cycexpand

Mapdl.cycexpand(wn='', option='', value1='', value2='')

Graphically expands displacements, stresses and strains of a cyclically symmetric model.

APDL Command: /CYCEXPAND

Parameters:

wn

The window number to which the expansion applies. Valid values are 1 through 5. The default value is 1. The window number applies only to the AMOUNT argument.

option

One of the following options:

ON

Activates cyclic expansion using the previous settings (if any). If no previous settings exist, this option activates the default settings. This option is default.

DEFAULT

Resets cyclic expansion to the default settings.

OFF

Deactivates cyclic expansion.

STATUS

Lists the current cyclic expansion settings.

AMOUNT

The number of repetitions or the total angle.

Value1

NREPEAT

Value2

The number of repetitions. The default is the total number of sectors in 360 degrees.

or

Value1

ANGLE

Value2

The total angle in degrees. The default is 360.

WHAT

A specified portion or subset of the model to expand:

Value1

The component name of the elements to expand. The default is all selected components.

EDGE

Sector edge display key. Possible Value1 settings are:

-1

Suppresses display of edges between sectors even if the cyclic count varies between active windows. This setting is not valid for cyclic mode-superposition (MSUP) harmonic analyses.

Warning

Plots with fewer than the maximum number of repetitions may have missing element faces at the sector boundaries.

0 or OFF

Averages stresses or strains across sector boundaries. This value is the default (although the default reverts to 1 or ON if the cyclic count varies between active windows).

1 or ON

No averaging of stresses or strains occurs, and sector boundaries are shown on the plot. This setting is not valid for cyclic MSUP harmonic analyses.

PHASEANG

Possible Value1 settings are:

n

The phase angle shift in degrees. The valid range for n is 0 through 360. The default is 0. For a modal solution, this value is typically the phase angle obtained via the CYCPHASE command. The expanded modal results are printed or displayed for the specified phase angle shift.

AMPLITUDE (or n ≥ 360)

The amplitude is reported, except for the following circumstances where the amplitude solution is not valid:

• non-component results (such as equivalent stress)

• modal analyses (no amplitude is calculated, and the expanded modal results are printed or displayed at a phase angle of 360º).

SWEEP

For a mode-superposition harmonic solution, the maximum values across a phase angle sweep are reported.

Notes

In preprocessing, the /CYCEXPAND command verifies a cyclically symmetric model by graphically expanding it partially or through the full 360 degrees.

For the postprocessing plot nodal solution (PLNSOL) operation, the command graphically expands displacements, stresses and strains of a cyclically symmetric model partially or though the full 360 degrees by combining the real (original nodes and elements) and imaginary (duplicate nodes and elements) parts of the solution.

For the print nodal solution (PRNSOL) operation, the command expands the printed output of displacements or stresses on a sector-by-sector basis. To learn more about specific PRNSOL behaviors in cyclic analyses, see Using the /CYCEXPAND Command in the Cyclic Symmetry Analysis Guide.

Use of the /CYCEXPAND command does not change the database. The command does not modify the geometry, nodal displacements or element stresses.

The command affects element and result plots only. It has no effect on operations other than plot element solution (PLESOL), plot nodal solution (PLNSOL), print nodal solution (PRNSOL), and calculate harmonic solution (CYCCALC). Operations other than PLESOL, PLNSOL, PRNSOL, or CYCCALC work on the unprocessed real and imaginary parts of a cyclic symmetry solution

If you issue a /CYCEXPAND,,OFF command, you cannot then expand the model by simply issuing another /CYCEXPAND command (for example, to specify an NREPEAT value for the number of repetitions). In such a case, you must specify /CYCEXPAND,,ON, which activates expansion using the previous settings (if any) or the default settings.

The command requires PowerGraphics and will turn PowerGraphics on (/GRAPHICS,POWER) if not already active. Any setting which bypasses PowerGraphics (for example, /PBF) also bypasses cyclic expansion; in such cases, the /CYCEXPAND command displays unprocessed real and imaginary results.

The CYCPHASE command uses full model graphics (/GRAPHICS,FULL) to compute peak values. Because of this, there may be slight differences between max/min values obtained with CYCPHASE, and those obtained via /CYCEXPAND, which uses power graphics (/GRAPHICS,POWER).

For PHASEANG = AMPLITUDE (or 360) with a cyclic full harmonic solution, the only appropriate coordinate system is the solution coordinate system (RSYS,SOLU).

Load case operations (LCOPER) are not valid during a cyclic expansion using /CYCEXPAND.

To learn more about analyzing a cyclically symmetric structure, see the Cyclic Symmetry Analysis Guide.