Size

) to specify the size of mesh elements. It is possible to add Size nodes both as global nodes and as local nodes. If there are several Size nodes in the sequence with a nonempty selection intersection, the mesher uses properties corresponding to the last Size node in the sequence.

A meshing sequence corresponding to a nonempty geometry contains a Size node at the first position in the sequence. This Size node, referred to as the default Size node, is defined for the entire geometry and cannot be removed. To override the mesh size settings defined by this Size node, add another Size node to the sequence.

To add this node as a global node, right-click a node and select . To add this as a subnode, right-click a mesh Generators node and select . Also see Global vs. Local Attributes.

Geometric Entity Selection


	This section is not available for the default Size node.

In this section you define the geometric entities where you want to specify a size. Choose the level of the geometry from the list:

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Choose to specify the size for the entire geometry.

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Choose to specify the domains for the size specification. Choose from the list to select the domains in the window or choose to select all domains.

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Choose to specify the boundaries for the size specification. Choose from the list to select the boundaries in the window or choose to select all boundaries.

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Choose (3D only) to specify the edges for the size specification. Choose from the list to select the edges in the window or choose to select all edges. This option is only available in 3D.

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Choose to specify the points for the size specification. Choose from the list to select the points in the window or choose to select all points. This option is only available in 2D and 3D.

Element Size

Different types of physics typically require different mesh resolutions. You can use the list to adapt the element sizing to a specific physics area or application. The default values of the parameters under will be adjusted according to the selected options in the and lists. The list contains the following options:

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The default element size is and set as . See Controlling the Mesh Size Using Attributes and Predefined Mesh Element Sizes for details about the options. This automatically determines the parameters that you can otherwise customize under .

Select if you want to change the value for any parameters in the section.

Element Size Parameters

This section is available when is selected as the . Specify all element size parameters using numerical values or user-defined parameters.


	Except for the default Size node, if you select a Custom element size above, the check boxes are automatically added next to each field. Click to select a check box to activate, and edit, the corresponding parameter.

The following parameters control the mesh element size (the parameters where you define a size use the geometry’s length unit). Defaults vary based on whether it is a default node or not. Edit the default values as required for the following fields:

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: Use this parameter to limit the allowed element size, for example, if you want to limit the maximum element size to a fraction of the wavelength to make sure that the wave propagation is fully resolved. By using a parametric sweep to vary the maximum element size, you can solve the model using meshes with different mesh density to study how it affects the solution.

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: Use this parameter to specify the minimum allowed element size. You can use this value to, for example, prevent the generation of many elements around small curved parts of the geometry. If some details of the geometry are smaller than the minimum element size, the mesh will contain elements of a smaller size in order to resolve the geometry. This parameter is not available in 1D.

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: Use this parameter to determine the maximum rate at which the element size can grow from a region with small elements to a region with larger elements. The value must be greater or equal to one. For example, with a maximum element growth rate of 1.5, the element size can grow by at most 50% (approximately) from one element to another.

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. Use this parameter to determine the size of boundary elements compared to the curvature of the geometric boundary (that is, the ratio between the boundary element size and the curvature radius). The curvature radius multiplied by the curvature factor, which must be a positive scalar, gives the maximum allowed element size along the boundary. A smaller curvature factor gives a finer mesh along curved boundaries. This parameter is not available in 1D.

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: Use this parameter to control the number of layers of elements that are created in narrow regions (approximately). The value must be a nonnegative scalar. A higher value gives a finer mesh in narrow regions. If the value of this parameter is less than one, the mesh generator might create elements that are anisotropic in size in narrow regions.


	There is no guarantee that all mesh elements in the generated mesh strictly fulfill the size constraints given by the specified element size parameters.


	It is not possible to use a coarser mesh size setting on a geometric entity adjacent to a higher dimensional entity with a finer mesh size setting; the finer setting on a geometric entity overrides the coarser setting on its boundary. A warning is given when coarser settings are overridden.

For a tutorial about adjusting the mesh size, see

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Adjusting the Element Size for the Unstructured Mesh Generator:
Application Library path .

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Using Meshing Sequences:
Application Library path .

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Meshing Operations and Attributes

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Free Tetrahedral

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Free Triangular

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Free Quad