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DOPTPRM

PARAM1

VAL1

PARAM2

VAL2

PARAM3

VAL3

PARAM4

VAL4

PARAM5

VAL5

Etc …

Field

Contents

PARAMi

Parameter name. See below for valid names.

VALi

Parameter value.

(Real, Integer, or Label)

APPROX

Switch to select the approximation type for stress/strain responses of shells, composites and 1D elements.

FULL or REDUCED
Default = FULL

BARCON

Controls the internal constraints of PBARL and PBEAML properties during optimization.

REQUIRED or EXTENDED
Default = REQUIRED

BKLOCAL1

Determines the buckling zone of the model.

0.0 ≤ Real ≤ 1.0
Default = 0.5

BKLOCAL2

Specifies the maximum number of elements to represent the buckling zone for local modes.

Integer ≥ 0
No default

CHECKER

Controls the checkerboard-like element wise density distribution.

0 or 1
Default = 0

CONTOL

Controls the percentage value of the constraint violation tolerance.

Real > 0.0
Default = 1.0%

DDVOPT

Control options for discrete design optimization.

1, 2, or 3
Default = 1

DELSHP

The initial fractional move limit for topography/shape design variables (fractional difference between the upper and lower bounds).

Real > 0.0
Default = 0.2

DELSIZ

The initial fractional move limit for size design variables.

Real > 0
Default = 0.5

DELTOP

The initial fractional move limit for topology and free-size design variables.

Real > 0
Default = 0.5

DESMAX or MAXITER

Defines the maximum number of design iterations.

Integer > 0
Default = 30, or if MINDIM is defined, default = 80

DISCRETE

Discreteness parameter. Influences the tendency for elements in a topology optimization to converge to a material density of 0 or 1.

Real > 0.0

Defaults:

1.0 – general default.

2.0 - for solid dominant structures with member size control and no manufacturing constraints.

DISCRT1D

Discreteness parameter for 1D elements.

Real > 0.0
Default = DISCRETE

ESLMAX

Maximum number of outer design loops in the design of Multi-body dynamic systems and for nonlinear optimization using ESLM.

Integer > 0
Default = 30

ESLSOPT

Controls the time step screen strategy in the design of multi-body dynamic systems.

<0 or 1>
Default = 1

ESLSTOL

Controls the tolerance for screening out time steps in the design of multi-body dynamic systems.

0.0 < Real < 1.0
Default = 0.3

GBUCK

Controls the global buckling constraint.

YES, NO, 1 or 0
Default = 0

MATINIT

Defines the initial material fraction.

Real between 0.0 and 1.0

MAX_BUCK

Controls the maximum number of buckling eigenvalues to be considered for each buckling subcase in an optimization problem.

Integer > 0
Default = 15

MINDENS

Sets the minimum element material density.

Real > 0.0
Default = 0.01

MINDIM

Specifies the minimum diameter of members formed in a topology optimization.

Real > 0.0
Default = no minimum member size control

MMCHECK

Parameter to ensure a checkerboard-free solution.

Integer = 0 or 1
Default = 0

NESLEXPD

Specifies the number of time steps retained for optimization from each EXPDYN subcase. At each time step, one ESL is generated.

Integer > 0
Default = 20

NESLIMPD

Specifies the number of time steps retained for optimization from each IMPDYN subcase. At each time step, one ESL is generated.

Integer > 0
Default = 20

NESLNLGM

Specifies the number of time steps retained for optimization from each NLGEOM subcase. At each time step, one ESL is generated.

Integer > 0
Default = 1

OBJTOL

Relative convergence criterion.

Real > 0.0
Default = 0.005

For Lattice Structure Optimization, the default is set to 0.001.

OPTMETH

Options to choose the optimization algorithm.

MFD, SQP, DUAL, BIGOPT, DUAL2,
Default = See descriptions

PNORM

Specifies the value of the power (or penalty) p, used in the Stress NORM method for stress response calculation in Lattice Structure Optimization.

Real ≥ 1.0
Default = 6.0

REMESH

Parameter to activate the remeshing process.

Integer = 0 or 1
Default = 0

SHAPEOPT

Optional parameter to select an alternative shape optimization algorithm.

<1 or 2>
Default = 1

TMINPLY

Defines the minimum ply thickness allowed for all plies of PCOMP’s selected by DSIZE or DTPL design variable definitions.

0.0 < Real < min(Ti)

TOPDISC

Activates the improved discrete topology optimization formulation.

YES or NO
Default = NO