Create an element. You must specify the shape of the element that you want to create, and you must select the nodes in the order appropriate for that element shape.

Delete elements. You have the option of deleting any nodes that would be left unassociated with any elements once the selected elements are deleted.

Flip the surface normal direction of shell elements.

Collapse a selected edge of quadrilateral or triangular elements. Collapsing an edge is useful for removing slivers from quadrilateral and triangular elements, as shown in Figure 41–1. When you preview a tetrahedral boundary mesh, you can collapse selected edges of the triangular elements to remove slivers. In some cases, when you create an all-quadrilateral mesh using the advancing front algorithm, ABAQUS/CAE may generate quadrilateral elements with a short edge. You can collapse the short edge and create a well-formed triangular element, as shown in Figure 41–2.

Split a selected edge of a quadrilateral or triangular element into two parts. You can split the edge at its midpoint, or you can click on the location of the split. You can use a combination of tools to clean up your mesh. For example, Figure 41–3 illustrates how you can split an edge and then collapse the resulting edge to remove a long narrow triangular element. If you are editing a native mesh in the Mesh module, ABAQUS/CAE projects the new node on the native geometry. As a result, you can use this tool for improving a coarse mesh around curved edges, as shown in Figure 41–4.

Swap the diagonal of a pair of adjacent triangular elements, as shown in Figure 41–5. You can swap the diagonal of either first- or second-order adjacent triangular elements if they are the same order. In addition, the adjacent triangular elements must have consistent normals. If necessary, you can flip the normals to make them consistent.

Split a quadrilateral element into two triangular elements, as shown in Figure 41–6. You cannot split a 5-node quadrilateral element, and you cannot split a gasket element.

Combine two adjacent triangular elements into one quadrilateral element, as shown in Figure 41–7. You can combine either first- or second-order elements, but you cannot combine a combination of both. In addition, you can combine elements only if the adjacent triangular elements have consistent normals. If necessary, you can flip the normals to make them consistent.

Orient the stack direction of a continuum shell, cohesive, or gasket mesh. You can stack only hexahedral, wedge, and quadrilateral elements to form a continuum shell, cohesive, or gasket mesh. As a result, you can use this tool to orient the stack direction of only hexahedral, wedge, and quadrilateral elements. If you have assigned second-order gasket elements to the region, you must first change the assignment to conventional elements before you reorient the stack direction. You can then convert the region back to a gasket mesh by reassigning second-order gasket elements.