added compatibility with Calculix. Calculix has stress stiffening, spin softening, and coriolis/gyroscopic effects.

mattone

Thanks Prop_design