Page 88 - The Combined Finite-Discrete Element Method
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ALTERNATIVE IMPLEMENTATION OF THE POTENTIAL CONTACT FORCE 71
A square of Contact
regular grid potential
Boundary of
discrete
element
Figure 2.43 Contact force potential specified at nodes of a single square of a regular grid.
Figure 2.44 Boundary points for contact force potential defined over the domain of a discrete
element of a general shape.
discrete element shown in Figure 2.42, only 35 numbers are needed to represent both the
shape and contact potential.
Processing of contact can be employed in either a distributed fashion, by resolving the
contact of couples of contacting squares each belonging to a different discrete element, or
a simpler approach can be adopted, in which the contact force is resolved as a concentrated
contact force. For this purpose, a set of boundary points on the surface (boundary) of a
discrete element is specified as shown in Figure 2.44.
The contact is resolved by considering interaction of each of the boundary points with
respective squares of the regular grid (Figure 2.45). For a given point p, the potential is
