Case 1F Sandbox with Two Groups

Contents

This example is the geometry for a sandbox experiment in which a 20mm layer of sand overlies a 10mm layer of silicon on the right hand side of the model, while the sand rests on the base on the left hand side of the model. The total length of the model is 200mm and the length of the silicon layer is 150mm. Two groups are required, one for the sand and one for the silicon, and each group is defined using a single surface. Both surfaces are defined via a series of straight lines. An unstructured mesh is generated with a constant element size of 1.5mm.

HM_mesh_001_Case1F_01.

Problem Definition with Point and Line Numbers

(Point numbers shown in Red, Line numbers shown in black)

The data and result files for the project are in directory: mesh_001\Exercises\Case 1F

Data for geometry definition

Nodal_data

Seven points are defined with coordinates:

Point	X-Coordinate (mm)	Y-Coordinate (mm)	Z-Coordinate (mm)
1	0.0	0.0	0.0
2	200.0	0.0	0.0
3	200.0	30.0	0.0
4	0.0	30.0	0.0
5	50.0	0.0	0.0
6	50.0	10.0	0.0
7	200.0	10.0	0.0

Geometry_line

Eight Linear geometry lines are defined as shown in the problem definition.

Geometry_surface

Two Geometry_surface data structure define are defined

Data File

* Geometry_surface NUM=1

! ---------------------------------

lines IDM=6

1 7 8 4 5 6

* Geometry_surface NUM=2

! ---------------------------------

lines IDM=4

2 3 8 7

Geometry surface 1 defines the sand and Geometry Surface 2 defines the Silicon.

Data for Group Definition

Two Group_data data structures are defined, one for the sand and one for the silicon, and both are defined as active.

Data File

* Group_data NUM=1

! ---------------------------------

Group_name "sand"

Element_type "TPM3V"

Surfaces IDM=1

* Group_data NUM=2

! ---------------------------------

Group_name "Silicon"

Element_type "TPM3V"

Surfaces IDM=1

Group 1 is named "Sand" and is defined using the TPM3V (Triangle Plane Membrane with 3 nodes using the average Volume formulation). The geometry is defined by surface 1.

Group 2 is named "Silicon" and is defined using the TPM3V (Triangle Plane Membrane with 3 nodes using the average Volume formulation). The geometry is defined by surface 2.

* Group_control_data

! ---------------------------------

Group_numbers IDM=2

1 2

Active_geomechanical_groups IDM=2

1 1

Define groups 1 and 2 as active

Results

The generated mesh for a default mesh size of 1.5 mm is shown below

HM_mesh_001_Case1F_02.

Mesh for Sandbox Example