8. External Loadstep Predictor

Warning

The external loadstep predictor is for implicit analyses only.

Production-ready loadstep predictor types are available in the Sierra/SM User Guide. The LOADSTEP PREDICTOR command block controls the behavior of the predictor that is used to predict the solution at the beginning of a new load step. This command block is placed in the SOLVER scope.

The EXTERNAL, EXTERNAL_FIRST and TANGENT predictor types are special use capabilities currently under development.

BEGIN LOADSTEP PREDICTOR
  TYPE = <string>EXTERNAL|EXTERNAL_FIRST|TANGENT
END [LOADSTEP PREDICTOR]

The tangent predictor is selected with the TANGENT option, which is useful in combination with the tangent preconditioner. This type of predictor uses the tangent preconditioner to estimate the next load step’s solution.

at new load steps. For instance, the external predictor file can come from the results output of a previous model run that included the command OUTPUT EXTERNAL PREDICTOR VARIABLES in the output block, i.e.:

BEGIN RESULTS OUTPUT
  OUTPUT EXTERNAL PREDICTOR VARIABLES
END [RESULTS OUTPUT]

If you would like to try the external predictor, please contact Sierra support for more information. at new load steps. For instance, the external predictor file can come from the results output of a previous model run that included the command OUTPUT EXTERNAL PREDICTOR VARIABLES in the output block, i.e.:

BEGIN RESULTS OUTPUT
  OUTPUT EXTERNAL PREDICTOR VARIABLES
END [RESULTS OUTPUT]

If you would like to try the external predictor, please contact Sierra support for more information.