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BCSubsonicOutflow.c File Reference

Subsonic outflow boundary conditions (specific to Euler/Navier-Stokes systems) More...

#include <stdlib.h>
#include <basic.h>
#include <arrayfunctions.h>
#include <boundaryconditions.h>
#include <physicalmodels/euler2d.h>
#include <physicalmodels/navierstokes3d.h>

Go to the source code of this file.

Functions

int BCSubsonicOutflowU (void *b, void *m, int ndims, int nvars, int *size, int ghosts, double *phi, double waqt)
 

Detailed Description

Subsonic outflow boundary conditions (specific to Euler/Navier-Stokes systems)

Author
Debojyoti Ghosh

Definition in file BCSubsonicOutflow.c.

Function Documentation

int BCSubsonicOutflowU ( void *  b,
void *  m,
int  ndims,
int  nvars,
int *  size,
int  ghosts,
double *  phi,
double  waqt 
)

Applies the subsonic outflow boundary condition: The pressure at the physical boundary ghost points is specified, while the density and velocity are extrapolated from the interior. This boundary condition is specific to two and three dimensional Euler/ Navier-Stokes systems (Euler2D, NavierStokes2D, NavierStokes3D).

Parameters
bBoundary object of type DomainBoundary
mMPI object of type MPIVariables
ndimsNumber of spatial dimensions
nvarsNumber of variables/DoFs per grid point
sizeInteger array with the number of grid points in each spatial dimension
ghostsNumber of ghost points
phiThe solution array on which to apply the boundary condition
waqtCurrent solution time

Definition at line 19 of file BCSubsonicOutflow.c.

29 {
30  DomainBoundary *boundary = (DomainBoundary*) b;
31 
32  int dim = boundary->dim;
33  int face = boundary->face;
34 
35  if (ndims == 2) {
36 
37  /* create a fake physics object */
38  Euler2D physics;
39  double gamma;
40  gamma = physics.gamma = boundary->gamma;
41  double inv_gamma_m1 = 1.0/(gamma-1.0);
42 
43  if (boundary->on_this_proc) {
44  int bounds[ndims], indexb[ndims], indexi[ndims];
45  _ArraySubtract1D_(bounds,boundary->ie,boundary->is,ndims);
46  _ArraySetValue_(indexb,ndims,0);
47  int done = 0;
48  while (!done) {
49  int p1, p2;
50  _ArrayCopy1D_(indexb,indexi,ndims);
51  _ArrayAdd1D_(indexi,indexi,boundary->is,ndims);
52  if (face == 1) indexi[dim] = ghosts-1-indexb[dim];
53  else if (face == -1) indexi[dim] = size[dim]-indexb[dim]-1;
54  else return(1);
55  _ArrayIndex1DWO_(ndims,size,indexb,boundary->is,ghosts,p1);
56  _ArrayIndex1D_(ndims,size,indexi,ghosts,p2);
57 
58  /* flow variables in the interior */
59  double rho, uvel, vvel, energy, pressure;
60  double rho_gpt, uvel_gpt, vvel_gpt, energy_gpt, pressure_gpt;
61  _Euler2DGetFlowVar_((phi+nvars*p2),rho,uvel,vvel,energy,pressure,(&physics));
62  /* set the ghost point values */
63  rho_gpt = rho;
64  pressure_gpt = pressure; /* useless statement to avoid compiler warning */
65  pressure_gpt = boundary->FlowPressure;
66  uvel_gpt = uvel;
67  vvel_gpt = vvel;
68  energy_gpt = inv_gamma_m1*pressure_gpt
69  + 0.5 * rho_gpt * (uvel_gpt*uvel_gpt + vvel_gpt*vvel_gpt);
70 
71  phi[nvars*p1+0] = rho_gpt;
72  phi[nvars*p1+1] = rho_gpt * uvel_gpt;
73  phi[nvars*p1+2] = rho_gpt * vvel_gpt;
74  phi[nvars*p1+3] = energy_gpt;
75 
76  _ArrayIncrementIndex_(ndims,bounds,indexb,done);
77  }
78  }
79 
80  } else if (ndims == 3) {
81 
82  /* create a fake physics object */
83  double gamma;
84  gamma = boundary->gamma;
85  double inv_gamma_m1 = 1.0/(gamma-1.0);
86 
87  if (boundary->on_this_proc) {
88  int bounds[ndims], indexb[ndims], indexi[ndims];
89  _ArraySubtract1D_(bounds,boundary->ie,boundary->is,ndims);
90  _ArraySetValue_(indexb,ndims,0);
91  int done = 0;
92  while (!done) {
93  int p1, p2;
94  _ArrayCopy1D_(indexb,indexi,ndims);
95  _ArrayAdd1D_(indexi,indexi,boundary->is,ndims);
96  if (face == 1) indexi[dim] = ghosts-1-indexb[dim];
97  else if (face == -1) indexi[dim] = size[dim]-indexb[dim]-1;
98  else return(1);
99  _ArrayIndex1DWO_(ndims,size,indexb,boundary->is,ghosts,p1);
100  _ArrayIndex1D_(ndims,size,indexi,ghosts,p2);
101 
102  /* flow variables in the interior */
103  double rho, uvel, vvel, wvel, energy, pressure;
104  double rho_gpt, uvel_gpt, vvel_gpt, wvel_gpt, energy_gpt, pressure_gpt;
105  _NavierStokes3DGetFlowVar_((phi+nvars*p2),_NavierStokes3D_stride_,rho,uvel,vvel,wvel,energy,pressure,gamma);
106  /* set the ghost point values */
107  rho_gpt = rho;
108  pressure_gpt = pressure; /* useless statement to avoid compiler warning */
109  pressure_gpt = boundary->FlowPressure;
110  uvel_gpt = uvel;
111  vvel_gpt = vvel;
112  wvel_gpt = wvel;
113  energy_gpt = inv_gamma_m1*pressure_gpt
114  + 0.5 * rho_gpt
115  * (uvel_gpt*uvel_gpt + vvel_gpt*vvel_gpt + wvel_gpt*wvel_gpt);
116 
117  phi[nvars*p1+0] = rho_gpt;
118  phi[nvars*p1+1] = rho_gpt * uvel_gpt;
119  phi[nvars*p1+2] = rho_gpt * vvel_gpt;
120  phi[nvars*p1+3] = rho_gpt * wvel_gpt;
121  phi[nvars*p1+4] = energy_gpt;
122 
123  _ArrayIncrementIndex_(ndims,bounds,indexb,done);
124  }
125  }
126 
127  }
128  return(0);
129 }
#define _NavierStokes3DGetFlowVar_(u, stride, rho, vx, vy, vz, e, P, gamma)
#define _ArraySetValue_(x, size, value)
#define _ArrayIncrementIndex_(N, imax, i, done)
#define _Euler2DGetFlowVar_(u, rho, vx, vy, e, P, p)
Definition: euler2d.h:44
#define _ArraySubtract1D_(x, a, b, size)
#define _ArrayIndex1D_(N, imax, i, ghost, index)
Structure containing the variables and function pointers defining a boundary.
#define _ArrayIndex1DWO_(N, imax, i, offset, ghost, index)
#define _ArrayCopy1D_(x, y, size)
#define _ArrayAdd1D_(x, a, b, size)
double gamma
Definition: euler2d.h:245
static const int _NavierStokes3D_stride_