About Complex Frequency Steps

A complex frequency procedure performs eigenvalue extraction to calculate the complex eigenvalues and the corresponding complex mode shapes of a system.

See Also
Defining Complex Frequency Steps
In Other Guides
Complex Eigenvalue Extraction

Complex frequency steps use the Lanczos eigensolver, and you must define a preceding frequency step so that eigenfrequencies are extracted prior to the complex eigenvalue extraction.

Complex frequency steps also include several advanced options not available in frequency steps. These options include:

  • Friction-based damping effects
  • Evaluation of frequency-dependent material properties for a specified frequency
  • Cutoff frequency for unstable, complex modes
  • Control of matrix storage