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Updated doc pages for pair body rounded/polygon and rounded/polyhedra

This commit is contained in:
Trung Nguyen 2018-07-13 14:34:50 -05:00
parent 21f749243a
commit 8447d8dd91
2 changed files with 24 additions and 12 deletions
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16
doc/src/pair_body_rounded_polygon.txt
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@ -18,8 +18,6 @@ mu = normal friction coefficient during gross sliding
delta_ua = multiple contact scaling factor
cutoff = global separation cutoff for interactions (distance units), see below for definition :pre
NOTE: what does gross sliding mean?
[Examples:]
pair_style body/rounded/polygon 20.0 5.0 0.0 1.0 0.5
@ -38,7 +36,7 @@ body particles.
This pairwise interaction between rounded polygons is described in
"Fraige"_#Fraige, where a polygon does not have sharp corners, but is
rounded at its vertices by circles centered on each vertex with a
specified diameter. The edges of the polygon are defined bewteen
specified diameter. The edges of the polygon are defined between
pairs of adjacent vertices. The circle diameter for each polygon is
specified in the data file read by the "read data"_read_data.html
command. This is a 2d discrete element model (DEM) which allows for
@ -47,7 +45,7 @@ multiple contact points.
Note that when two particles interact, the effective surface of each
polygon particle is displaced outward from each of its vertices and
edges by half its circle diameter. The interaction forces and
energies bewteen two particles are defined with respect to the
energies between two particles are defined with respect to the
separation of their respective rounded surfaces, not by the separation
of the vertices and edges themselves.
@ -65,7 +63,15 @@ explains how contact is defined? Do we need an equation(s) that
explain what the params in pair style and coeff mean, for damping and
spring constants? Or do we just want to reference the paper for that?
NOTE: say something about no frictional history ?
In "Fraige"_#Fraige, the tangential friction force between two particles
that are in contact is modeled differently prior to gross sliding
(i.e. static friction) and during gross-sliding (kinetic friction).
The latter takes place when the tangential deformation exceeds
the Coulomb frictional limit. In the current implementation, however,
we do not take into account frictional history, i.e. we do not keep track
of how many time steps the two particles have been in contact
nor calculate the tangential deformation. We assume that gross sliding
takes place right when two particles are in contact.
The following coefficients must be defined for each pair of atom types
via the "pair_coeff"_pair_coeff.html command as in the examples above,

20
doc/src/pair_body_rounded_polyhedron.txt
View File

@ -16,9 +16,7 @@ c_n = normal damping coefficient
c_t = tangential damping coefficient
mu = normal friction coefficient during gross sliding
delta_ua = multiple contact scaling factor
cutoff = global sepration cutoff for interactions (distance units), see below for definition :pre
NOTE: what does gross sliding mean?
cutoff = global separation cutoff for interactions (distance units), see below for definition :pre
[Examples:]
@ -39,16 +37,16 @@ This pairwise interaction between rounded polyhedra is described in
"Wang"_#Wang, where a polyhedron does not have sharp corners and
edges, but is rounded at its vertices and edges by spheres centered on
each vertex with a specified diameter. The edges if the polyhedron
are defined bewteen pairs of adjacent vertices. Its faces are defined
are defined between pairs of adjacent vertices. Its faces are defined
by a loop of edges. The sphere diameter for each polygon is specified
in the data file read by the "read data"_read_data.html command. This
is a discrete element model (DEM) which allows for multiple contact
points.
Note that when two particles interaact, the effective surface of each
Note that when two particles interact, the effective surface of each
polyhedron particle is displaced outward from each of its vertices,
edges, and faces by half its sphere diameter. The interaction forces
and energies bewteen two particles are defined with respect to the
and energies between two particles are defined with respect to the
separation of their respective rounded surfaces, not by the separation
of the vertices, edges, and faces themselves.
@ -66,7 +64,15 @@ explains how contact is defined? Do we need an equation(s) that
explain what the params in pair style and coeff mean, for damping and
spring constants? Or do we just want to reference the paper for that?
NOTE: say something about no frictional history ?
In "Wang"_#Wang, the tangential friction force between two particles
that are in contact is modeled differently prior to gross sliding
(i.e. static friction) and during gross-sliding (kinetic friction).
The latter takes place when the tangential deformation exceeds
the Coulomb frictional limit. In the current implementation, however,
we do not take into account frictional history, i.e. we do not keep track
of how many time steps the two particles have been in contact
nor calculate the tangential deformation. We assume that gross sliding
takes place right when two particles are in contact.
The following coefficients must be defined for each pair of atom types
via the "pair_coeff"_pair_coeff.html command as in the examples above,