IDs that are duplicated within element and property groups for the LS-DYNA user profile are supported in HyperMesh beginning with version 8.0. For example, elements like beam and shell can now be imported without renumbering even if they have the same ID. Although it is not recommended to use duplicate IDs, this support has been implemented for greater flexibility for users who need to import models that already contain duplicate IDs. This support helps to preserve data integrity between HyperMesh and the solver by mimicking the solver's data rules. This support is provided by several means:

LS-DYNA data decks that have duplicated IDs are no longer automatically renumbered by HyperMesh. The ID numbers for elements and properties are preserved regardless of duplication. However, renumbering is still in effect for other entity types.

In an FE input, if the FE overwrite option is selected, IDs are overwritten only within the same ID group.

From the Preferences drop down menu, select the Meshing options panel to see the allow duplicate IDs option. This can be selected to enable the duplication of IDs across pools of new elements or properties you create in HyperMesh. For example, ID 1 can be used for a shell element and a solid element. However ID 1 cannot be used for two shell elements. By default, the option is not selected and HyperMesh never creates entities with the same ID during renumbering or meshing, and uses a sequential numbering scheme. With the exception of importing decks, the HyperMesh support of duplicate IDs must be manually activated.

When you attempt to select properties or elements for editing or deletion and you choose the by id option, you now must select an ID group (such as ELEMENT_SHELL or ELEMENT_BEAM) in addition to the ID, if the ID is present in more than one group. This selection is required to identify specific IDs if there is duplication across ID groups. For example, if both beam and shell have element ID 1, and you select an element by ID=1, a pop-up window appears that allows you to select between the two available groups that contain ID 1.

 

See Also:

Options Panel