HyperWorks Tools, Tips & Tricks

Altair Engineering GmbH Tel.: +49 (0)7031 / 6208-0 Tech Support: hwsupport@altair.de Calwer Straße 7, D-71034 Böblingen E-Mail: information@altair.de Web: www.altairhyperworks.de 04/2011

HM: Tool to visualize and adapt element orientation (node order)

With this tool, you can easily adapt the orientation of Quads or Hexas.

Usually the goal is to get an aligned element systems, which means a regular

orientation of the node order.

Shell elements: the origin is the centroid. The displayed x axis direction is the bisection of the diagonals

(N1->N3 and N4->N2). The y axis is the cross product of the element normal and x.

Solid elements: the origin is the centroid. The displayed z axis is the direction from the centroid of the

bottom (N1-N4) to the centroid of the top face (N5-N8). X axis is the (projected) direction from the

centroid of the front face (N1,N5,N8,N4) to the centroid of the back face (N2,N3,N7,N6), and y axis is

the cross product of z and x.

This is the definition which is used in Nastran and Optistruct, and Radioss Bulk (disregarding the

material orientation angle), but note that it is different from Abaqus. For Radioss Block, it’s slightly

different but still indicating the correct node order.

Each system is visualized by three plot elements sharing the color of the related global axis.

Installation:

The TCL script can be invoked by adding a button to the utility page, a keyboard shortcut or manually

from the mini toolbar:

It will add an additional Tab:

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HyperWorks Tools, Tips & Tricks

Altair Engineering GmbH Tel.: +49 (0)7031 / 6208-0 Tech Support: hwsupport@altair.de Calwer Straße 7, D-71034 Böblingen E-Mail: information@altair.de Web: www.altairhyperworks.de 04/2011

1) Show systems Display element systems for a given selection. If solid and Shell elements are selected, it will

only display one kind (the first found element is crucial to make the decision).

2) Define orientation element To define a reference element in order to orient the mesh later, you may select one shell or solid

element. The type and the id of the element is shown at the right of the selector afterwards.

3) Modify orietation element You can orient the reference element to the intended orientation by swapping the node order.

For solids, “clockwise” and “anti-clockwise” is related to the bottom face (xy-plane).

4) Orient mesh You can orient either all attached elements or a certain selection.

Note that “attached” is restricted to displayed elements, but not to the selected reference element

type. So you might have to mask connector- or other 1D elements to prevent “bridges” to undesired

elements.

5) Delete visualization To remove the visualization elements

Additional Features:

You can adapt the first lines of the TCL script.

1) Create Vectors instead of plot elements Line 3-5 of the TCL file contain ###swap the comment to create vectors instead of plotels.

variable type element ;

# variable type "vector"

After activating the last line (by moving the “#” to the line above) the tool creates vectors.

2) Modifying the length of the visualization entities. Straight below (line 7 -9), you find

variable xScale 0.4 ; # scale factor for x relative to element size

variable yScale 0.7 ; # scale for y in relation to x

variable zScale 0.4 ; # scale for z in relation to x

Set these values in order to change the size of the displayed axes.