Verification Based on Modal Assurance Criterion for OptiStruct

This gives information on the model correlation across two results. The mode pairs with MAC numbers are extracted.

Modal Assurance Criterion (MAC) measures the correlation between two vibrating shapes.

Currently, the assumed node tolerance is 10.0 and the MAC threshold is 0.6.

Complete details of the model correlation with MAC numbers and the correlation plot are published.

Mode number, frequency, percent frequency difference, and MAC values are listed in the table.

Starting frequency and end frequency, along with the number of MAC values to be calculated, are taken as input.

Along with the OptiStruct solver results comparison, the MAC data is key to identifying any problems in the model.

Use cases covered are for:

• Results from two models that may be from different design iterations, parametric study.
• Results from the same model run across two HyperWorks versions.

Figure 1.