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git-svn-id: svn://svn.icms.temple.edu/lammps-ro/trunk@2130 f3b2605a-c512-4ea7-a41b-209d697bcdaa

This commit is contained in:
sjplimp 2008-10-01 16:01:49 +00:00
parent ab26116253
commit 4f52fa4aed
2 changed files with 54 additions and 28 deletions
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41
doc/fix_indent.html
View File

@ -23,15 +23,19 @@
<LI>one or more keyword/value pairs may be appended
<LI>keyword = <I>sphere</I> or <I>cylinder</I> or <I>vel</I> or <I>rstart</I> or <I>units</I>
<LI>keyword = <I>sphere</I> or <I>cylinder</I> or <I>plane</I> or <I>vel</I> or <I>rstart</I> or <I>units</I>
<PRE> <I>sphere</I> args = x y z R
x,y,z = initial position of center of indenter
x,y,z = initial position of center of indenter (distance units)
R = sphere radius of indenter (distance units)
<I>cylinder</I> args = dim c1 c2 R
dim = x or y or z = axis of cylinder
dim = <I>x</I> or <I>y</I> or <I>z</I> = axis of cylinder
c1,c2 = coords of cylinder axis in other 2 dimensions (distance units)
R = cylinder radius of indenter (distance units)
<I>plane</I> args = dim pos side
dim = <I>x</I> or <I>y</I> or <I>z</I> = plane perpendicular to this dimension
pos = position of plane in dimension x, y, or z (distance units)
side = <I>lo</I> or <I>hi</I>
<I>vel</I> args = vx vy vz
vx,vy,vz = velocity of center of indenter (velocity units)
<I>rstart</I> value = R0
@ -54,8 +58,8 @@ fix 2 flow indent 10.0 cylinder z 0.0 0.0 10.0 units box
atoms that touch it, so it can be used to push into a material or as
an obstacle in a flow.
</P>
<P>The indenter can either be spherical or cylindrical. You must set
one of those 2 keywords.
<P>The indenter can either be spherical or cylindrical or planar. You
must set one of those 3 keywords.
</P>
<P>A spherical indenter exerts a force of magnitude
</P>
@ -70,12 +74,20 @@ radius of the indenter. The force is repulsive and F(r) = 0 for <I>r</I> >
distance from the atom to the center axis of the cylinder. The
cylinder extends infinitely along its axis.
</P>
<P>If the <I>vel</I> keyword is specified, the center (or axis) of the
spherical (or cylindrical) indenter will move during the simulation,
based on its initial position (x,y,z) and the specified (vx,vy,vz).
Note that if you do multiple runs, the initial position of the
indenter (x,y,z) does not change, so it will continue to move at the
specified velocity.
<P>A planar indenter is really an axis-aligned infinite-extent wall
exerting the same force on atoms in the system, where <I>r</I> is the
distance from the plane. If the <I>side</I> parameter of the plane is
specified as <I>lo</I> then it will indent from the lo end of the
simulation box, meaning that atoms with a coordinate less than the
plane's current position will be pushed towards the hi end of the box.
Vice versa if <I>side</I> is specified as <I>hi</I>.
</P>
<P>If the <I>vel</I> keyword is specified, the center (or axis or position) of
the spherical (or cylindrical or planar) indenter will move during the
simulation, based on its initial position (x,y,z) and the specified
(vx,vy,vz). Note that if you do multiple runs, the initial position
of the indenter (x,y,z) does not change, so it will continue to move
at the specified velocity.
</P>
<P>If the <I>rstart</I> keyword is specified, then the radius of the indenter
is a time-dependent quantity. R0 is the value assigned at the start
@ -94,9 +106,10 @@ choice affects not only the indenter's physical geometry, but also its
velocity and force constant since they are defined in terms of
distance as well.
</P>
<P>IMPORTANT NOTE: You should insure the indenter's extent does not
overlap a periodic boundary, either for a fixed indenter, or one that
moves. No check for such overlaps is performed by the code.
<P>IMPORTANT NOTE: For spherical and cylindrical indenters, you should
insure the indenter's extent does not overlap a periodic boundary,
either for a fixed indenter, or one that moves. No check for such
overlaps is performed by the code.
</P>
<P><B>Restart, fix_modify, output, run start/stop, minimize info:</B>
</P>

41
doc/fix_indent.txt
View File

@ -16,14 +16,18 @@ ID, group-ID are documented in "fix"_fix.html command :ulb,l
indent = style name of this fix command :l
k = force constant for indenter surface (force/distance^2 units) :l
one or more keyword/value pairs may be appended :l
keyword = {sphere} or {cylinder} or {vel} or {rstart} or {units} :l
keyword = {sphere} or {cylinder} or {plane} or {vel} or {rstart} or {units} :l
{sphere} args = x y z R
x,y,z = initial position of center of indenter
x,y,z = initial position of center of indenter (distance units)
R = sphere radius of indenter (distance units)
{cylinder} args = dim c1 c2 R
dim = x or y or z = axis of cylinder
dim = {x} or {y} or {z} = axis of cylinder
c1,c2 = coords of cylinder axis in other 2 dimensions (distance units)
R = cylinder radius of indenter (distance units)
{plane} args = dim pos side
dim = {x} or {y} or {z} = plane perpendicular to this dimension
pos = position of plane in dimension x, y, or z (distance units)
side = {lo} or {hi}
{vel} args = vx vy vz
vx,vy,vz = velocity of center of indenter (velocity units)
{rstart} value = R0
@ -45,8 +49,8 @@ Insert an indenter within a simulation box. The indenter repels all
atoms that touch it, so it can be used to push into a material or as
an obstacle in a flow.
The indenter can either be spherical or cylindrical. You must set
one of those 2 keywords.
The indenter can either be spherical or cylindrical or planar. You
must set one of those 3 keywords.
A spherical indenter exerts a force of magnitude
@ -61,12 +65,20 @@ A cylindrical indenter exerts the same force, except that {r} is the
distance from the atom to the center axis of the cylinder. The
cylinder extends infinitely along its axis.
If the {vel} keyword is specified, the center (or axis) of the
spherical (or cylindrical) indenter will move during the simulation,
based on its initial position (x,y,z) and the specified (vx,vy,vz).
Note that if you do multiple runs, the initial position of the
indenter (x,y,z) does not change, so it will continue to move at the
specified velocity.
A planar indenter is really an axis-aligned infinite-extent wall
exerting the same force on atoms in the system, where {r} is the
distance from the plane. If the {side} parameter of the plane is
specified as {lo} then it will indent from the lo end of the
simulation box, meaning that atoms with a coordinate less than the
plane's current position will be pushed towards the hi end of the box.
Vice versa if {side} is specified as {hi}.
If the {vel} keyword is specified, the center (or axis or position) of
the spherical (or cylindrical or planar) indenter will move during the
simulation, based on its initial position (x,y,z) and the specified
(vx,vy,vz). Note that if you do multiple runs, the initial position
of the indenter (x,y,z) does not change, so it will continue to move
at the specified velocity.
If the {rstart} keyword is specified, then the radius of the indenter
is a time-dependent quantity. R0 is the value assigned at the start
@ -85,9 +97,10 @@ choice affects not only the indenter's physical geometry, but also its
velocity and force constant since they are defined in terms of
distance as well.
IMPORTANT NOTE: You should insure the indenter's extent does not
overlap a periodic boundary, either for a fixed indenter, or one that
moves. No check for such overlaps is performed by the code.
IMPORTANT NOTE: For spherical and cylindrical indenters, you should
insure the indenter's extent does not overlap a periodic boundary,
either for a fixed indenter, or one that moves. No check for such
overlaps is performed by the code.
[Restart, fix_modify, output, run start/stop, minimize info:]