/** Calculate the local fluid stress.
* The calculation is implemented explicitly for the special case of D3Q19.
* @param index The local lattice site (Input).
* @param pi local fluid pressure
*/
inline void lb_calc_local_pi(index_t index, double *pi) {
double rho;
double j[3];
if (!(lattice_switch & LATTICE_LB)) {
runtimeErrorMsg() <<"Error in lb_calc_local_pi in " << __FILE__ << __LINE__ << ": CPU LB not switched on.";
j[0] = j[1] = j[2] = 0;
return;
}
lb_calc_local_fields(index, &rho, j, pi);
}
/** Calculate the local fluid stress.
* The calculation is implemented explicitly for the special case of D3Q19.
* @param index The local lattice site (Input).
* @param pi local fluid pressure
*/
inline void lb_calc_local_pi(index_t index, double *pi) {
double rho;
double j[3];
if (!(lattice_switch & LATTICE_LB)) {
ERROR_SPRINTF(runtime_error(128),
"{ Error in lb_calc_local_pi in %s %d: CPU LB not switched on. } ", __FILE__, __LINE__);
j[0] = j[1] = j[2] = 0;
return;
}
lb_calc_local_fields(index, &rho, j, pi);
}
/** Calculate temperature of the LB fluid.
* \param result Fluid temperature
*/
void lb_calc_fluid_temp(double *result) {
int x, y, z, index;
double rho, j[3];
double temp = 0.0;
for (x=1; x<=lblattice.grid[0]; x++) {
for (y=1; y<=lblattice.grid[1]; y++) {
for (z=1; z<=lblattice.grid[2]; z++) {
index = get_linear_index(x,y,z,lblattice.halo_grid);
lb_calc_local_fields(index, &rho, j, NULL);
temp += scalar(j,j);
}
}
}
temp *= 1./(3.*lbpar.rho*lblattice.grid_volume*lbpar.tau*lbpar.tau*lblattice.agrid);
MPI_Reduce(&temp, result, 1, MPI_DOUBLE, MPI_SUM, 0, MPI_COMM_WORLD);
}
/** Calculate a velocity profile for the LB fluid. */
void lb_calc_velprof(double *result, int *params) {
int index, dir[3], grid[3];
int newroot=0, subrank, involved=0;
double rho, j[3], *velprof;
MPI_Comm slice_comm = NULL;
MPI_Status status;
if (this_node != 0) params = malloc(4*sizeof(int));
MPI_Bcast(params, 4, MPI_INT, 0, MPI_COMM_WORLD);
int vcomp = params[0];
int pdir = params[1];
int x1 = params[2];
int x2 = params[3];
dir[pdir] = 0;
dir[(pdir+1)%3] = x1;
dir[(pdir+2)%3] = x2;
//fprintf(stderr,"%d: (%d,%d,%d)\n",this_node,dir[0],dir[1],dir[2]);
newroot = map_lattice_to_node(&lblattice, dir, grid);
map_node_array(this_node, node_pos);
//fprintf(stderr,"%d: newroot=%d (%d,%d,%d)\n",this_node,newroot,grid[0],grid[1],grid[2]);
if ( (grid[(pdir+1)%3] == node_pos[(pdir+1)%3])
&& (grid[(pdir+2)%3] == node_pos[(pdir+2)%3]) ) {
involved = 1;
}
MPI_Comm_split(MPI_COMM_WORLD, involved, this_node, &slice_comm);
MPI_Comm_rank(slice_comm, &subrank);
if (this_node == newroot)
result = realloc(result,box_l[pdir]/lblattice.agrid*sizeof(double));
//fprintf(stderr,"%d (%d,%d): result=%p vcomp=%d pdir=%d x1=%d x2=%d involved=%d\n",this_node,subrank,newroot,result,vcomp,pdir,x1,x2,involved);
if (involved) {
velprof = malloc(lblattice.grid[pdir]*sizeof(double));
//dir[(pdir+1)%3] += 1;
//dir[(pdir+2)%3] += 1;
for (dir[pdir]=1;dir[pdir]<=lblattice.grid[pdir];dir[pdir]++) {
index = get_linear_index(dir[0],dir[1],dir[2],lblattice.halo_grid);
lb_calc_local_fields(index, &rho, j, NULL);
//fprintf(stderr,"%p %d %.12e %.12e %d\n",lbfluid[0],index,rho,j[0],vcomp);
if (rho < ROUND_ERROR_PREC) {
velprof[dir[pdir]-1] = 0.0;
} else {
//velprof[dir[pdir]-1] = local_j / (SQR(lbpar.agrid)*lbpar.tau);
velprof[dir[pdir]-1] = j[vcomp]/rho * lblattice.agrid/lbpar.tau;
//fprintf(stderr,"%f %f %f\n",velprof[dir[pdir]-1],local_j,local_rho);
}
//if (dir[pdir]==lblattice.grid[pdir]) {
// int i;
// fprintf(stderr,"(%d,%d,%d)\n",dir[0],dir[1],dir[2]);
// fprintf(stderr,"%d\n",lbfluid[index].boundary);
// for (i=0;i<lbmodel.n_veloc;i++) fprintf(stderr,"local_n[%p][%d]=%.12e\n",lbfluid[index].n,i,lbfluid[index].n[i]+lbmodel.coeff[i][0]*lbpar.rho);
// fprintf(stderr,"local_rho=%e\n",local_rho);
// fprintf(stderr,"local_j=%e\n",local_j);
//}
}
MPI_Gather(velprof, lblattice.grid[pdir], MPI_DOUBLE, result, lblattice.grid[pdir], MPI_DOUBLE, newroot, slice_comm);
free(velprof);
}
MPI_Comm_free(&slice_comm);
if (newroot != 0) {
if (this_node == newroot) {
MPI_Send(result, lblattice.grid[pdir]*node_grid[pdir], MPI_DOUBLE, 0, REQ_VELPROF, MPI_COMM_WORLD);
free(result);
}
if (this_node == 0) {
//fprintf(stderr,"%d: I'm just here!\n",this_node);
MPI_Recv(result, lblattice.grid[pdir]*node_grid[pdir], MPI_DOUBLE, newroot, REQ_VELPROF, MPI_COMM_WORLD, &status);
//fprintf(stderr,"%d: And now I'm here!\n",this_node);
}
}
if (this_node !=0) free(params);
}
