Distribution
Use the Distribution node () to specify the distribution of mesh elements along an edge or along the sweep direction. It is possible to add Distribution nodes both as global nodes and as local nodes. If there are several Distribution nodes in the sequence with a nonempty selection intersection, the mesher uses properties corresponding to the last Distribution node in the sequence. Distribution properties always override properties defined by Size nodes sharing the same selections.
To add a Distribution attribute,
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In the Mesh toolbar, click the Distribution () button.
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Right-click a Mesh node and select Distribution to add it as a global node.
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Right-click a mesh Generators node and select Distribution to add it as a subnode to an operation node.
See Global vs. Local Attributes.
Geometric Entity Selection
Define the geometric entities where you want to specify a distribution. Choose Manual from the Selection list to select the entities in the Graphics window or choose All domains/boundaries/edges to select all available entities of that level.
Choose the level of the geometry from the Geometric entity level list (only available for global attributes in 3D):
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Choose Domain to specify the domains for the distribution. Choose Manual in the Selection list to select the domains in the Graphics window, choose a named selection to refer to a previously defined selection, or choose All domains to select all domains.
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Choose Edge to specify the edges for the distribution. Choose Manual from the Selection list to select the edges in the Graphics window, choose a named selection to refer to a previously defined selection, or choose All edges to select all edges.
The name of this section changes depending on the dimension of the component. The names are Edge Selection (local attributes in 3D), Boundary Selection (2D), or Domain Selection (1D), respectively. For global attributes in 3D, the name is Geometric entity level.
Distribution
There are three main types of distribution methods that you select from the Distribution type list:
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Select Explicit to use an explicit, user-defined element distribution. To define the distribution of mesh elements, enter a vector-valued expression defining a strictly increasing sequence of nonnegative numbers (using comma-separated numbers) in the Relative placement of vertices along edge field, specifying the relative arc length values of the mesh vertices along the edge or boundary. Select the Reverse direction check box to reverse the direction of the explicit distribution.
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Select Fixed number of elements to use a fixed number of mesh elements, which you enter into the Number of elements field. This is the default option.
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Select Predefined to specify properties of a predefined distribution method that can be either an exponentially or a linearly increasing or decreasing element size; see below for details.
Settings for the Predefined Distribution Type
In the Number of elements field, enter the number of elements (the default is 5 elements). To specify the ratio in size between the last element and first element in the distribution, use the Element ratio field (the default value is 1.0; that is, the first and the last elements have the same size). From the Growth rate list, select Linear for an element distribution based on an arithmetic sequence or select Exponential for an element distribution based on a geometric sequence. Select the Symmetric distribution check box to get a symmetric distribution of elements. The Element ratio will then define the ratio between the element in the middle of the distribution and the last element. Select the Reverse direction check box to switch the element distribution to the opposite direction along the edge or boundary. If you have specified several edges in the selection, the Reverse direction check box refers to the edge in the selection with the lowest entity number (the primary edge). For the other edges, their direction (with respect to the distribution) is such that the rotation with respect to the primary edge is minimized.
For tutorials where Distribution is used, see:
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Swept Meshing of a Bracket Geometry:
Application Library path COMSOL_Multiphysics/Meshing_Tutorials/bracket_swept_mesh.
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Using Meshing Sequences:
Application Library path COMSOL_Multiphysics/Meshing_Tutorials/meshing_sequence.
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Meshing Operations and Attributes
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Mapped
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Swept