The Multistage Harmonic Choice Wizard is a valuable tool for accurately simulating cyclically symmetric systems with multiharmonic phenomena using the multistage analysis procedure. Multistage displacement solutions are the sum of contributions of many harmonic functions, only some of which significantly affect the response. This wizard helps you determine which harmonic indices (HIs) should be included in each stage for an accurate response, a useful tool as:
Including multiple HIs can improve accuracy for models with multiharmonic phenomenon
Including all harmonics in each stage increases the time and computational effort enough to defeat the purpose of multistage modeling
Randomly choosing harmonic indices may lead to a solver error if the chosen HIs are uncoupled, resulting in no constraint equations generated between stages
The Multistage Harmonic Choice Wizard calculates and lists which harmonic indices (HIs) are relevant at each stage by evaluating the relationship between the nodal diameters and HIs. For an example problem demonstrating this and detailing the underlying equations, see Static Analysis of a 2-Stage Disk with Pinholes. For a discussion on the concepts of harmonic index and nodal diameters of a cyclically symmetric structure and their relationship, see Understanding Harmonic Index and Nodal Diameters in the Cyclic Symmetry Analysis Guide.