ansys.mapdl.core.Mapdl.pdef#

Mapdl.pdef(lab='', item='', comp='', avglab='', **kwargs)#

Interpolates an item onto a path.

Mechanical APDL Command: PDEF

Parameters:

labstr

Label assigned to the resulting path item (8 characters maximum). This item may be used as input for other path operations.

itemstr

Label identifying the item for interpolation. Valid item labels are shown in PDEF - Valid Item and Component Labels below. Some items also require a component label.

compstr

Component of the item (if required). Valid component labels are shown in PDEF - Valid Item and Component Labels below.

avglabstr

Option to average across element boundaries:

• AVG - Average element results across elements (default).

• NOAV - Do not average element results across elements. If the parameter DISCON = MAT on the pmap command, this option is automatically invoked.

Notes

Defines and interpolates a labeled path item along a predefined path ( path ). Path item results are in the global Cartesian coordinate directions unless transformed ( rsys ). A path item must be defined before it can be used with other path operations. Additional path items may be defined from the pvect, pcalc, pdot, and pcross commands. Path items may be listed ( prpath ) or displayed ( plpath, plpagm ). A maximum number of path items permitted is established by the nSets argument specified with the path command.

When you create the first path item ( pdef or pvect ), the program automatically interpolates four path items which are used to describe the geometry of the path. These predefined items are the position of the interpolated path points (labels XG, YG, and ZG) in global Cartesian coordinates, and the path length (label S). For alternate methods of mapping the path geometry (to include, for example, material discontinuity) see the pmap command. These items may also be listed or displayed with the prpath, plpath, and plpagm commands.

If specifying that load case operations act on principal/equivalent stresses ( sumtype,PRIN), derived quantities (principal and equivalent stresses/strains) will be zero for path plots. A typical use for such a case involves mode combinations in a response spectrum analysis.

The number of interpolation points on the path is defined by the nDiv argument on the path command. See Mapping Nodal and Element Data onto the Path pdef,STAT to list the path item labels. Use pdef,CLEAR to erase all labeled path items, except the path geometry items (XG, YG, ZG, S).

See also Mapping Results onto a Path

PDEF - Valid Item and Component Labels#

Item	Comp	Description
Valid item and component labels for nodal degree of freedom results are:
U	X, Y, Z, SUM	X, Y, or Z structural displacement or vector sum.
ROT	X, Y, Z, SUM	X, Y, or Z structural rotation or vector sum.
TEMP[ PDEF_temp ]		Temperature.
PRES		Pressure.
VOLT		Electric potential.
MAG		Magnetic scalar potential.
V	X, Y, Z, SUM	X, Y, or Z fluid velocity or vector sum.
A	X, Y, Z, SUM	X, Y, or Z magnetic vector potential or vector sum.
CONC		Concentration.
CURR		Current.
EMF		Electromotive force drop.
Valid item and component labels for element results are:
S	X, Y, Z, XY, YZ, XZ	Component stress.
“	1, 2, 3	Principal stress.
“	INT, EQV	Stress intensity or Equivalent stress.
EPTO	X, Y, Z, XY, YZ, XZ	Component total strain (EPEL + EPPL + EPCR).
“	1, 2, 3	Principal total strain.
“	INT, EQV	Total strain intensity or total equivalent strain.
EPEL	X, Y, Z, XY, YZ, XZ	Component elastic strain.
“	1, 2, 3	Principal elastic strain.
“	INT, EQV	Elastic strain intensity or elastic equivalent strain.
EPPL	X, Y, Z, XY, YZ, XZ	Component plastic strain.
“	1, 2, 3	Principal plastic strain.
“	INT, EQV	Plastic strain intensity or plastic equivalent strain.
EPCR	X, Y, Z, XY, YZ, XZ	Component creep strain.
“	1, 2, 3	Principal creep strain.
“	INT, EQV	Creep strain intensity or creep equivalent strain.
EPTH	X, Y, Z, XY, YZ, XZ	Component thermal strain.
“	1, 2, 3	Principal thermal strain.
“	INT, EQV	Thermal strain intensity or thermal equivalent strain.
EPSW		Swelling strain.
NL	SEPL	Equivalent stress (from stress-strain curve).
“	SRAT	Stress state ratio.
“	HPRES	Hydrostatic pressure.
“	EPEQ	Accumulated equivalent plastic strain.
“	PSV	Plastic state variable.
“	PLWK	Plastic work/volume.
For contact results PowerGraphics is applicable for 3D models only.
CONT	STAT PDEFcontstat	Contact status.
“	PENE	Contact penetration.
“	PRES	Contact pressure.
“	SFRIC	Contact friction stress.
“	STOT	Contact total stress (pressure plus friction).
“	SLIDE	Contact sliding distance.
“	GAP	Contact gap distance.
“	FLUX	Total heat flux at contact surface.
TG	X, Y, Z, SUM	Component thermal gradient or vector sum.
TF	X, Y, Z, SUM	Component thermal flux or vector sum.
PG	X, Y, Z, SUM	Component pressure gradient or vector sum.
EF	X, Y, Z, SUM	Component electric field or vector sum.
D	X, Y, Z, SUM	Component electric flux density or vector sum.
JC	X, Y, Z, SUM	Component conduction current density or vector sum (for elements that support conduction current calculation)
H	X, Y, Z, SUM	Component magnetic field intensity or vector sum.
B	X, Y, Z, SUM	Component magnetic flux density or vector sum.
CG	X, Y, Z, SUM	Component concentration gradient or vector sum
DF	X, Y, Z, SUM	Component diffusion flux density or vector sum
FMAG	X, Y, Z, SUM	Component electromagnetic force or vector sum.
ETAB	Lab	Any user-defined element table label (see etable command).
BFE	TEMP	Applied and calculated temperatures along a defined path.
SPL		Sound pressure level.
SPLA		A-weighted sound pressure level (dBA).

For SHELL131 and SHELL132 elements with KEYOPT(3) = 0 or 1, use the labels TBOT, TE2, TE3,…, TTOP instead of TEMP.

For more information on the meaning of contact status and its possible values, see Reviewing Results in POST1