Cross Sections

Cross section entities store cross section definitions used in a crash analysis.

A cross section is defined by a set of nodes and elements. These sets can be explicitly defined in the entity or computed by intersecting a given geometry (plane, circle) with a set of elements or components.

Supported Solver Cards

Solver cards supported for cross sections.

LS-DYNA Cards

Card	Description
*DATABASE_CROSS_SECTION_PLANE(ID)	XsectionPlane
*DATABASE_CROSS_SECTION_SET(ID)	Define a cross section for resultant forces written to an ASCII file SECFORC.

PAM-CRASH 2G

No graphics are display for SECFO cards.

Card	Description
SECFO /
SECFO / NTYP = PLANE	Transmission force at cutting plane Graphics available.
SECFO / NTYP = CONTACT	Cumulated contact forces No graphics available.
SECFO / NTYP = LINK	Cumulated link forces No graphics available.
SECFO / NTYP = SECTION	Transmission force at section No graphics available.
SECFO / NTYP = SUPPORT	Support reaction force No graphics available.
SECFO / NTYP = VOLFRAC	Fraction of volume affected by a defined criterion No graphics available.
SECFO / NTYP = CONT_MS	Contact forces between Main and Secondary nodal groups No graphics available.
SECFO / NTYP = DETECT	Accumulated nodal mass in selected volume No graphics available.
SECFO / NTYPE = TIED_MS	Tied forces between main and secondary nodal groups (v2018)

Radioss Cards

Card	Description
/SECT	A section is a set of nodes and a set of elements. Note: Block Format Keyword
/SECT/CIRCLE	A section is a set of nodes and a set of elements. Sets are built automatically, by intersecting the concerned groups of elements with a disc. Note: Block Format Keyword
/SECT/PARAL	A section is a set of nodes and a set of elements. Sets are built automatically, by intersecting the concerned groups of elements with a parallelogram. Note: Block Format Keyword

Create Cross Sections

Create cross sections using the Cross Section Assistant.

Restriction: Available in the Radioss, LS-DYNA, PAM-CRASH 2G user profiles.

In the Model Browser, right-click and select Create > Cross Section from the context menu.
The Cross Section Assistant dialog opens.
In the Cross Section Name field, enter a name for the cross section.

Note: If Create Multiple is enabled, the cross section name defines the prefix of each cross section created.
In the Cross Section Type field, select the type of cross section to create.
In the Entity Selection field, use the entity selector to select the mesh that will be cut by the cross section.
Select the Create Multiple checkbox to create multiple cross sections simultaneously.

Note: When this checkbox is enabled, a cross section path definition will replace the Base Node and Normal Definition parameters.
If you are creating multiple cross sections, in the Cross Section Path field, use the entity selector to select a node path for the creation of each cross section.
If you are creating a single cross section:
1. In the Base Node field, define the location of the cross section.
  Manually enter the coordinates of the cross section, or click select the base node in the graphics area.
2. In the Normal Direction field, define the normal of the cutting plane to be used for the generation of the cross section.
  Manually enter the coordinates of the vector, or click to pick two or three nodes.
Click Create.

HyperMesh automatically fits the cross section to the selected mesh. If you are using the Radioss user profile, the cross section time history Output Blocks is automatically created.

Figure 1. Radioss Cross Section	Figure 2. LS-DYNA Cross Section