# RSPEED

Bulk Data Entry Specifies a set of reference rotor speed values for asynchronous analysis in Rotor Dynamics.

## Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
RSPEED SID S1 DS NDS
MDTRAK CORU     PRTCOR

## Example

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
RSPEED 25 1500 50 5

## Definitions

Field Contents SI Unit Example
SID Set identification number.

No default <Integer > 0>

S1 Specifies the first reference rotor speed in the set.

No default <Real > 0.0>

DS Specifies the increment in reference rotor speed. This value is added to each successive entry starting from the first entry (S1).

No default <Real > 0.0>

NDS Number of reference rotor speed increments.

Default = 1 <Integer > 0>

MDTRAK Identifies the Mode-tracking option. 4 5
MAC
Modal Assurance Criteria.
MMAC
MAC in modal space.
NC20
Normalized Cross Complex Orthogonality.
SLCON
Slope Continuity Approach.
blank
Mode-tracking is not activated.

CORU Upper Correlation Limit.

Default = 0.7 <Real > 0.0>

PRTCOR
0 (Default)
Correlation matrix is not printed.
1
Prints correlation matrix between current and previous speeds.

1. The RSPEED Bulk Data Entry is referenced by the SPEED field on the RGYRO Bulk Data Entry. If an integer value is specified in the SPEED field, multiple reference rotor speeds specified in the RSPEED entry are used in asynchronous analysis.
2. In asynchronous frequency response analysis or static analysis, if the RSPEED Bulk Data Entry is referenced in RGYRO, only the first frequency is considered. In complex eigenvalue analysis, the full range specified by RSPEED is considered.
3. The following formula is used to populate the set of reference rotor speeds:(1)
Where,
${R}_{1}$ , ${R}_{2}$ , … ${R}_{NDS}$
Represents the set of reference rotor speeds
$S1$
First reference rotor speed
$DS$
Reference rotor speed increment
$NDS$
Number of reference rotor speed increments
4. There is no single mode tracking method with universal applicability across the entire spectrum of industrial rotor dynamics models. Different Mode-Tracking options can be used, depending on the problem definition and the user’s requirements. As a general guideline, the following order of mode tracking options is recommended: NC20, MMAC, MAC, and SLCON.
5. For the NC20, MMAC and MAC mode tracking methods, you can fine-tune the mode tracking result by requesting the output of the correlation matrix and changing the value of the upper correlation limit.