git-svn-id: svn://svn.icms.temple.edu/lammps-ro/trunk@255 f3b2605a-c512-4ea7-a41b-209d697bcdaa
This commit is contained in:
sjplimp
210
src/compute_pressure.cpp
Normal file
210
src/compute_pressure.cpp
Normal file
@ -0,0 +1,210 @@
|
||||
/* ----------------------------------------------------------------------
|
||||
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.
|
||||
------------------------------------------------------------------------- */
|
||||
|
||||
#include "mpi.h"
|
||||
#include "string.h"
|
||||
#include "stdlib.h"
|
||||
#include "compute_pressure.h"
|
||||
#include "atom.h"
|
||||
#include "domain.h"
|
||||
#include "modify.h"
|
||||
#include "fix.h"
|
||||
#include "force.h"
|
||||
#include "pair.h"
|
||||
#include "bond.h"
|
||||
#include "angle.h"
|
||||
#include "dihedral.h"
|
||||
#include "improper.h"
|
||||
#include "kspace.h"
|
||||
#include "error.h"
|
||||
|
||||
using namespace LAMMPS_NS;
|
||||
|
||||
/* ---------------------------------------------------------------------- */
|
||||
|
||||
ComputePressure::ComputePressure(LAMMPS *lmp, int narg, char **arg) :
|
||||
Compute(lmp, narg, arg)
|
||||
{
|
||||
if (narg != 4) error->all("Illegal compute pressure command");
|
||||
|
||||
if (igroup) error->all("Compute pressure must use group all");
|
||||
|
||||
// store temperature ID used by pressure computation
|
||||
// insure it is valid for temperature computation
|
||||
|
||||
int n = strlen(arg[3]) + 1;
|
||||
id_pre = new char[n];
|
||||
strcpy(id_pre,arg[3]);
|
||||
|
||||
int icompute = modify->find_compute(id_pre);
|
||||
|
||||
if (icompute < 0) error->all("Could not find compute pressure temp ID");
|
||||
if (modify->compute[icompute]->tempflag == 0)
|
||||
error->all("Compute pressure temp ID does not compute temperature");
|
||||
|
||||
scalar_flag = vector_flag = 1;
|
||||
size_vector = 6;
|
||||
extensive = 0;
|
||||
pressflag = 1;
|
||||
|
||||
vector = new double[6];
|
||||
}
|
||||
|
||||
/* ---------------------------------------------------------------------- */
|
||||
|
||||
ComputePressure::~ComputePressure()
|
||||
{
|
||||
delete [] id_pre;
|
||||
delete [] vector;
|
||||
}
|
||||
|
||||
/* ---------------------------------------------------------------------- */
|
||||
|
||||
void ComputePressure::init()
|
||||
{
|
||||
boltz = force->boltz;
|
||||
nktv2p = force->nktv2p;
|
||||
|
||||
// set temperature used by pressure
|
||||
|
||||
int icompute = modify->find_compute(id_pre);
|
||||
if (icompute < 0) error->all("Could not find compute pressure temp ID");
|
||||
temperature = modify->compute[icompute];
|
||||
|
||||
// set flags/ptrs for all contributions to virial
|
||||
|
||||
pairflag = bondflag = angleflag = dihedralflag = improperflag = 0;
|
||||
kspaceflag = 0;
|
||||
shakeflag = bodyflag = rigidflag = poemsflag = 0;
|
||||
|
||||
if (force->pair) {
|
||||
pairflag = 1;
|
||||
pair_virial = force->pair->virial;
|
||||
}
|
||||
if (atom->molecular) {
|
||||
if (force->bond) {
|
||||
bondflag = 1;
|
||||
bond_virial = force->bond->virial;
|
||||
}
|
||||
if (force->angle) {
|
||||
angleflag = 1;
|
||||
angle_virial = force->angle->virial;
|
||||
}
|
||||
if (force->dihedral) {
|
||||
dihedralflag = 1;
|
||||
dihedral_virial = force->dihedral->virial;
|
||||
}
|
||||
if (force->improper) {
|
||||
improperflag = 1;
|
||||
improper_virial = force->improper->virial;
|
||||
}
|
||||
}
|
||||
|
||||
if (force->kspace) {
|
||||
kspaceflag = 1;
|
||||
kspace_virial = force->kspace->virial;
|
||||
}
|
||||
|
||||
for (int i = 0; i < modify->nfix; i++) {
|
||||
if (strcmp(modify->fix[i]->style,"shake") == 0) {
|
||||
shakeflag = 1;
|
||||
shake_virial = modify->fix[i]->virial;
|
||||
}
|
||||
if (strcmp(modify->fix[i]->style,"rigid") == 0 ||
|
||||
strcmp(modify->fix[i]->style,"poems") == 0) {
|
||||
bodyflag = 1;
|
||||
if (strcmp(modify->fix[i]->style,"rigid") == 0) {
|
||||
rigidflag = 1;
|
||||
rigid_virial = modify->fix[i]->virial;
|
||||
} else {
|
||||
poemsflag = 1;
|
||||
poems_virial = modify->fix[i]->virial;
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/* ----------------------------------------------------------------------
|
||||
compute total pressure, averaged over Pxx, Pyy, Pzz
|
||||
assume temperature has already been computed
|
||||
------------------------------------------------------------------------- */
|
||||
|
||||
double ComputePressure::compute_scalar()
|
||||
{
|
||||
inv_volume = 1.0 / (domain->xprd * domain->yprd * domain->zprd);
|
||||
virial_compute(3);
|
||||
scalar = (temperature->dof * boltz * temperature->scalar +
|
||||
virial[0] + virial[1] + virial[2]) / 3.0 * inv_volume * nktv2p;
|
||||
return scalar;
|
||||
}
|
||||
|
||||
/* ----------------------------------------------------------------------
|
||||
compute pressure tensor
|
||||
assume KE tensor has already been computed
|
||||
------------------------------------------------------------------------- */
|
||||
|
||||
void ComputePressure::compute_vector()
|
||||
{
|
||||
inv_volume = 1.0 / (domain->xprd * domain->yprd * domain->zprd);
|
||||
virial_compute(6);
|
||||
double *ke_tensor = temperature->vector;
|
||||
for (int i = 0; i < 6; i++)
|
||||
vector[i] = (ke_tensor[i] + virial[i]) * inv_volume * nktv2p;
|
||||
}
|
||||
|
||||
/* ---------------------------------------------------------------------- */
|
||||
|
||||
void ComputePressure::virial_compute(int n)
|
||||
{
|
||||
int i;
|
||||
double v[6];
|
||||
|
||||
for (i = 0; i < n; i++) v[i] = 0.0;
|
||||
|
||||
// sum contributions to virial from various forces and fixes
|
||||
|
||||
if (pairflag)
|
||||
for (i = 0; i < n; i++) v[i] += pair_virial[i];
|
||||
|
||||
if (atom->molecular) {
|
||||
if (bondflag)
|
||||
for (i = 0; i < n; i++) v[i] += bond_virial[i];
|
||||
if (angleflag)
|
||||
for (i = 0; i < n; i++) v[i] += angle_virial[i];
|
||||
if (dihedralflag)
|
||||
for (i = 0; i < n; i++) v[i] += dihedral_virial[i];
|
||||
if (improperflag)
|
||||
for (i = 0; i < n; i++) v[i] += improper_virial[i];
|
||||
if (shakeflag)
|
||||
for (i = 0; i < n; i++) v[i] += shake_virial[i];
|
||||
}
|
||||
|
||||
if (bodyflag) {
|
||||
if (rigidflag) for (i = 0; i < n; i++) v[i] += rigid_virial[i];
|
||||
if (poemsflag) for (i = 0; i < n; i++) v[i] += poems_virial[i];
|
||||
}
|
||||
|
||||
// sum virial across procs
|
||||
|
||||
MPI_Allreduce(v,virial,n,MPI_DOUBLE,MPI_SUM,world);
|
||||
|
||||
// KSpace virial contribution is already summed across procs
|
||||
|
||||
if (force->kspace)
|
||||
for (i = 0; i < n; i++) virial[i] += kspace_virial[i];
|
||||
|
||||
// LJ long-range tail correction
|
||||
|
||||
if (force->pair && force->pair->tail_flag)
|
||||
for (i = 0; i < n; i++) virial[i] += force->pair->ptail * inv_volume;
|
||||
}
|
||||
Reference in New Issue
Block a user