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Latest articles
Transient Removal of Initial Penetrations Using DPRFAC Parameter for SOFT=2 Contacts
Beginning LS-DYNA versions 971, a new option for SOFT=2 contact called DPRFAC in Optional Card ‘C’ in *CONTACT keyword allows transient removal of any …
Load Balance Checker for MPP LS-DYNA
A simple ‘C’ program is included to extract the processor based timing information from D3HSP file and output load balance summary. Future versions of …
MPP and Deformable to Rigid Switching
You may have read the previous post on deformable to rigid switching which works by turning a predefined set of deformable components into a rigidbody at a …
Load Balance in FMVSS 207/210 Simulations for MPP
Analyses involving automotive seat designs for loadcases such as FMVSS 207/210 has shown some poor load balance on compute nodes when using the default …
Initial Velocity in Local Coordinate System
In several loading situations, initial velocities are often defined along directions that do not coincide with the global coordinate system. In such cases …
Curve Extrapolation
Curves are used widely to define a XY data that are used by several entities in LS-DYNA. They help us to define either a time-dependent function, used in …
Limitations of Using LCSR for Strain-Rate Inclusion in MAT_024
The widely popular material model *MAT_PIECEWISE_LINEAR_PLASTICITY (MAT_024) supports various methods to include the strain-rate effects. One of the …
Bulk Viscosity for Shells and Solids in LS-DYNA
In any wave propagation code, such as LS-DYNA, which belongs to a family of ‘Hydro’ codes, bulk viscosity is essential to treat shocks. Smooth initial data …
Modeling Loading and Unloading Behavior in Seatbelt Materials
Seatbelt constitutive model, invoked by using *MAT_SEATBELT, in LS-DYNA provides features to model the loading and unloading characteristics from a …
Identifying Necking in Metals and Plastics
When characterizing materials such as Metals and Plastics in LS-DYNA, most constitutive models provide a yield criteria that accounts for a 3D state of …
Speeding up Simulations for Focused Studies
In several situations, simulation models (new or inherited), are quite often burderend with several expensive features that may have negligible effect on …
Initial Penetrations in Contact Interfaces
1. Introduction Contact definitions allow the modeling of interaction between one or more parts in a simulation model and have become a necessity in any …