COMSOL 6.2 - SizeExpression

model.component(<ctag>).mesh(<tag>).feature(<ftag>).set(property,<value>);

model.component(<ctag>).mesh(<tag>).feature(<ftag>).getType(property);

model.component(<ctag>).mesh(<tag>).feature(<ftag>).create(<ftag1>,"SizeExpression");

model.component(<ctag>).mesh(<tag>).feature(<ftag>).feature(<ftag1>).selection();

model.component(<ctag>).mesh(<tag>).feature(<ftag>).feature(<ftag1>).
set(property,<value>);

model.component(<ctag>).mesh(<tag>).feature(<ftag>).feature(<ftag1>).getType(property);

Use model.component(<ctag>).mesh(<tag>).create(<ftag>,"SizeExpression") to specify a mesh element size expression in the sequence. Use model.component(<ctag>).mesh(<tag>).feature(<ftag>).create(<ftag1>,"SizeExpression") to specify an element size expression for the feature <ftag> that can be any of the types Edge, FreeQuad, FreeTri, or FreeTet.

Use model.component(<ctag>).mesh(<tag>).feature(<ftag>).selection() or model.component(<ctag>).mesh(<tag>).feature(<ftag>).feature(<ftag1>).selection() to specify the geometric entity selection. If you do not specify any selection, the size expression feature is defined on all geometric entities.

You can use mesh.feature(<ftag>).importData() to reevaluate the size expression, taking an updated model into account.

The following properties are available.

Table 4-37: Feature Properties for SizeExpression.
Property	Value	Default	Description
adapsolnum	Array of integers>0	1	Solution number indices.
cellsize	Positive scalar	Geometry bounding box size / 25	Grid cell size.
elementspar	Positive scalar		Controls refinement if elselect = elements.
elselect	globalmin \| worst \| elements		Method to select elements to refine.
errorexpr	String		Error expression.
exprtype	size \| error	size	Type of expression for the adaptive mesh generation: an absolute size or an error expression.
evaltype	grid \| solution \| initialexpression	grid	Specification of mesh to evaluate on.
globalminparam	Positive scalar		Controls refinement if elselect = globalmin.
gridtype	cellresolution \| cellsize	cellresolution	Grid specification.
hmeshgrad	Scalar, 1.0 or greater	1.4	Maximum size field growth rate (1.4 means that the mesh can grow by 40%, for example).
horder	Double array	0	Error orders (see below).
mesh	auto \| tag of other mesh	auto	Mesh for evaluation when evaltype is initialcondition.
numcell	Integer	25	Number of cells per dimension.
selection	first \| last \| all \| manual	last	Solution selection: the first or last solution, all solutions, or manual, using weights and solution number indices in adapsolnum.
sizeexpr	String	Geometry bounding box size	Size expression to evaluate for the mesh size.
solution	String		The solution defining the mesh adaptation.
studystep	none \| tag path to study step	none	The study step to use. Available when evaltype is initialcondition.
updatecondition	A parameter name		Name of a parameter used to trigger an update.
weights	Double[] (positive values)	1.0	Weight for each selected solution.
worstpar	Positive scalar		Controls refinement if elselect = worst.

Table 4-37: Feature Properties for SizeExpression.

Solution number indices.

cellsize

Positive scalar

Geometry bounding box size / 25

Grid cell size.

elementspar

Positive scalar

Controls refinement if elselect = elements.

elselect

globalmin | worst | elements

Method to select elements to refine.

size | error

Type of expression for the adaptive mesh generation: an absolute size or an error expression.

evaltype

grid | solution | initialexpression

grid

Specification of mesh to evaluate on.

globalminparam

Positive scalar

Controls refinement if elselect = globalmin.

gridtype

cellresolution | cellsize

cellresolution

Grid specification.

hmeshgrad

Scalar, 1.0 or greater

1.4

Maximum size field growth rate (1.4 means that the mesh can grow by 40%, for example).

horder

Double array

Error orders (see below).

mesh

auto | tag of other mesh

auto

Mesh for evaluation when evaltype is initialcondition.

numcell

Integer

Number of cells per dimension.

selection

first | last | all | manual

last

Solution selection: the first or last solution, all solutions, or manual, using weights and solution number indices in adapsolnum.

sizeexpr

String

Geometry bounding box size

Size expression to evaluate for the mesh size.

solution

String

The solution defining the mesh adaptation.

studystep

none | tag path to study step

none

The study step to use. Available when evaltype is initialcondition.

updatecondition

A parameter name

Name of a parameter used to trigger an update.

weights

Double[] (positive values)

1.0

Weight for each selected solution.

worstpar

Positive scalar

Controls refinement if elselect = worst.

For the horder property, its value is automatically calculated in the adaptation algorithm. It is used only when the Element selection method is set to Rough global minimum.