Block2D Command

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The block2D command generates meshes of quadrilateral elements in two or three dimensions. In three dimensions, a two-dimensional surface appropriate for shell analysis is generated.

block2d $nx $ny $e1 $n1 element elementArgs {
1 $x1 $y1 <$z1>
2 $x2 $y2 <$z2>
3 $x3 $y3 <$z3>
4 $x4 $y4 <$z4>
<5> <$x5> <$y5> <$z5>
<6> <$x6> <$y6> <$z6>
<7> <$x7> <$y7> <$z7>
<8> <$x8> <$y8> <$z8>
<9> <$x9> <$y9> <$z9>
}

$nx number of elements in the local x directions of the block
$ny number of elements in the local y directions of the block
$e1 element from which the mesh generation will start
$n1 node from which the mesh generation will start
element string defining which quadrilateral elements is being used (quad, ShellMITC4, bbarQuad, or enhancedQuad)
elementArgs list of data parameters for element being used
{$x1, .... ,$x9}, {$y1, .... ,$y9} coordinates of the block elements in two dimensions
{$z1, .... $z9} coordinate of the block elements in third dimension (optional, default=0.0)

NOTE:

1. Only the first four nodes (1-4) are required. Nodes 5-9 are used to generate curved meshes. The user may specify any combination of nodes 5-9, omitting some of them if desired.

2. This command recognizes variable substitutions when the command arguments are placed in quotes.


EXAMPLE:

block2D 16 4 1 1 quad "1 PlaneStrain2D 1" {
1 0 0
2 40 0
3 40 10
4 0 10
}

Node numeration of a quadrilateral element:

QuadEle.PNG