Page Menu
Home
c4science
Search
Configure Global Search
Log In
Files
F80320441
pair_peri_lps.cpp
No One
Temporary
Actions
Download File
Edit File
Delete File
View Transforms
Subscribe
Mute Notifications
Award Token
Subscribers
None
File Metadata
Details
File Info
Storage
Attached
Created
Sat, Aug 31, 03:32
Size
18 KB
Mime Type
text/x-c
Expires
Mon, Sep 2, 03:32 (2 d)
Engine
blob
Format
Raw Data
Handle
20338199
Attached To
rLAMMPS lammps
pair_peri_lps.cpp
View Options
/* ----------------------------------------------------------------------
LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator
http://lammps.sandia.gov, Sandia National Laboratories
Steve Plimpton, sjplimp@sandia.gov
Copyright (2003) Sandia Corporation. Under the terms of Contract
DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government retains
certain rights in this software. This software is distributed under
the GNU General Public License.
See the README file in the top-level LAMMPS directory.
------------------------------------------------------------------------- */
/* ----------------------------------------------------------------------
Contributing author: Mike Parks (SNL)
------------------------------------------------------------------------- */
#include "math.h"
#include "stdlib.h"
#include "string.h"
#include "pair_peri_lps.h"
#include "atom.h"
#include "domain.h"
#include "lattice.h"
#include "force.h"
#include "update.h"
#include "modify.h"
#include "fix.h"
#include "fix_peri_neigh.h"
#include "comm.h"
#include "neighbor.h"
#include "neigh_list.h"
#include "memory.h"
#include "error.h"
#include "update.h"
using
namespace
LAMMPS_NS
;
/* ---------------------------------------------------------------------- */
PairPeriLPS
::
PairPeriLPS
(
LAMMPS
*
lmp
)
:
Pair
(
lmp
)
{
for
(
int
i
=
0
;
i
<
6
;
i
++
)
virial
[
i
]
=
0.0
;
no_virial_fdotr_compute
=
1
;
single_enable
=
0
;
ifix_peri
=
-
1
;
nmax
=
0
;
s0_new
=
NULL
;
theta
=
NULL
;
bulkmodulus
=
NULL
;
shearmodulus
=
NULL
;
s00
=
alpha
=
NULL
;
cut
=
NULL
;
// set comm size needed by this Pair
// comm_reverse not needed
comm_forward
=
1
;
// for passing dilatation (theta)
}
/* ---------------------------------------------------------------------- */
PairPeriLPS
::~
PairPeriLPS
()
{
if
(
ifix_peri
>=
0
)
modify
->
delete_fix
(
"PERI_NEIGH"
);
if
(
allocated
)
{
memory
->
destroy
(
setflag
);
memory
->
destroy
(
cutsq
);
memory
->
destroy
(
bulkmodulus
);
memory
->
destroy
(
shearmodulus
);
memory
->
destroy
(
s00
);
memory
->
destroy
(
alpha
);
memory
->
destroy
(
cut
);
memory
->
destroy
(
theta
);
memory
->
destroy
(
s0_new
);
}
}
/* ---------------------------------------------------------------------- */
void
PairPeriLPS
::
compute
(
int
eflag
,
int
vflag
)
{
int
i
,
j
,
ii
,
jj
,
inum
,
jnum
,
itype
,
jtype
;
double
xtmp
,
ytmp
,
ztmp
,
delx
,
dely
,
delz
;
double
xtmp0
,
ytmp0
,
ztmp0
,
delx0
,
dely0
,
delz0
,
rsq0
;
double
rsq
,
r
,
dr
,
rk
,
evdwl
,
fpair
,
fbond
;
int
*
ilist
,
*
jlist
,
*
numneigh
,
**
firstneigh
;
double
d_ij
,
delta
,
stretch
;
evdwl
=
0.0
;
if
(
eflag
||
vflag
)
ev_setup
(
eflag
,
vflag
);
else
evflag
=
vflag_fdotr
=
eflag_global
=
eflag_atom
=
0
;
double
**
f
=
atom
->
f
;
double
**
x
=
atom
->
x
;
int
*
type
=
atom
->
type
;
int
nlocal
=
atom
->
nlocal
;
double
*
vfrac
=
atom
->
vfrac
;
double
*
s0
=
atom
->
s0
;
double
**
x0
=
atom
->
x0
;
double
**
r0
=
((
FixPeriNeigh
*
)
modify
->
fix
[
ifix_peri
])
->
r0
;
tagint
**
partner
=
((
FixPeriNeigh
*
)
modify
->
fix
[
ifix_peri
])
->
partner
;
int
*
npartner
=
((
FixPeriNeigh
*
)
modify
->
fix
[
ifix_peri
])
->
npartner
;
double
*
wvolume
=
((
FixPeriNeigh
*
)
modify
->
fix
[
ifix_peri
])
->
wvolume
;
// lc = lattice constant
// init_style guarantees it's the same in x, y, and z
double
lc
=
domain
->
lattice
->
xlattice
;
double
half_lc
=
0.5
*
lc
;
double
vfrac_scale
=
1.0
;
// short-range forces
int
newton_pair
=
force
->
newton_pair
;
int
periodic
=
domain
->
xperiodic
||
domain
->
yperiodic
||
domain
->
zperiodic
;
inum
=
list
->
inum
;
ilist
=
list
->
ilist
;
numneigh
=
list
->
numneigh
;
firstneigh
=
list
->
firstneigh
;
// loop over neighbors of my atoms
// need minimg() for x0 difference since not ghosted
for
(
ii
=
0
;
ii
<
inum
;
ii
++
)
{
i
=
ilist
[
ii
];
xtmp
=
x
[
i
][
0
];
ytmp
=
x
[
i
][
1
];
ztmp
=
x
[
i
][
2
];
xtmp0
=
x0
[
i
][
0
];
ytmp0
=
x0
[
i
][
1
];
ztmp0
=
x0
[
i
][
2
];
itype
=
type
[
i
];
jlist
=
firstneigh
[
i
];
jnum
=
numneigh
[
i
];
for
(
jj
=
0
;
jj
<
jnum
;
jj
++
)
{
j
=
jlist
[
jj
];
j
&=
NEIGHMASK
;
delx
=
xtmp
-
x
[
j
][
0
];
dely
=
ytmp
-
x
[
j
][
1
];
delz
=
ztmp
-
x
[
j
][
2
];
rsq
=
delx
*
delx
+
dely
*
dely
+
delz
*
delz
;
delx0
=
xtmp0
-
x0
[
j
][
0
];
dely0
=
ytmp0
-
x0
[
j
][
1
];
delz0
=
ztmp0
-
x0
[
j
][
2
];
if
(
periodic
)
domain
->
minimum_image
(
delx0
,
dely0
,
delz0
);
rsq0
=
delx0
*
delx0
+
dely0
*
dely0
+
delz0
*
delz0
;
jtype
=
type
[
j
];
r
=
sqrt
(
rsq
);
// short-range interaction distance based on initial particle position
// 0.9 and 1.35 are constants
d_ij
=
MIN
(
0.9
*
sqrt
(
rsq0
),
1.35
*
lc
);
// short-range contact forces
// 15 is constant taken from the EMU Theory Manual
// Silling, 12 May 2005, p 18
if
(
r
<
d_ij
)
{
dr
=
r
-
d_ij
;
// kshort based upon short-range force constant
// of the bond-based theory used in PMB model
double
kshort
=
(
15.0
*
18.0
*
bulkmodulus
[
itype
][
itype
])
/
(
3.141592653589793
*
cutsq
[
itype
][
jtype
]
*
cutsq
[
itype
][
jtype
]);
rk
=
(
kshort
*
vfrac
[
j
])
*
(
dr
/
cut
[
itype
][
jtype
]);
if
(
r
>
0.0
)
fpair
=
-
(
rk
/
r
);
else
fpair
=
0.0
;
f
[
i
][
0
]
+=
delx
*
fpair
;
f
[
i
][
1
]
+=
dely
*
fpair
;
f
[
i
][
2
]
+=
delz
*
fpair
;
if
(
newton_pair
||
j
<
nlocal
)
{
f
[
j
][
0
]
-=
delx
*
fpair
;
f
[
j
][
1
]
-=
dely
*
fpair
;
f
[
j
][
2
]
-=
delz
*
fpair
;
}
if
(
eflag
)
evdwl
=
0.5
*
rk
*
dr
;
if
(
evflag
)
ev_tally
(
i
,
j
,
nlocal
,
newton_pair
,
evdwl
,
0.0
,
fpair
*
vfrac
[
i
],
delx
,
dely
,
delz
);
}
}
}
// grow bond forces array if necessary
if
(
atom
->
nmax
>
nmax
)
{
memory
->
destroy
(
s0_new
);
memory
->
destroy
(
theta
);
nmax
=
atom
->
nmax
;
memory
->
create
(
s0_new
,
nmax
,
"pair:s0_new"
);
memory
->
create
(
theta
,
nmax
,
"pair:theta"
);
}
// Compute the dilatation on each particle
compute_dilatation
();
// communicate dilatation (theta) of each particle
comm
->
forward_comm_pair
(
this
);
// communicate wighted volume (wvolume) upon every reneighbor
if
(
neighbor
->
ago
==
0
)
comm
->
forward_comm_fix
(
modify
->
fix
[
ifix_peri
]);
// Volume-dependent part of the energy
if
(
eflag
)
{
for
(
i
=
0
;
i
<
nlocal
;
i
++
)
{
itype
=
type
[
i
];
if
(
eflag_global
)
eng_vdwl
+=
0.5
*
bulkmodulus
[
itype
][
itype
]
*
(
theta
[
i
]
*
theta
[
i
]);
if
(
eflag_atom
)
eatom
[
i
]
+=
0.5
*
bulkmodulus
[
itype
][
itype
]
*
(
theta
[
i
]
*
theta
[
i
]);
}
}
// loop over my particles and their partners
// partner list contains all bond partners, so I-J appears twice
// if bond already broken, skip this partner
// first = true if this is first neighbor of particle i
bool
first
;
double
omega_minus
,
omega_plus
;
for
(
i
=
0
;
i
<
nlocal
;
i
++
)
{
xtmp
=
x
[
i
][
0
];
ytmp
=
x
[
i
][
1
];
ztmp
=
x
[
i
][
2
];
xtmp0
=
x0
[
i
][
0
];
ytmp0
=
x0
[
i
][
1
];
ztmp0
=
x0
[
i
][
2
];
itype
=
type
[
i
];
jnum
=
npartner
[
i
];
first
=
true
;
for
(
jj
=
0
;
jj
<
jnum
;
jj
++
)
{
if
(
partner
[
i
][
jj
]
==
0
)
continue
;
j
=
atom
->
map
(
partner
[
i
][
jj
]);
// check if lost a partner without first breaking bond
if
(
j
<
0
)
{
partner
[
i
][
jj
]
=
0
;
continue
;
}
// compute force density, add to PD equation of motion
delx
=
xtmp
-
x
[
j
][
0
];
dely
=
ytmp
-
x
[
j
][
1
];
delz
=
ztmp
-
x
[
j
][
2
];
if
(
periodic
)
domain
->
minimum_image
(
delx
,
dely
,
delz
);
rsq
=
delx
*
delx
+
dely
*
dely
+
delz
*
delz
;
delx0
=
xtmp0
-
x0
[
j
][
0
];
dely0
=
ytmp0
-
x0
[
j
][
1
];
delz0
=
ztmp0
-
x0
[
j
][
2
];
if
(
periodic
)
domain
->
minimum_image
(
delx0
,
dely0
,
delz0
);
jtype
=
type
[
j
];
delta
=
cut
[
itype
][
jtype
];
r
=
sqrt
(
rsq
);
dr
=
r
-
r0
[
i
][
jj
];
// avoid roundoff errors
if
(
fabs
(
dr
)
<
2.2204e-016
)
dr
=
0.0
;
// scale vfrac[j] if particle j near the horizon
if
((
fabs
(
r0
[
i
][
jj
]
-
delta
))
<=
half_lc
)
vfrac_scale
=
(
-
1.0
/
(
2
*
half_lc
))
*
(
r0
[
i
][
jj
])
+
(
1.0
+
((
delta
-
half_lc
)
/
(
2
*
half_lc
)
)
);
else
vfrac_scale
=
1.0
;
omega_plus
=
influence_function
(
-
1.0
*
delx0
,
-
1.0
*
dely0
,
-
1.0
*
delz0
);
omega_minus
=
influence_function
(
delx0
,
dely0
,
delz0
);
rk
=
(
(
3.0
*
bulkmodulus
[
itype
][
itype
])
-
(
5.0
*
shearmodulus
[
itype
][
itype
])
)
*
vfrac
[
j
]
*
vfrac_scale
*
(
(
omega_plus
*
theta
[
i
]
/
wvolume
[
i
])
+
(
omega_minus
*
theta
[
j
]
/
wvolume
[
j
]
)
)
*
r0
[
i
][
jj
];
rk
+=
15.0
*
(
shearmodulus
[
itype
][
itype
]
*
vfrac
[
j
]
*
vfrac_scale
)
*
(
(
omega_plus
/
wvolume
[
i
])
+
(
omega_minus
/
wvolume
[
j
])
)
*
dr
;
if
(
r
>
0.0
)
fbond
=
-
(
rk
/
r
);
else
fbond
=
0.0
;
f
[
i
][
0
]
+=
delx
*
fbond
;
f
[
i
][
1
]
+=
dely
*
fbond
;
f
[
i
][
2
]
+=
delz
*
fbond
;
// since I-J is double counted, set newton off & use 1/2 factor and I,I
double
deviatoric_extension
=
dr
-
(
theta
[
i
]
*
r0
[
i
][
jj
]
/
3.0
);
if
(
eflag
)
evdwl
=
0.5
*
15
*
(
shearmodulus
[
itype
][
itype
]
/
wvolume
[
i
])
*
omega_plus
*
(
deviatoric_extension
*
deviatoric_extension
)
*
vfrac
[
j
]
*
vfrac_scale
;
if
(
evflag
)
ev_tally
(
i
,
i
,
nlocal
,
0
,
0.5
*
evdwl
,
0.0
,
0.5
*
fbond
*
vfrac
[
i
],
delx
,
dely
,
delz
);
// find stretch in bond I-J and break if necessary
// use s0 from previous timestep
stretch
=
dr
/
r0
[
i
][
jj
];
if
(
stretch
>
MIN
(
s0
[
i
],
s0
[
j
]))
partner
[
i
][
jj
]
=
0
;
// update s0 for next timestep
if
(
first
)
s0_new
[
i
]
=
s00
[
itype
][
jtype
]
-
(
alpha
[
itype
][
jtype
]
*
stretch
);
else
s0_new
[
i
]
=
MAX
(
s0_new
[
i
],
s00
[
itype
][
jtype
]
-
(
alpha
[
itype
][
jtype
]
*
stretch
));
first
=
false
;
}
}
// store new s0
for
(
i
=
0
;
i
<
nlocal
;
i
++
)
s0
[
i
]
=
s0_new
[
i
];
}
/* ----------------------------------------------------------------------
allocate all arrays
------------------------------------------------------------------------- */
void
PairPeriLPS
::
allocate
()
{
allocated
=
1
;
int
n
=
atom
->
ntypes
;
memory
->
create
(
setflag
,
n
+
1
,
n
+
1
,
"pair:setflag"
);
for
(
int
i
=
1
;
i
<=
n
;
i
++
)
for
(
int
j
=
i
;
j
<=
n
;
j
++
)
setflag
[
i
][
j
]
=
0
;
memory
->
create
(
cutsq
,
n
+
1
,
n
+
1
,
"pair:cutsq"
);
memory
->
create
(
bulkmodulus
,
n
+
1
,
n
+
1
,
"pair:bulkmodulus"
);
memory
->
create
(
shearmodulus
,
n
+
1
,
n
+
1
,
"pair:shearmodulus"
);
memory
->
create
(
s00
,
n
+
1
,
n
+
1
,
"pair:s00"
);
memory
->
create
(
alpha
,
n
+
1
,
n
+
1
,
"pair:alpha"
);
memory
->
create
(
cut
,
n
+
1
,
n
+
1
,
"pair:cut"
);
}
/* ----------------------------------------------------------------------
global settings
------------------------------------------------------------------------- */
void
PairPeriLPS
::
settings
(
int
narg
,
char
**
arg
)
{
if
(
narg
)
error
->
all
(
FLERR
,
"Illegal pair_style command"
);
}
/* ----------------------------------------------------------------------
set coeffs for one or more type pairs
------------------------------------------------------------------------- */
void
PairPeriLPS
::
coeff
(
int
narg
,
char
**
arg
)
{
if
(
narg
!=
7
)
error
->
all
(
FLERR
,
"Incorrect args for pair coefficients"
);
if
(
!
allocated
)
allocate
();
int
ilo
,
ihi
,
jlo
,
jhi
;
force
->
bounds
(
arg
[
0
],
atom
->
ntypes
,
ilo
,
ihi
);
force
->
bounds
(
arg
[
1
],
atom
->
ntypes
,
jlo
,
jhi
);
double
bulkmodulus_one
=
force
->
numeric
(
FLERR
,
arg
[
2
]);
double
shearmodulus_one
=
force
->
numeric
(
FLERR
,
arg
[
3
]);
double
cut_one
=
force
->
numeric
(
FLERR
,
arg
[
4
]);
double
s00_one
=
force
->
numeric
(
FLERR
,
arg
[
5
]);
double
alpha_one
=
force
->
numeric
(
FLERR
,
arg
[
6
]);
int
count
=
0
;
for
(
int
i
=
ilo
;
i
<=
ihi
;
i
++
)
{
for
(
int
j
=
MAX
(
jlo
,
i
);
j
<=
jhi
;
j
++
)
{
bulkmodulus
[
i
][
j
]
=
bulkmodulus_one
;
shearmodulus
[
i
][
j
]
=
shearmodulus_one
;
cut
[
i
][
j
]
=
cut_one
;
s00
[
i
][
j
]
=
s00_one
;
alpha
[
i
][
j
]
=
alpha_one
;
setflag
[
i
][
j
]
=
1
;
count
++
;
}
}
if
(
count
==
0
)
error
->
all
(
FLERR
,
"Incorrect args for pair coefficients"
);
}
/* ----------------------------------------------------------------------
init for one type pair i,j and corresponding j,i
------------------------------------------------------------------------- */
double
PairPeriLPS
::
init_one
(
int
i
,
int
j
)
{
if
(
setflag
[
i
][
j
]
==
0
)
error
->
all
(
FLERR
,
"All pair coeffs are not set"
);
bulkmodulus
[
j
][
i
]
=
bulkmodulus
[
i
][
j
];
shearmodulus
[
j
][
i
]
=
shearmodulus
[
i
][
j
];
s00
[
j
][
i
]
=
s00
[
i
][
j
];
alpha
[
j
][
i
]
=
alpha
[
i
][
j
];
cut
[
j
][
i
]
=
cut
[
i
][
j
];
return
cut
[
i
][
j
];
}
/* ----------------------------------------------------------------------
init specific to this pair style
------------------------------------------------------------------------- */
void
PairPeriLPS
::
init_style
()
{
// error checks
if
(
!
atom
->
peri_flag
)
error
->
all
(
FLERR
,
"Pair style peri requires atom style peri"
);
if
(
atom
->
map_style
==
0
)
error
->
all
(
FLERR
,
"Pair peri requires an atom map, see atom_modify"
);
if
(
domain
->
lattice
->
xlattice
!=
domain
->
lattice
->
ylattice
||
domain
->
lattice
->
xlattice
!=
domain
->
lattice
->
zlattice
||
domain
->
lattice
->
ylattice
!=
domain
->
lattice
->
zlattice
)
error
->
all
(
FLERR
,
"Pair peri lattice is not identical in x, y, and z"
);
// if first init, create Fix needed for storing fixed neighbors
if
(
ifix_peri
==
-
1
)
{
char
**
fixarg
=
new
char
*
[
3
];
fixarg
[
0
]
=
(
char
*
)
"PERI_NEIGH"
;
fixarg
[
1
]
=
(
char
*
)
"all"
;
fixarg
[
2
]
=
(
char
*
)
"PERI_NEIGH"
;
modify
->
add_fix
(
3
,
fixarg
);
delete
[]
fixarg
;
}
// find associated PERI_NEIGH fix that must exist
// could have changed locations in fix list since created
for
(
int
i
=
0
;
i
<
modify
->
nfix
;
i
++
)
if
(
strcmp
(
modify
->
fix
[
i
]
->
style
,
"PERI_NEIGH"
)
==
0
)
ifix_peri
=
i
;
if
(
ifix_peri
==
-
1
)
error
->
all
(
FLERR
,
"Fix peri neigh does not exist"
);
neighbor
->
request
(
this
);
}
/* ----------------------------------------------------------------------
proc 0 writes to restart file
------------------------------------------------------------------------- */
void
PairPeriLPS
::
write_restart
(
FILE
*
fp
)
{
int
i
,
j
;
for
(
i
=
1
;
i
<=
atom
->
ntypes
;
i
++
)
for
(
j
=
i
;
j
<=
atom
->
ntypes
;
j
++
)
{
fwrite
(
&
setflag
[
i
][
j
],
sizeof
(
int
),
1
,
fp
);
if
(
setflag
[
i
][
j
])
{
fwrite
(
&
bulkmodulus
[
i
][
j
],
sizeof
(
double
),
1
,
fp
);
fwrite
(
&
shearmodulus
[
i
][
j
],
sizeof
(
double
),
1
,
fp
);
fwrite
(
&
s00
[
i
][
j
],
sizeof
(
double
),
1
,
fp
);
fwrite
(
&
alpha
[
i
][
j
],
sizeof
(
double
),
1
,
fp
);
fwrite
(
&
cut
[
i
][
j
],
sizeof
(
double
),
1
,
fp
);
}
}
}
/* ----------------------------------------------------------------------
proc 0 reads from restart file, bcasts
------------------------------------------------------------------------- */
void
PairPeriLPS
::
read_restart
(
FILE
*
fp
)
{
allocate
();
int
i
,
j
;
int
me
=
comm
->
me
;
for
(
i
=
1
;
i
<=
atom
->
ntypes
;
i
++
)
for
(
j
=
i
;
j
<=
atom
->
ntypes
;
j
++
)
{
if
(
me
==
0
)
fread
(
&
setflag
[
i
][
j
],
sizeof
(
int
),
1
,
fp
);
MPI_Bcast
(
&
setflag
[
i
][
j
],
1
,
MPI_INT
,
0
,
world
);
if
(
setflag
[
i
][
j
])
{
if
(
me
==
0
)
{
fread
(
&
bulkmodulus
[
i
][
j
],
sizeof
(
double
),
1
,
fp
);
fread
(
&
shearmodulus
[
i
][
j
],
sizeof
(
double
),
1
,
fp
);
fread
(
&
s00
[
i
][
j
],
sizeof
(
double
),
1
,
fp
);
fread
(
&
alpha
[
i
][
j
],
sizeof
(
double
),
1
,
fp
);
fread
(
&
cut
[
i
][
j
],
sizeof
(
double
),
1
,
fp
);
}
MPI_Bcast
(
&
bulkmodulus
[
i
][
j
],
1
,
MPI_DOUBLE
,
0
,
world
);
MPI_Bcast
(
&
shearmodulus
[
i
][
j
],
1
,
MPI_DOUBLE
,
0
,
world
);
MPI_Bcast
(
&
s00
[
i
][
j
],
1
,
MPI_DOUBLE
,
0
,
world
);
MPI_Bcast
(
&
alpha
[
i
][
j
],
1
,
MPI_DOUBLE
,
0
,
world
);
MPI_Bcast
(
&
cut
[
i
][
j
],
1
,
MPI_DOUBLE
,
0
,
world
);
}
}
}
/* ----------------------------------------------------------------------
memory usage of local atom-based arrays
------------------------------------------------------------------------- */
double
PairPeriLPS
::
memory_usage
()
{
double
bytes
=
2
*
nmax
*
sizeof
(
double
);
return
bytes
;
}
/* ----------------------------------------------------------------------
influence function definition
------------------------------------------------------------------------- */
double
PairPeriLPS
::
influence_function
(
double
xi_x
,
double
xi_y
,
double
xi_z
)
{
double
r
=
sqrt
(
xi_x
*
xi_x
+
xi_y
*
xi_y
+
xi_z
*
xi_z
);
double
omega
;
if
(
fabs
(
r
)
<
2.2204e-016
)
error
->
one
(
FLERR
,
"Divide by 0 in influence function of pair peri/lps"
);
omega
=
1.0
/
r
;
return
omega
;
}
/* ---------------------------------------------------------------------- */
void
PairPeriLPS
::
compute_dilatation
()
{
int
i
,
j
,
jj
,
jnum
,
itype
,
jtype
;
double
xtmp
,
ytmp
,
ztmp
,
delx
,
dely
,
delz
;
double
xtmp0
,
ytmp0
,
ztmp0
,
delx0
,
dely0
,
delz0
;
double
rsq
,
r
,
dr
;
double
delta
;
double
**
x
=
atom
->
x
;
int
*
type
=
atom
->
type
;
double
**
x0
=
atom
->
x0
;
int
nlocal
=
atom
->
nlocal
;
double
*
vfrac
=
atom
->
vfrac
;
double
vfrac_scale
=
1.0
;
double
lc
=
domain
->
lattice
->
xlattice
;
double
half_lc
=
0.5
*
lc
;
double
**
r0
=
((
FixPeriNeigh
*
)
modify
->
fix
[
ifix_peri
])
->
r0
;
tagint
**
partner
=
((
FixPeriNeigh
*
)
modify
->
fix
[
ifix_peri
])
->
partner
;
int
*
npartner
=
((
FixPeriNeigh
*
)
modify
->
fix
[
ifix_peri
])
->
npartner
;
double
*
wvolume
=
((
FixPeriNeigh
*
)
modify
->
fix
[
ifix_peri
])
->
wvolume
;
int
periodic
=
domain
->
xperiodic
||
domain
->
yperiodic
||
domain
->
zperiodic
;
// compute the dilatation theta
for
(
i
=
0
;
i
<
nlocal
;
i
++
)
{
xtmp
=
x
[
i
][
0
];
ytmp
=
x
[
i
][
1
];
ztmp
=
x
[
i
][
2
];
xtmp0
=
x0
[
i
][
0
];
ytmp0
=
x0
[
i
][
1
];
ztmp0
=
x0
[
i
][
2
];
jnum
=
npartner
[
i
];
theta
[
i
]
=
0.0
;
itype
=
type
[
i
];
for
(
jj
=
0
;
jj
<
jnum
;
jj
++
)
{
// if bond already broken, skip this partner
if
(
partner
[
i
][
jj
]
==
0
)
continue
;
// Look up local index of this partner particle
j
=
atom
->
map
(
partner
[
i
][
jj
]);
// Skip if particle is "lost"
if
(
j
<
0
)
continue
;
// Compute force density and add to PD equation of motion
delx
=
xtmp
-
x
[
j
][
0
];
dely
=
ytmp
-
x
[
j
][
1
];
delz
=
ztmp
-
x
[
j
][
2
];
if
(
periodic
)
domain
->
minimum_image
(
delx
,
dely
,
delz
);
rsq
=
delx
*
delx
+
dely
*
dely
+
delz
*
delz
;
delx0
=
xtmp0
-
x0
[
j
][
0
];
dely0
=
ytmp0
-
x0
[
j
][
1
];
delz0
=
ztmp0
-
x0
[
j
][
2
];
if
(
periodic
)
domain
->
minimum_image
(
delx0
,
dely0
,
delz0
);
r
=
sqrt
(
rsq
);
dr
=
r
-
r0
[
i
][
jj
];
if
(
fabs
(
dr
)
<
2.2204e-016
)
dr
=
0.0
;
jtype
=
type
[
j
];
delta
=
cut
[
itype
][
jtype
];
// scale vfrac[j] if particle j near the horizon
if
((
fabs
(
r0
[
i
][
jj
]
-
delta
))
<=
half_lc
)
vfrac_scale
=
(
-
1.0
/
(
2
*
half_lc
))
*
(
r0
[
i
][
jj
])
+
(
1.0
+
((
delta
-
half_lc
)
/
(
2
*
half_lc
)
)
);
else
vfrac_scale
=
1.0
;
theta
[
i
]
+=
influence_function
(
delx0
,
dely0
,
delz0
)
*
r0
[
i
][
jj
]
*
dr
*
vfrac
[
j
]
*
vfrac_scale
;
}
// if wvolume[i] is zero, then particle i has no bonds
// therefore, the dilatation is set to
if
(
wvolume
[
i
]
!=
0.0
)
theta
[
i
]
=
(
3.0
/
wvolume
[
i
])
*
theta
[
i
];
else
theta
[
i
]
=
0
;
}
}
/* ----------------------------------------------------------------------
communication routines
---------------------------------------------------------------------- */
int
PairPeriLPS
::
pack_forward_comm
(
int
n
,
int
*
list
,
double
*
buf
,
int
pbc_flag
,
int
*
pbc
)
{
int
i
,
j
,
m
;
m
=
0
;
for
(
i
=
0
;
i
<
n
;
i
++
)
{
j
=
list
[
i
];
buf
[
m
++
]
=
theta
[
j
];
}
return
m
;
}
/* ---------------------------------------------------------------------- */
void
PairPeriLPS
::
unpack_forward_comm
(
int
n
,
int
first
,
double
*
buf
)
{
int
i
,
m
,
last
;
m
=
0
;
last
=
first
+
n
;
for
(
i
=
first
;
i
<
last
;
i
++
)
{
theta
[
i
]
=
buf
[
m
++
];
}
}
Event Timeline
Log In to Comment