ansys.mapdl.core.Mapdl.lcoper#

Mapdl.lcoper(oper='', lcase1='', oper2='', lcase2='', sweepang='', **kwargs)#

Performs load case operations.

Mechanical APDL Command: LCOPER

Parameters:
operstr

Valid operations are:

  • ZERO - Zero results portion of database ( LCASE1 ignored).

  • SQUA - Square database values ( LCASE1 ignored).

  • SQRT - Square root of database (absolute) values ( LCASE1 ignored).

  • LPRIN - Recalculate line element principal stresses ( LCASE1 ignored). Stresses are as shown for the NMISC items of the etable command for the specific line element type.

  • ADD - Add LCASE1 to database values.

  • SUB - Subtract LCASE1 from database values.

  • SRSS - Square root of the sum of the squares of database and LCASE1.

  • MIN - Compare and save in database the algebraic minimum of database and LCASE1.

  • MAX - Compare and save in database the algebraic maximum of database and LCASE1.

  • ABMN - Compare and save in database the absolute minimum of database and LCASE1 (based on magnitudes, then apply the corresponding sign).

  • ABMX - Compare and save in database the absolute maximum of database and LCASE1 (based on magnitudes, then apply the corresponding sign).

lcase1str

First load case in the operation (if any). See LCNO of the lcdef command. If ALL, repeat operations using all selected load cases ( lcsel ).

oper2str

Valid operations are:

  • MULT - Multiplication: LCASE1 * LCASE2

  • CPXMAX - This option does a phase angle sweep to calculate the maximum of derived stresses, equivalent strain, and principal strains for a complex solution where LCASE1 is the real part and LCASE2 is the imaginary part. The Oper field is not applicable with this option. Also, the lcabs and sumtype commands have no effect on this option. The value of S3 will be a minimum. Absolute maximum is obtained for component quantity. This option does not apply to derived displacement amplitude (USUM). Load case writing ( lcwrite ) is not supported. See POST1 and POST26 - Complex Results Postprocessing

lcase2str

Second load case. Used only with Oper2 operations.

sweepangstr

Sweep angle increment in degrees for phase sweep. Used only with Oper2 = CPXMAX. (Default = 1°)

Notes

lcoper operates on the database and one or two load cases according to:

  • Database = Database Oper ( LCASE1 Oper2 LCASE2 )

where operations Oper and Oper2 are as described above.

Absolute values and scale factors may be applied to the load cases before the operations ( lcabs, lcfact ). If LCASE1 is not specified, only operation Oper is performed on the current database. If LCASE2 is specified, operation Oper2 is performed before operation Oper. If LCASE2 is not specified, operation Oper2 is ignored.

Solution items not contained ( outres ) in either the database or the applicable load cases will result in a null item during a load case operation. Harmonic element data read from a result file load case are processed at zero degrees.

Load case combinations must be performed on load cases from the same results file. Combining load cases from different results files is not supported.

Load case combinations of element-based solutions are performed in the solution coordinate system, and the data resulting from load case combinations are stored in the solution coordinate system. The resultant data are then transformed to the active results coordinate system ( rsys ) when listed or displayed. Except in the cases of Oper = LPRIN, ADD, or SUB, you must use rsys,SOLU to list or display results. In the case of layered elements, the layer ( layer ) must also be specified.

If nodal-averaged results are a part of the load case combination, the resulting nodal-averaged result data are in the global Cartesian coordinate system. Furthermore, the resulting numerical values may differ from the same lcoper operation performed on the same data stored as element results. The SQUA, SQRT, LPRIN, and SRSS operations are not valid when applied to nodal averaged results. For more information, see Nodal-Averaged Results

Use the force command prior to any combination operation to correctly combine the requested force type.

If Oper2=CPXMAX, the derived stresses and strain calculation do not apply to line elements.

For details on using load case combination, see Creating and Combining Load Cases

For cyclic symmetry ( cyclic ), lcoper operates on the raw base and duplicate sector values. It cannot be used on the expanded values ( cycexpand ).