Page Menu
Home
c4science
Search
Configure Global Search
Log In
Files
F86998323
fix_nphug_omp.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
Wed, Oct 9, 21:44
Size
10 KB
Mime Type
text/x-c
Expires
Fri, Oct 11, 21:44 (1 d, 23 h)
Engine
blob
Format
Raw Data
Handle
21520166
Attached To
rLAMMPS lammps
fix_nphug_omp.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.
------------------------------------------------------------------------- */
#include <string.h>
#include <stdlib.h>
#include "fix_nphug_omp.h"
#include "modify.h"
#include "error.h"
#include "update.h"
#include "compute.h"
#include "force.h"
#include "domain.h"
#include "group.h"
#include <math.h>
#include "memory.h"
#include "comm.h"
#include <math.h>
using namespace LAMMPS_NS;
using namespace FixConst;
enum{ISO,ANISO,TRICLINIC}; // same as fix_nh.cpp
/* ---------------------------------------------------------------------- */
FixNPHugOMP::FixNPHugOMP(LAMMPS *lmp, int narg, char **arg) :
FixNHOMP(lmp, narg, arg)
{
// Prevent masses from being updated every timestep
eta_mass_flag = 0;
omega_mass_flag = 0;
etap_mass_flag = 0;
// extend vector of base-class computes
size_vector += 3;
// turn off deviatoric flag and remove strain energy from vector
deviatoric_flag = 0;
size_vector -= 1;
// use initial state as reference state
v0_set = p0_set = e0_set = 0;
// check pressure settings
if (p_start[0] != p_stop[0] ||
p_start[1] != p_stop[1] ||
p_start[2] != p_stop[2])
error->all(FLERR,"Pstart and Pstop must have the same value");
// uniaxial = 0 means hydrostatic compression
// uniaxial = 1 means uniaxial compression
// in x, y, or z (idir = 0, 1, or 2)
// isotropic hydrostatic compression
if (pstyle == ISO) {
uniaxial = 0;
// anisotropic compression
} else if (pstyle == ANISO) {
// anisotropic hydrostatic compression
if (p_start[0] == p_start[1] &&
p_start[0] == p_start[2] )
uniaxial = 0;
// uniaxial compression
else if (p_flag[0] == 1 && p_flag[1] == 0
&& p_flag[2] == 0) {
uniaxial = 1;
idir = 0;
} else if (p_flag[0] == 0 && p_flag[1] == 1
&& p_flag[2] == 0) {
uniaxial = 1;
idir = 1;
} else if (p_flag[0] == 0 && p_flag[1] == 0
&& p_flag[2] == 1) {
uniaxial = 1;
idir = 2;
} else error->all(FLERR,"Specified target stress must be uniaxial or hydrostatic");
// triclinic hydrostatic compression
} else if (pstyle == TRICLINIC) {
if (p_start[0] == p_start[1] &&
p_start[0] == p_start[2] &&
p_start[3] == 0.0 &&
p_start[4] == 0.0 &&
p_start[5] == 0.0 )
uniaxial = 0;
else error->all(FLERR,"For triclinic deformation, specified target stress must be hydrostatic");
}
if (!tstat_flag)
error->all(FLERR,"Temperature control must be used with fix nphug/omp");
if (!pstat_flag)
error->all(FLERR,"Pressure control must be used with fix nphug/omp");
// create a new compute temp style
// id = fix-ID + temp
// compute group = all since pressure is always global (group all)
// and thus its KE/temperature contribution should use group all
int n = strlen(id) + 6;
id_temp = new char[n];
strcpy(id_temp,id);
strcat(id_temp,"_temp");
char **newarg = new char*[3];
newarg[0] = id_temp;
newarg[1] = (char *) "all";
newarg[2] = (char *) "temp";
modify->add_compute(3,newarg);
delete [] newarg;
tcomputeflag = 1;
// create a new compute pressure style
// id = fix-ID + press, compute group = all
// pass id_temp as 4th arg to pressure constructor
n = strlen(id) + 7;
id_press = new char[n];
strcpy(id_press,id);
strcat(id_press,"_press");
newarg = new char*[4];
newarg[0] = id_press;
newarg[1] = (char *) "all";
newarg[2] = (char *) "pressure";
newarg[3] = id_temp;
modify->add_compute(4,newarg);
delete [] newarg;
pcomputeflag = 1;
// create a new compute potential energy compute
n = strlen(id) + 3;
id_pe = new char[n];
strcpy(id_pe,id);
strcat(id_pe,"_pe");
newarg = new char*[3];
newarg[0] = id_pe;
newarg[1] = (char*)"all";
newarg[2] = (char*)"pe";
modify->add_compute(3,newarg);
delete [] newarg;
peflag = 1;
}
/* ---------------------------------------------------------------------- */
FixNPHugOMP::~FixNPHugOMP()
{
// temp and press computes handled by base class
// delete pe compute
if (peflag) modify->delete_compute(id_pe);
delete [] id_pe;
}
/* ---------------------------------------------------------------------- */
void FixNPHugOMP::init()
{
// Call base class init()
FixNHOMP::init();
// set pe ptr
int icompute = modify->find_compute(id_pe);
if (icompute < 0)
error->all(FLERR,"Potential energy ID for fix nvt/nph/npt does not exist");
pe = modify->compute[icompute];
}
/* ----------------------------------------------------------------------
compute initial state before integrator starts
------------------------------------------------------------------------- */
void FixNPHugOMP::setup(int vflag)
{
FixNHOMP::setup(vflag);
if ( v0_set == 0 ) {
v0 = compute_vol();
v0_set = 1;
}
if ( p0_set == 0 ) {
p0_set = 1;
if (uniaxial == 1)
p0 = p_current[idir];
else
p0 = (p_current[0]+p_current[1]+p_current[2])/3.0;
}
if ( e0_set == 0 ) {
e0 = compute_etotal();
e0_set = 1;
}
double masstot = group->mass(igroup);
rho0 = nktv2p*force->mvv2e*masstot/v0;
t_target = 0.01;
pe->addstep(update->ntimestep+1);
}
/* ----------------------------------------------------------------------
compute target temperature and kinetic energy
-----------------------------------------------------------------------*/
void FixNPHugOMP::compute_temp_target()
{
t_target = t_current + compute_hugoniot();
ke_target = tdof * boltz * t_target;
pe->addstep(update->ntimestep+1);
}
/* ---------------------------------------------------------------------- */
double FixNPHugOMP::compute_etotal()
{
double epot,ekin,etot;
epot = pe->compute_scalar();
if (thermo_energy) epot -= compute_scalar();
ekin = temperature->compute_scalar();
ekin *= 0.5 * tdof * force->boltz;
etot = epot+ekin;
return etot;
}
/* ---------------------------------------------------------------------- */
double FixNPHugOMP::compute_vol()
{
if (domain->dimension == 3)
return domain->xprd * domain->yprd * domain->zprd;
else
return domain->xprd * domain->yprd;
}
/* ----------------------------------------------------------------------
Computes the deviation of the current point
from the Hugoniot in temperature units.
------------------------------------------------------------------------- */
double FixNPHugOMP::compute_hugoniot()
{
double v,e,p;
double dhugo;
e = compute_etotal();
temperature->compute_vector();
if (uniaxial == 1) {
pressure->compute_vector();
p = pressure->vector[idir];
} else
p = pressure->compute_scalar();
v = compute_vol();
dhugo = (0.5 * (p + p0 ) * ( v0 - v)) /
force->nktv2p + e0 - e;
dhugo /= tdof * boltz;
return dhugo;
}
/* ----------------------------------------------------------------------
Compute shock velocity is distance/time units
------------------------------------------------------------------------- */
double FixNPHugOMP::compute_us()
{
double v,p;
double eps,us;
temperature->compute_vector();
if (uniaxial == 1) {
pressure->compute_vector();
p = pressure->vector[idir];
} else
p = pressure->compute_scalar();
v = compute_vol();
// Us^2 = (p-p0)/(rho0*eps)
eps = 1.0 - v/v0;
if (eps < 1.0e-10) us = 0.0;
else if (p < p0) us = 0.0;
else us = sqrt((p-p0)/(rho0*eps));
return us;
}
/* ----------------------------------------------------------------------
Compute particle velocity is distance/time units
------------------------------------------------------------------------- */
double FixNPHugOMP::compute_up()
{
double v;
double eps,us,up;
v = compute_vol();
us = compute_us();
// u = eps*Us
eps = 1.0 - v/v0;
up = us*eps;
return up;
}
// look for index in local class
// if index not found, look in base class
double FixNPHugOMP::compute_vector(int n)
{
int ilen;
// n = 0: Hugoniot energy difference (temperature units)
ilen = 1;
if (n < ilen) return compute_hugoniot();
n -= ilen;
// n = 1: Shock velocity
ilen = 1;
if (n < ilen) return compute_us();
n -= ilen;
// n = 2: Particle velocity
ilen = 1;
if (n < ilen) return compute_up();
n -= ilen;
// index not found, look in base class
return FixNHOMP::compute_vector(n);
}
/* ----------------------------------------------------------------------
pack restart data
------------------------------------------------------------------------- */
int FixNPHugOMP::pack_restart_data(double *list)
{
int n = 0;
list[n++] = e0;
list[n++] = v0;
list[n++] = p0;
// call the base class function
n += FixNHOMP::pack_restart_data(list+n);
return n;
}
/* ----------------------------------------------------------------------
calculate the number of data to be packed
------------------------------------------------------------------------- */
int FixNPHugOMP::size_restart_global()
{
int nsize = 3;
// call the base class function
nsize += FixNHOMP::size_restart_global();
return nsize;
}
/* ----------------------------------------------------------------------
use state info from restart file to restart the Fix
------------------------------------------------------------------------- */
void FixNPHugOMP::restart(char *buf)
{
int n = 0;
double *list = (double *) buf;
e0 = list[n++];
v0 = list[n++];
p0 = list[n++];
e0_set = 1;
v0_set = 1;
p0_set = 1;
// call the base class function
buf += n*sizeof(double);
FixNHOMP::restart(buf);
}
/* ---------------------------------------------------------------------- */
int FixNPHugOMP::modify_param(int narg, char **arg)
{
if (strcmp(arg[0],"e0") == 0) {
if (narg < 2) error->all(FLERR,"Illegal fix nphug/omp command");
e0 = force->numeric(FLERR,arg[1]);
e0_set = 1;
return 2;
} else if (strcmp(arg[0],"v0") == 0) {
if (narg < 2) error->all(FLERR,"Illegal fix nphug/omp command");
v0 = force->numeric(FLERR,arg[1]);
v0_set = 1;
return 2;
} else if (strcmp(arg[0],"p0") == 0) {
if (narg < 2) error->all(FLERR,"Illegal fix nphug/omp command");
p0 = force->numeric(FLERR,arg[1]);
p0_set = 1;
return 2;
}
return 0;
}
Event Timeline
Log In to Comment