Any structure has a potentially unlimited number of natural frequencies—also known as "modes." Before performing a
DesignSight frequency simulation, you must specify some limits to determine the range of frequencies that are calculated.
A frequency range can be specified in two ways:
- Number of modes
- Specify the number of modes that should be calculated. DesignSight determines the lowest natural frequency of the model, followed by sequentially larger frequencies up to the specified number of modes.
- Frequency range
- Specify a maximum and minimum value for the calculated frequencies. DesignSight determines only frequencies that fall within this range.
If you specify both a Number of modes and a Frequency range, DesignSight calculates the lowest natural frequency within the given range. Sequentially higher frequencies are calculated until either upper limit is reached: the total number of calculated modes or the top of the frequency range.