Engineering Solutions

Orientation Review

Orientation Review

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Orientation Review

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Use the Orientation Review tool to display/review and modify frequently used coordinate systems used in CAE analysis.

orientation_review_dialog

The following tabs can be accessed in the dialog:          

hmtoggle_plus1greyElemental System

In the Elemental system tab you can select 1D, 2D, or 3D elements and display the coordinate system.

Elemental systems are dependent on the solver type. For example, for Nastran and for quad elements the X axis is determined using the bisector of the diagonal line. Select the element and click Apply to show the system display. The mode element can be added and the display can be super imposed. Clicking Clear removes the information that you added, and clicking Clear All removes the system.  

orientation_review_dialog_elemental_system

hmtoggle_plus1greyMaterial System

orientation_review_dialog_material_system

By default the material system aligns with the C1 direction of the element edge. C1 is the direction from node 1 to node 2 of the element. You can super impose the elemental system on the same plot of the material system.  

elemental_system

The blue and green arrows represent the elemental system (x and y) and the red and brown arrows represent the material system (x and y)

hmtoggle_plus1greyPly Directions

orientation_review_dialog_plyl_directions

During CAD import of the composite data, each ply is associated with one or a separate system (one system for several plies or a system for each ply). You can select a ply and review its system. This is important to align the element normal to match the ply normal, or correct the ply angles if the normals are in the opposite direction.  

There are three function options:  

Fiber orientation

Fiber direction without the correction for drape.

Drape fiber orientation

Fiber direction with drape correction.

System

Ply system for each ply.

ply_system

The green arrows show the material X direction. The blue arrow shows the ply 5 fiber direction without drape. The red arrows shows ply 5 fiber direction with drape.

hmtoggle_plus1greyOrientation

In the Orientation tab you can display and correct element orientation. Element orientation is determined by the order of the nodes in the element connectivity. This is sometimes referred to as C1, C2, C3, or element local system.    

orientation_review_orientation_tab

display_normals

Display normal and reverse normal 2D elements

reverse_normals

Reverse normals. The element already selected during the display normal will be reversed.

c1_c2_c3_direction

C1, C2, C3 direction: This displays the element orientation of the nodes. C1 is the direction from node 1 to node 2 using the element connectivity order.

resequence_nodes_option

Resequence nodes: align C1 direction of 2D quad elements. Using the display C1 direction, some of the elements may not be aligned, as shown in the previous image. Select a guide element as the reference element and the rest of the element node connectivity will be changed to align the C1 direction.

reverse_1d_element_direction

Reverse 1D element direction. This function reverses the X direction (node 1 to node 2) of a 1D element. This image shows before reversing the elements.

reverse_1d_element_direction2

After reversing the elements

When the function is set to Align N1-N2 dir., you must select a selection method.

By element. Select an element with the correct orientation.
By edge_node. Select edge nodes with the correct direction.
By System. Select a system with the correct 1, 2, 3 direction.
Vector. Select a vector direction.

 

The orientation of the rest of the elements will be determined based on the orientation or direction of the selected entity.

 

hmtoggle_plus1grey Ply Normals

CAD based ply angles and orientation are transformed with respect to the element material system for analysis solvers. Most of the time you can correct the element normal to match the ply normal from the CAD. There are times when it is not possible to change the element normal to match the ply normal, as shown in the diagram below. In these cases, you need to change the ply angles with respect to the element normal without changing the element normal. For example, a +45 degree ply will become a -45 degree ply if the element normal and ply normal are in opposite directions.      

ply_normal_creation_diagram

ply_normal_element_normal

The ply normal does not match the element normal

The Ply normals tab lets you indicate which ply angles need to be reversed for which elements when they do not match the ply normal.

orientation_review_ply_normals

Perform the following steps:      

1.Select the single ply for which the element normal needs to be reversed.  
2.Select the elements that need to be reversed.  
3.Reverse the normal if they do not match.
4.Repeat these steps for each ply.

ply_reversed

The element normal for the ply is now reversed. Note that the actual element normal is not changed. The software takes a note (sets a flag internally) for a particular ply, and the angle needs to be reversed for that element, instead of reversing the normal. This is reflected in the solver data.