MODCONT

MODCONT, MLSkey, EnforcedKey, --, FastLV
Specify additional modal analysis options.

SOLUTION: Dynamic Options

MLSkey

Multiple load step key:

OFF	—	Perform the modal analysis (compute the eigenvalues and the load vector) for each load step. (default)
ON	—	Perform the modal analysis (compute the eigenvalues and the load vector) only for the first load step; form the load vector for each subsequent load step (without repeating the eigenvalue calculations) and write all load vectors to the Jobname.mode file for downstream mode-superposition analyses.

EnforcedKey

Enforced motion key:

OFF	—	Do not calculate enforced motion vectors. (default)
ON	—	Calculate enforced motion vectors and write them to the Jobname.mode file.

--

Unused field

FastLV

Fast load vector generation key; valid only when MLSkey = ON:

OFF	—	Do not activate fast load vector generation (default).
ON	—	Activate fast load vector generation. This option is only supported when each load vector is based on a unique element surface load (SFE) applied on one element, and the element result superposition key is activated (`MSUPkey` = YES on MXPAND).
NOEXP	—	Activate fast load vector generation without modal expansion (MXPAND, -1). This option activates node-based mode file scoping. Mechanical APDL postprocessing of modal and downstream nodal and element results is prohibited with this method.

Notes

Specifies additional modal analysis (ANTYPE,MODAL) options.

Use the LVSCALE command to apply the desired load in a mode-superposition transient or harmonic analysis.

When MSUPkey = YES on the MXPAND command, the maximum number of load vectors allowed in the Jobname.mode file defaults to 1000. To increase this limit, use the command /CONFIG,NUMLV. When FastLV = ON, the limit is automatically set to 1x10⁶and cannot be changed.

The maximum number of load vectors that can be used in the downstream mode-superposition transient or harmonic analysis is the number of load vectors written in the Jobname.mode file.

Generation of multiple loads (MLSkey = ON) is supported by the Block Lanczos, PCG Lanczos, Supernode, Subspace, Unsymmetric, and QRDAMP mode extraction methods.

The enforced motion calculation (EnforcedKey = ON) is supported by the Block Lanczos, PCG Lanczos, Supernode, Subspace, and QRDAMP mode extraction methods.

Menu Paths

This command cannot be accessed from a menu.