Adams Basic Package > Adams View > View Command Language > executive_control > executive_control set numerical_integration_parameters

executive_control set numerical_integration_parameters

Description:

Parameter	Value Type	Description
model_name	Existing model	Specifies the model to be modified. You use this parameter to identify the existing model to be affected with this command.
integrator_type	GSTIFF, WSTIFF, DSTIFF, ABAM, CPBDF, HASTIFF, SI2_GSTIFF	Specifies the integrator type to be used
solver_type	CALAHAN, HARWELL	Specifies the Solver type
error_tolerance	Real	Specifies the error tolerance. Should be greater than 0.
pattern_for_jacobian	Yes/No	Specifies the pattern for jacobian. Can take up to 10 boolean values.
maxit_corrector_iterations	Integer	Should be an integer greater than 0
hinit_time_step	Real	Should be a real number greater than 0
hmin_time_step	Real	Should be a real number greater than 0
hmax_time_step	Real	Should be a real number greater than 0
adaptivity	Real	Specify the adaptivity
scale	Real	Specify the scale
kmax_integrator_order	Integer	Specify the integrator order. Integer specified should be greater than 0 and less than or equal to 12.
interpolate	Yes/No	Indicates whether interpolation is allowed. That is, indicates whether the integrator can choose integration steps independent of output steps and the interpolate results for the output step times.
reconcile	ALL, DISPLACEMENTS, NONE	Corrects interpolated results before Adams writes them to the output files to satisfy the constraint equations.
repartition_threshold	Real number	Allows some control of the re-partitioning of coordinates into independent and dependent coordinates.
corrector_resolution_factor	Real	Specifies the corrector resolution factor
fixed_iterations	Integer	Specify the number of iterations per integration step for the GSTIFF and HHT method. Should be an integer greater than 0.
hratio	Integer	Specify the number of times the step size goes into the output sampling rate (that is, hratio=dtout/h) for the GSTIFF and HHT method. Should be an integer greater than 0 and it is relevant if fixed_iterations is specified.
max_error	Real	Specifies the amount of error above which the user would like Adams Solver to stop trying to solve the problem for the GSTIFF and HHT method. Value should be positive real and it is relevant if fixed_iterations is specified.

Extended Definition:

1. You may identify a model by typing its name or by picking it from the screen.

If the model is not visible on the screen, you must type the name. You may also find it convenient to type the name even if the model is displayed.

You must separate multiple model names by commas.

If the model is visible in one of your views, you may identify it by picking on any of the graphics associated with it.

You need not separate multiple model picks by commas.

2. The values for RECONCILE can be:

DISPLACEMENTS: Only the displacements are corrected to satisfy the constraints.

ALL: The displacements are corrected to satisfy the constraints and the velocities and accelerations are corrected to satisfy the constraint derivatives.

NONE: The integration step size is adjusted to force the integrator to compute the solution at every output step. In this situation,

INTERPOLATE must be set to NO.

3. In general, for efficiency reasons, the coordinates are re-partitioned whenever:

■ A matrix inverse condition number gets too small

■The displacement iterations do not converge

■A part rotation occurs

■A matrix becomes numerically singular, or

■The unit energy ratio is less than its original value times the value of REPARTITION_THRESHOLD.

Cautions:

1. Note that interpolation is not yet available when the EXECUTIVE_CONTROL SET DYNAMICS_PARAMETERS BDF_PARAMETER command specifies FIXED or VARIABLE coefficients for the PREDICTOR_COEFFICIENTS argument.