Whirl Speed

Requests the whirl speed calculation option, defines the number of modes, and specifies the spin speed range (if required by the analysis reference frame).

Whirl frame analysis



Num. whirl speed in the GUI specifies the number of modes required to be calculated (code 94.). The whirl ratio is defined for use of whirl speed calculations (code 93.).

Following is the screen dump from the roda input file on this card. In this example the data requests the calculations of the first two modes.



Fixed frame analysis



For the fixed frame analysis, the starting value, final value and an increment of spin speed, either positive or negative, used to calculate the whirl speeds.

Following is the screen dump from the roda input file on this card. In this example the data requests the calculations of the first two modes, for a spin speed range starting at 100.0 rpm and ending at 500 rpm with 20 rpm.



Out of these two analysis frame whichever frame is last selected will be written out inside the roda input file. Cards for both frames will not be written out in the roda input file.