Quality Index Cleanup Tools Secondary Panel

Use the Quality Index Cleanup Tools secondary panel to access tools that assist you in manually relocating nodes and optimizing element topology.

Location: Accessed by clicking cleanup tools from the Quality Index panel

The Quality Index Cleanup Tools secondary panel's layout changes dynamically depending on the cleanup tool you select. The list of cleanup tools is always displayed along the left-hand side of the panel. The criteria for the currently active cleanup tool displays in the second column, and the current composite Quality Index, patch checker, and action buttons display in the third column.


Figure 1.

Place Node Tool

Option Action
along surface / normal to surface Choose which direction the node will move.
along surface
Move the node along the plane or curvature of the surface.


Figure 2. Movement Along Surface. Notice that the node cannot normally exceed the edge of the mesh.
normal to surface
Move the node directly away from the surface in a normal direction.


Figure 3. Movement Normal to Surface
With the place node tool highlighted, click-and-drag a node to relocate it. The elements that depend on that node will dynamically adjust as you drag, resulting in a QI change.
allow movement out of boundary Move the nodes past the edges of a mesh boundary.


Figure 4. Movement Along Surface, Allowing Movement Out of Boundary
Note: Available when along surface is selected.
move midnodes Move the midnodes associated with the node you are moving.
Tip: Useful when working with second order elements.

Modify Hole and Washer Tool

Option Action
radial Alter the radius of a hole (and, optionally, the washer).
To alter the radius of the hole, click and drag a node. The element orientation remains constant, but the hole may become larger or smaller based on the input. There are additional controls to enable or disable automatic remeshing when altering the hole dimensions.


Figure 5.
radius: (and edit check box) Displays the current radius of the hole that the selected node belongs to. By default it is a display-only field.

If you do not want to click and drag a node, enable the edit checkbox to specify a desired radius. Once you click a node in the desired hole, the radius will change to the specified value.

angular Move the nodes around the edges of the hole without changing the hole diameter or the spacing between nodes.


Figure 6.
angle: (and edit check box) Displays the current angle of the hole that the selected node belongs to, relative to its original (unmodified) starting position. By default it is a a display-only field.

If you do not want to click and drag a node, enable the edit checkbox to specify a desired angle. Once you click a node in the desired hole, the angle will change to the specified value.

radial and angular: Simultaneously change the hole's radius and the orientation of nodes around its edge. Like the angular option, the node spacing remains proportionally consistent, though actual spacing will be scaled in accordance with changes in the hole radius.


Figure 7.
radial and angular: (and edit check boxes) Displays the current angle and radius of the hole that the selected node belongs to. By default they are both a display-only field.

If you do not want to click and drag a node, enable both edit checkboxes and specify a desired angle and radius. Once you click a node in the desired hole, the angle and radius will simultaneously change to the specified values.

circumferential Rotate the nodes along the circumference of the slot without altering the hole's size or shape/orientation.
Note: This option is primarily used on opening like slots. The capability works on enclosed slots or holes. It is not designed to work on slots with an opening.


Figure 8.
circumferential (and edit check box) Displays the current arc length of the hole that the selected node belongs to. By default it is a display-only field.

If you do not want to click and drag a node, enabled the edit checkbox and specify a desired arc length. Once you click a node in the desired hole, the arc length will change to the specified value.

link washers Change the radial or angular position of nodes, as well as drag and scale the washer nodes along with them. In order for the link washers option to work, you must enable the allow to move fixed and shared nodes checkbox in page 4 of the Quality Index panel.


Figure 9. Original Model


Figure 10. Link Washers Option Disabled


Figure 11. Link Washers Option Enabled
retain washer width Alter the radius of a hole without changing the width of a washer.
Clear this checkbox to change the radius of the hole and the washer simultaneously.


Figure 12. Original Model


Figure 13. Retain Washer Width Disabled


Figure 14. Retain Washer Width Enabled
Note: Available for radial and radial & angular changes, when the link washers checkbox is enabled.
remesh number of layers: To specify the number of washer layers to automatically remesh after you alter the node position, select this check box.

Swap Edge Tool

Use the Swap Edge tool to consider the elements to which the edge belongs, and find alternative orientations for it.


Figure 15.
Each time you click an edge, it switches to the next valid configuration. If an edge swap will not improve element quality, a message to that effect displays in the status bar. To force the swap anyways, click the edge a second time. Additional clicks will cycle through the possible edge positions. The number of possible edge positions depends on the types of elements involved.

For a pair of trias, there are two possible positions for their shared edge. For a pair of quads, there are three possible positions. For a quad and a tria, there are six possible positions.

Node Optimize Tool

Use the Node Optimize tool to automatically move a selected node to optimize the overall quality of its surrounding elements. The options along surface, normal to surface, and along and normal to surface work exactly as described for the place node tool. The only difference is that node optimize moves the node automatically, while place node requires you to choose the location manually.

To move the midnodes attached to the node you are optimizing, enable the with attached midnodes checkbox.
Tip: Useful when working with second order elements.


Figure 16. Select Node to Move. The mouse indicates the node that will be moved in each of the following examples.


Figure 17. Move Node Along Surface


Figure 18. Move Node Normal to Surface


Figure 19. Move Node Along and Normal to Surface

Element Optimize Tool

Use the Element Optimize tool to automatically optimize the shape of the selected element and the elements surrounding it. It is similar to Node Optimize, except that its effects are wider-spread.

To move the midnodes attached to the element you are optimizing, enabled the with attached midnodes checkbox.
Tip: Useful when working with second order elements.


Figure 20.

Smooth Tool

Use the Smooth cleanup tool to improve element quality in a surface-based mesh. This cleanup tool uses one or more algorithms to adjust node positions to moderate sharp variations in size or quality in adjacent elements, and to adjust the position of the free nodes of the selected shell elements to smooth out variations in element quality and size.

A node of a shell element is free if none of the following statements are true:
  • It is used by an element that was not selected.
  • It is selected as an anchor node.
  • It is attached to an edge, vertex, or meshing fixed point of a surface.
  • It is used by a 1D element (whether or not that element is selected).
  • It is not attached to a surface, but is on a feature line of the mesh of the selected plate or shell elements.
For any elements that are not associated to surfaces, HyperLife Weld Certification infers an approximation to the shape of the surface that most likely produced these elements.
Option Action
smooth: elements Select the element(s) you want to smooth.
anchor: nodes Select an anchor a node (for example, you may use an anchor node at a weld site).
mesh algorithm options Select a smooth function behavior.
autodecide
Calculate the lengths of all of the elements' edges to find the extreme values. If the ratio of smallest to largest is below a certain threshold, than autodecide will use the shape correcting algorithm. If the ratio of smallest to largest is above a certain threshold, than autodecide will use the size correcting algorithm.
size corrected
Moderate variations in element edge size through the mesh using a modified Laplacian over-relaxation that correctly handles a mixture of quad and tria elements.
shape corrected
Moderate variations in element aspect ratio through the mesh using a modified isoparametric-centroidal over-relaxation that correctly handles a mixtures of quad and tria elements.
QI optimization
Adjust the nodes to the target quality index value that you define in order to reduce the quality index of the selected elements.
Selecting QI optimization enables additional options.
keep nodes on geometry edges
Smooth nodes on shared edges by moving them along the edge, and not across.
recursive optimization procedure / single optimization procedure
Choose whether to run a single smoothing step (single optimization step), or multiple smoothing steps (recursive optimization procedure) until an internal convergence is reached.

Split/Collapse Edge Tool

Use the split/collapse edge cleanup tool to split or collapse the edges of elements in your model.

To use the split edge tool, left-click on an edge. HyperLife Weld Certification splits the elements that share the selected edge in a way that will achieve the optimum quality.


Figure 21.
To use the collapse tool, right-click on the edge you wish to collapse. HyperLife Weld Certification collapses the selected edge, as well as any edges that are associated with it.


Figure 22.

Drag Tria Element Tool

Use the drag tria element cleanup tool to drag a tria element to a different location in the model, or out of the model completely.

To use the drag tria element cleanup tool, left-click on a tria element and drag it to a desired location. HyperLife Weld Certification highlights the selected tria element in pink.


Figure 23.
To drag two tria elements together and merge them into one quad element, enable the merge trias checkbox.


Figure 24. Merge Trias Checkbox Enabled


Figure 25. Merge Trias Checkbox Disabled

Split Quad Element Tool

Use the split quad element cleanup tool to split a quad element into two tria elements.

To split a quad element, left-click on the quad element you wish to split. HyperLife Weld Certification splits the quad element into two tria elements.


Figure 26.

Combine Tria Elements Tool

Use the combine tria elements cleanup tool to combine two tria elements into one quad element.

To combine two tria elements, left-click on their shared edge. HyperLife Weld Certification combines the two tria elements into one quad element.


Figure 27.

Patch Checker Tool

Use the Patch Checker to review patches of failed elements, as well as quality results. Each patch contains failed element with layers of elements around it. To increase or decrease the number of layers, click + or - respectively. To see the next or previous patch, click next or prev respectively.

The Patch Checker displays the comp. QI value, the number of failed elements, and the percent of failed elements in each patch. To reduce the number of failed elements, use the Quality Index cleanup tools. Once you have corrected all of the elements in the patch, you can move on to the next patch. You will no longer be able to display the previous patch, as all elements are corrected.


Figure 28.

Command Buttons

Button Action
QI settings Return to the Quality Index Panel.
Undo Undo the most recent edit. Multiple levels of undo are available.
Redo Redo the most recently undone edit. Multiple levels of redo are available.
Save failed Save all of the elements deemed failed to memory. Use the extended entity selection menu of any elems selector in another panel to retrieve the list of failed elements and automatically select them.
Abort Discard all changes and return to the Quality Index panel with the mesh unchanged.
Return Keep all changes and return to the Quality Index panel.