33.2.1 Continuum particle elements
Product: Abaqus/Explicit
References
Overview
Continuum particle elements:
can be used only in explicit dynamic analyses;
must have one node only;
have one integration point;
can be initialized similarly to continuum elements; and
are fully filled with material.
Typical applications
Continuum particle elements (PC3D) are useful for simulations involving material that undergoes extreme deformation such as open-surface fluid flow or obliteration/fragmentation of solid structures. They are defined using only one node; however, the element centered at a given node (particle) receives contributions from all particles within a sphere of influence whose radius is commonly referred to as the smoothing length. The smoothed particle hydrodynamic (SPH) formulation determines at every increment of the analysis the connectivity associated with a given particle. Since nodal connectivity is not fixed, severe element distortion is avoided and, hence, the formulation allows for very high strain gradients.
The 1-node PC3D element is used to define points both on the surface and in the interior of the body to be modeled. You define these nodes similarly to mass elements, and the nodes can be placed in space the same as the nodes of a regular brick mesh. A smoothed particle hydrodynamic mesh is typically a uniformly spaced grid of elements that conforms to the shape of the body being modeled.
For more information, see “Smoothed particle hydrodynamics,” Section 15.2.1.
Defining the element's section properties
You must associate a solid section definition with a set of continuum particle elements. The section definition provides the material associated with the PC3D elements.
As part of the solid section definition, you can define a characteristic length. This characteristic length, not to be confused with the smoothing length, is used to compute the particle volume. The volume is assumed to be a cube whose sides are equal to twice the specified characteristic length.
| Input File Usage: | *SOLID SECTION, ELSET=element_set_name characteristic length associated with the particle volume |
where the ELSET parameter refers to a set of particle elements. |