How can I export a calculation file when the mesh data has different element types?

GiD Customization
1

Hello, GiD developer,

Using the CustomLib utility,
I want to export the connectivity data for a mesh model containing a mixture of triangles and quadrilaterals.
What is the way to do this?

In the attachment QuadsTets.gid.zip, only triangles can be exported, quadrilaterals not exported.

The problemtype of QuadsTets.gid: cmas2d_customlib.gid
My GiD version: 16.0.11
My PC: Windows 11 64bit.

Regards,

QuadsTets.gid.zip (9.2 KB)

QuadsTets_captured
QuadsTets_captured1079×508 105 KB

2

The demo problemtype ‘Examples/cmas2d_customlib’ is only prepared to calculate with triangles, then the problemtype is restricting the creation of groups of elements of other types (with the optional parameter: ov_element_types=“triangle”)

<condition n="Shells" pn="Shells" ov="surface" ovm="element" ov_element_types="triangle" icon="darkorange-shellfish-18" groups_icon="yelowish-group" help="Select your material and the surfaces related to it">

It is possible to allow for example surface elements of type triangle an also quadrilateral with (ov_element_types=“triangle,quadrilateral”, or not restrict any type of element)

You attached model has condition ‘Shells’ with a group of a surface meshed with triangles, and other group with a surface meshed with quadrilaterals, but because of the restriction, in mesh the quadrilaterals don’t belong to the group (if you draw the group any quadrilateral is draw or listed)

With this modification you can load again the problemtype, assign the conditions to the surfaces, mesh, and calculate, and they are written the quads (with 4 connectivities an the triangles with 3 connectivities),

Connectivities:
Element Node(1) Node(2) Node(3) Material
1 21 20 24 25 2
2 17 16 20 21 2
3 13 12 16 17 2
4 20 19 23 24 2
5 16 15 19 20 2
6 12 11 15 16 2
7 19 18 22 23 2
8 15 14 18 19 2
9 11 10 14 15 2
10 13 9 12 1
11 2 1 3 1
12 2 3 4 1
13 7 10 11 1
14 12 9 8 1
15 8 9 6 1
16 8 6 5 1
17 12 8 11 1
18 4 3 5 1
19 7 11 8 1
20 4 5 6 1
21 5 7 8 1

but the calculation program is not ready for this input.

Note: the writing.tcl code do this

set element_formats [list {“%10d” “element” “id”} {“%10d” “element” “connectivities”} {“%10d” “material” “MID”}]

customlib::WriteConnectivities $elements_conditions $element_formats active

but customlib::WriteConnectivities is a convenience proc (defined in \scripts\customlib_extras\customlib_extras.tcl)

the true final command is doing is

set formats [list “Shells Auto1” “%10d %10d %10d %10d 1\n” “Shells Auto2” “%10d %10d %10d %10d %10d 2\n”]
GiD_WriteCalculationFile connectivities -elements_faces all $formats

the elements of the group named “Shells Auto1” provide a format with 1 integer for the element id, 3 integers for its triangle elements, and a hardcoded “1” for the material id, an the group named “Shells Auto2” a format with 1 integer for the element id, 4 integers for its quadrilateral elements, and a hardcoded “2” for the material id

The syntax of GiD_WriteCalculationFile is explained in the GiD customization manual

https://gidsimulation.atlassian.net/wiki/spaces/GCM/pages/2410447127/WriteCalculationFile

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