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5.1 physical_  constants (alpha)
5.2 parts (release)
5.2.1 quadrature_  options (beta)

5 flex_models (release)

The flex_models object holds all flex_model objects, identified by user defined identifiers. A flex_model defines a Flex Representation Model, which pulls in U-spline geometry and associates materials and quadratures with it.

Name

 

Type

 

Description

 

Default

label

 

STRING

 

User defined identifier for this model definition.

 

physical_constants (alpha) [optional]

 

SUB OBJECT

 

See linked documentation

 

database_name

 

STRING

 

The file name for a U-spline geometry (*.cf) file. Do not include the extension.

 

geom

small_cell_volume_ratio [optional] (beta)

 

DOUBLE

 

The interior volume to total volume ratio that determines if a cell considered a small cell. Functions with support only on small cells are removed from the system and represented by neighboring large cell functions. An input value less than or equal to will deactivate basis conditioning.

 

0.0

parts (release)

 

LIST

 

Each spatial domain in the geometry file that must have a material assigned should be listed here. Each association goes under a user defined identifier.

 

Example Usage:

flex_models: [ { label: "flex_inf", database_name: "geom", small_cell_volume_ratio: 0, parts: [ { part: "cframe", material: "cast_iron", material_model: "elastic", quadrature_options: { quadrature: "QP1"} } ] } ]

5.1 physical_constants (alpha)

Name

 

Type

 

Description

 

Default

stefan_boltzmann (alpha)

 

DOUBLE

 

The Stefan--Boltzmann constant, used in radiation boundary conditions on heat conduction.

 

absolute_zero (alpha)

 

DOUBLE

 

The absolute zero value in the chosen temperature scale.

 

5.2 parts (release)

Each spatial domain in the geometry file that must have a material assigned should be listed here. Each association goes under a user defined identifier.

Name

 

Type

 

Description

 

Default

label [optional]

 

STRING

 

User defined identifier for this flex model part

 

part

 

STRING

 

User defined identifier of the geometric part to use in this model.

 

material

 

STRING

 

The user defined identifier of the material.

 

material_model

 

“elastic” | “neohookean” | “neohookean_isotropic_plasticity” | “mooney_rivlin” | “isotropic_heat_conduction”

 

Defines the material model of the user defined material

 

quadrature_options (beta) [optional]

 

SUB OBJECT

 

See linked documentation

 

Example Usage:

parts: [ { part: "cframe", material: "cast_iron", material_model: "elastic", quadrature_options: { quadrature: "QP1"} } ]

5.2.1 quadrature_options (beta)

Name

 

Type

 

Description

 

Default

quadrature [optional] (beta)

 

“QP1” | “QP0” | “Q1” | “Q2” | “Q3” | “Q4” | “Q5” | “Q6” | “Q7” | “Q8” | “Q9” | “Q10”

 

Quadrature type enumeration. The quadrature type determines the point layout over a patch or patch element. The schemes following the pattern “Q#” specify that a Gauss quadrature scheme with #-points will be used. The schemes following the pattern “QP#” specify that a Gauss quadrature scheme with -points will be used, where is the degree of the patch's or patch element's basis.

 

QP1

optimized_cut_quadrature_strategy [optional] (beta)

 

“match_uncut” | “reduce_from_uncut” | “match_basis”

 

Strategy to choose the degree of accuracy for quadrature on cut cells. The default strategy of reduce_from_uncut chooses quadrature rules with similar numbers of points as those used on uncut cells, as specified by quadrature; it has lower formal accuracy (integrating tensor products of monomials up to degree for uncut quadrature Q), but is a good default choice for practical calculations. The strategy match_uncut matches the formal accuracy of the quadrature on uncut cells, but is significantly more costly. The strategy match_basis chooses a rule that exactly integrates the basis functions; this is equivalent to reduce_from_uncut if the uncut cells use the default quadrature of QP1, but may differ for other choices of uncut quadrature.

 

reduce_from_uncut

optimized_cut_quadrature_degree [optional] (beta)

 

NONNEGATIVE INTEGER

 

If provided, this value overrides optimized_cut_quadrature_strategy by specifying an explicit polynomial degree of accuracy for optimized quadrature rules on cut cells.

 

optimization_method [optional] (beta)

 

“tet_pruning” | “grid_doubling” | “linear_programming”

 

Specifies the preferred method of quadrature generation for cut cells. If the preferred method fails on a particular cell, the other methods will be used in an attempt to recover.

 

tet_pruning

optimization_residual_tolerance [optional] (beta)

 

DOUBLE

 

The absolute residual tolerance used in quadrature optimization on cut cells. A smaller value will result in a more accurate quadrature rule, but may increase the time to compute quadrature rules for cut cells.

 

1e-12

optimization_lawson_hanson_solve_completion [optional]

 

true|false

 

An experimental option that controls the convergence behavior of quadrature optimization. For best results it is recommended to set this value to true. If set to true this causes each iteration of quadrature optimization to solve to the highest accuracy possible. The results at each iteration are then checked against the optimization_residual_tolerance to determine if a sufficient rule has been found. If this value is set to false then the optimization_residual_tolerance is passed to the solve at each iteration and can cause the solve step to terminate more quickly which can result in faster execution and a lower number of quadrature points. However the quality and accuracy of the resulting rule may be suspect.

 

true

tessellation_option [optional]

 

STRING

 

Tessellation identifier that defines options for tessellation