MODTRAK

Bulk Data Entry Defines parameters for mode tracking in optimizations with eigenvalue analysis.

Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
MODTRAK SID LOWRNG HIGHRNG MFILTER     TRAKSET TRAKMETH  

Example

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
MODTRAK 11 3 5 0.6     111 2  

Definitions

Field Contents SI Unit Example
SID Set identification number.

No default (Integer > 0)

  
LOWRNG Lowest mode number in range to search.

Default = 0 (Integer ≥ 0)

  
HIGHRNG Highest mode number in range to search.

Default = number of total modes (Integer ≥ 0)

  
MFILTER Filtering threshold used in mode tracking.

Default = 0.7 (for CORC and MACSR), 0.5 (for MAC) (Real ≥ 0.0)

  
TRAKSET Element SET ID to define a specific part of a model for mode tracking. Enables component-level mode tracking.

Default = blank (Integer > 0)

  
TRAKMETH Criterion employed for mode tracking. 1

Default = 0 when TRAKSET=blank, 1 when TRAKSET is activated (0 = CORC, 1 = MACSR, 2 = MAC)

  

Comments

  1. The criteria available for tracking are:
    • Mass cross-orthogonality check (CORC)
    • Modal assurance criterion (MAC)
    • Modal assurance criterion square root (MACSR)
    Refer to PARAM, TRAKMETH for more information.
  2. CORC criterion is not applicable when TRAKSET is activated.
  3. This MODTRAK Bulk Data Entry should be referenced in a subcase via the MODTRAK Subcase Information Entry. PARAM, TRAKMETH and PARAM, MFILTER are ignored in the subcases that contain a MODTRAK Subcase Information Entry.