Modal Displacement results

The Modal Displacement results are the default result for a modal frequency analysis, and demonstrate the deformed shape of the vibrating structure. These results are displayed as a color contour plot.

Important: The absolute magnitudes of the modal displacements are not indicators of how much the structure actually deflects when vibrating.

The modal displacements are not scaled to any specific excitation (such as a harmonic force from an out-of-balance motor). They are normalized, which means that the maximum displacement is always one length unit, and the minimum displacement is always zero. The range is fixed from zero to one length unit for every model and every vibration mode.

Note: In the online results viewer, normalized modal displacement plots show no units on the legend. You cannot change displacement units for Modal Frequencies studies.

When the model is fully unconstrained you can expect 6 rigid body vibration modes:

X, Y, and Z translation
X, Y, and Z rotation

Displacement Options

Select a displacement result from the Browser. You can view the total normalized displacement or each component:

Total Modal Displacement: Displays the magnitude of the normalized displacement, regardless of its direction. This value is always positive. The magnitude is the total normalized distance any given point has moved.
Modal Displacement X: Displays the X component of the total normalized displacement.
Modal Displacement Y: Displays the Y component of the total normalized displacement.
Modal Displacement Z: Displays the Z component of the total normalized displacement.

Use the Mode dropdown above the legend to switch between vibration modes.

The following equation describes the relationship between the total normalized displacement magnitude (δ) and its components (δx, δy, and δz):

δ = ( δx2 + δy2 + δz2 )1/2