This is a post by Guest Author Satish Pathy who works full time for LSTC In *MAT_FABRIC, element formulation 4 & 14 will allow you to input unloading curve for the material. Recently in a model it was noticed, that when a large compressive stress develops in the fibers, lsdyna would release some of these…
Control cards are often handy to overwrite local values. A good example would be if we need all parts to use a certain element formulation THEORY which is specified in *CONTROL_SHELL. As with any global control cards that manipulate local values, the global values specified in *CONTROL keywords are used ONLY if the local values…
LS-DYNA allows the modeling of rigid-bodies by assigning any part with the MAT_RIGID material law (MAT_020). This is by far the most easiest method available when compared with all finite element codes. When using MAT_RIGID, there are three distinct ways to model a rigid part and they are briefly explaine below. 1. Finite Element based…
Wishing everyone a very happy new year.
In traditional explicit analysis, there is no convergence criteria that is checked for each time step. However, in Implicit calculations, incremental displacements are evaluated such that a displacement norm and the energy norm are within a pre-defined tolerance before convergence is assumed to be obtained. This is the so-called iterative scheme in Implicit Non-Linear Analyses…
I am pleased to inform that Marsha Victory has continued the sponsorship of D3VIEW blog hosting. If this blog has been of help to you, please take a moment to thank Marsha. She can be contacted at marsha@lstc.com. Thanks very much, Marsha, for your support.
When nodes are involved in both contact (penalty) and prescribed motion, contact failure is expected to occur. This is because the boundary conditions are always processed after all the contacts are handled that results in nodal accelerations being updated to enforce the boundary conditions. I will soon publish some examples to illustrate this phenomenon.
Discrete beams, like discrete springs, require valid mass at the nodes to compute the timestep. Unlike continuum based elements, the length of the discrete beams, are not used in the timestep calculations. Hence realistic density in the discrete beam material model must be used. There are two methods this can be achived. Density (RHO) in…
You can download the LS-DYNA 971 r4 Manual (PDF, 11.5 Mb) Update The broken link has been fixed
