This MIDAS NFX STR tutorial demonstrates how to perform modal analysis of a monitor assembly and interpret its natural frequencies, mode shapes, and mass participation ratios. Follow the structural FEA workflow to understand how the assembly vibrates and prepare its modal results for frequency response analysis.

Modal Analysis Workflow:

• Model and Contact Definition
Assign material properties and define the contact and boundary conditions of the monitor assembly to represent its connections and supports.

• Concentrated Mass Application
Apply a 1 kg concentrated mass to account for the weight omitted from the simplified model and better represent the actual assembly’s vibration behavior.

• Natural Frequencies and Mode Shapes
Run the modal analysis to calculate the assembly’s natural frequencies. Review each mode animation to see how the structure deforms and vibrates at different frequencies.

• Mass Participation and Result Review
Examine the eigenvalue results and mass participation ratios to identify the significant vibration modes and check whether sufficient modes have been included for subsequent dynamic analysis.

Modal analysis helps engineers understand a structure’s fundamental vibration characteristics. Since resonance can occur when an external excitation frequency matches a natural frequency, these results provide a foundation for further studies, including frequency response analysis.