Boundary conditions
Lagrangian boundary conditions are based on boundary zone (cs_boundary_zone_t) definitions. Additional information may be provided for Lagrangian boundary types and injections.
As usual, definitions may be created using the GUI and extended with user functions.
Access to the Lagrangian boundary conditions structure, which is necessary to most of the following examples, may be done as follows:
cs_lagr_zone_data_t * cs_lagr_get_boundary_conditions(void)
Return pointer to the main boundary conditions structure.
Definition: cs_lagr.c:1522
Definition: cs_lagr.h:724
Boundary zones
In this example, we assign rebound conditions to all boundary zones, except for an inlet and outlet type to specified zones. The type assigned is an integer based on the cs_lagr_bc_type_t enumerator type.
{
for (int z_id = 0; z_id < n_zones; z_id++) {
}
}
const cs_zone_t * cs_boundary_zone_by_name(const char *name)
Return a pointer to a boundary zone based on its name if present.
Definition: cs_boundary_zone.c:711
int cs_boundary_zone_n_zones(void)
Return number of boundary zones defined.
Definition: cs_boundary_zone.c:426
@ CS_LAGR_OUTLET
Definition: cs_lagr.h:88
@ CS_LAGR_INLET
Definition: cs_lagr.h:87
@ CS_LAGR_REBOUND
Definition: cs_lagr.h:89
int * zone_type
Definition: cs_lagr.h:729
int id
Definition: cs_zone.h:59
Injection sets
In the following example, a first injection set for an inlet zone is defined. Note that newly injected particles may also be modified using the cs_user_lagr_in function.
{
int set_id = 0;
}
}
cs_lagr_injection_set_t * cs_lagr_get_injection_set(cs_lagr_zone_data_t *zone_data, int zone_id, int set_id)
Provide access to injection set structure.
Definition: cs_lagr.c:1163
cs_lagr_model_t * cs_glob_lagr_model
cs_lagr_specific_physics_t * cs_glob_lagr_specific_physics
Definition: cs_lagr.h:567
cs_real_t diameter_variance
Definition: cs_lagr.h:611
cs_real_t density
Definition: cs_lagr.h:627
int injection_frequency
Definition: cs_lagr.h:576
int temperature_profile
Definition: cs_lagr.h:594
cs_real_t velocity_magnitude
Definition: cs_lagr.h:605
int velocity_profile
Definition: cs_lagr.h:589
cs_real_t cp
Definition: cs_lagr.h:631
cs_real_t diameter
Definition: cs_lagr.h:610
cs_gnum_t n_inject
Definition: cs_lagr.h:573
int cluster
Definition: cs_lagr.h:600
cs_real_t fouling_index
Definition: cs_lagr.h:629
cs_real_t flow_rate
Definition: cs_lagr.h:635
cs_real_t emissivity
Definition: cs_lagr.h:637
cs_real_t stat_weight
Definition: cs_lagr.h:633
cs_real_t temperature
Definition: cs_lagr.h:608
int n_stat_classes
Definition: cs_lagr.h:339
int itpvar
Definition: cs_lagr.h:418
In the next example, a profile is assigned to the second injection set of an inlet zone (it is assumed this et was previously defined either through the GUI or user function).
This requires first defining a profile definition function, matching the profile of cs_lagr_injection_profile_compute_t. An example based on experimental profiles is given here:
static void
_injection_profile(int zone_id,
int location_id,
const void *input,
{
const int itmx = 8;
cs_real_t zi[] = {0.e-3, 1.e-3, 1.5e-3, 2.0e-3, 2.5e-3, 3.0e-3, 3.5e-3,
4.0e-3, 4.5e-3, 5.0e-3};
cs_real_t lvf[] = {0.377e-4, 2.236e-4, 3.014e-4, 4.306e-4, 5.689e-4,
8.567e-4, 7.099e-4, 4.520e-4, 2.184e-4, 0.377e-4};
cs_real_t ui[] = {5.544, 8.827, 9.068, 9.169, 8.923, 8.295, 7.151, 6.048,
4.785, 5.544};
const cs_real_t z = b_face_coords[face_id][2];
int i = 0;
if (z > zi[0]) {
for (i = 0; i < itmx; i++) {
if (z >= zi[i] && z < zi[i+1])
break;
}
}
cs_real_t up = ui[i] +(z-zi[i])*(ui[i+1]-ui[i])/(zi[i+1]-zi[i]);
cs_real_t lvfp = lvf[i] + (z-zi[i])*(lvf[i+1]-lvf[i])/(zi[i+1]-zi[i]);
profile[ei] = lvfp * up;
}
}
double cs_real_t
Floating-point value.
Definition: cs_defs.h:332
cs_real_t cs_real_3_t[3]
vector of 3 floating-point values
Definition: cs_defs.h:347
int cs_lnum_t
local mesh entity id
Definition: cs_defs.h:325
cs_mesh_quantities_t * cs_glob_mesh_quantities
cs_real_t * b_face_cog
Definition: cs_mesh_quantities.h:111
Assigning the profile to the injection set simply requires assigning the function to the pointer in the injection set structure:
{
int set_id = 1;
}
cs_lagr_injection_profile_compute_t * injection_profile_func
Definition: cs_lagr.h:580
void * injection_profile_input
Definition: cs_lagr.h:583
An optional user-defined input function may also be associated.
Boundary-particle interactions
It is also possible to decide of the behavior of particle when they encounter a boundary (this boundary has to be of type CS_LAGR_BC_USER).
In the following example, the particle is simply deposited and marked for elimination:
# pragma omp atomic
particles->n_part_dep += 1;
# pragma omp atomic
p_id,
for (
int k = 0;
k < 3;
k++)
particle_coord[
k] = c_intersect[
k];
@ k
Definition: cs_field_pointer.h:70
#define CS_EVENT_OUTFLOW
Definition: cs_lagr_event.h:56
#define CS_EVENT_DEPOSITION
Definition: cs_lagr_event.h:62
@ CS_LAGR_STAT_WEIGHT
Definition: cs_lagr_particle.h:90
@ CS_LAGR_COORDS
Definition: cs_lagr_particle.h:95
static void cs_lagr_particles_set_flag(const cs_lagr_particle_set_t *particle_set, cs_lnum_t particle_id, int mask)
Set flag value with a selected mask for a given particle in a set.
Definition: cs_lagr_particle.h:538
static void * cs_lagr_particles_attr(cs_lagr_particle_set_t *particle_set, cs_lnum_t particle_id, cs_lagr_attribute_t attr)
Get pointer to a current attribute of a given particle in a set.
Definition: cs_lagr_particle.h:412
#define CS_LAGR_PART_DEPOSITED
Definition: cs_lagr_particle.h:57
static cs_real_t cs_lagr_particles_get_real(const cs_lagr_particle_set_t *particle_set, cs_lnum_t particle_id, cs_lagr_attribute_t attr)
Get attribute value of type cs_real_t of a given particle in a set.
Definition: cs_lagr_particle.h:798
@ CS_LAGR_PART_OUT
Definition: cs_lagr_tracking.h:60
Volume conditions
Lagrangian volume conditions are based on volume zone (cs_volume_zone_t) definitions. Additional information may be provided for Lagrangian injections.
As usual, definitions may be created using the GUI and extended with user functions.
Access to the Lagrangian volume conditions structure, which is necessary to most of the following examples, may be done as follows:
cs_lagr_zone_data_t * cs_lagr_get_volume_conditions(void)
Return pointer to the main volume conditions structure.
Definition: cs_lagr.c:1546
Injection sets
In the following example, we inject 1 particle set at each time step:
{
int set_id = 0;
}
}
cs_lagr_agglomeration_model_t * cs_glob_lagr_agglomeration_model
const cs_zone_t * cs_volume_zone_by_name(const char *name)
Return a pointer to a volume zone based on its name if present.
Definition: cs_volume_zone.c:677
cs_real_t base_diameter
Definition: cs_lagr.h:521
int aggregat_class_id
Definition: cs_lagr.h:602
cs_real_t aggregat_fractal_dim
Definition: cs_lagr.h:603
int fragmentation
Definition: cs_lagr.h:337
int agglomeration
Definition: cs_lagr.h:333
{
for (int set_id = 0; set_id < 2; set_id++) {
}
}
unsigned long cs_gnum_t
global mesh entity number
Definition: cs_defs.h:310
const cs_zone_t * cs_volume_zone_by_id(int id)
Return a pointer to a volume zone based on its id.
Definition: cs_volume_zone.c:653
double precision, dimension(:,:,:), allocatable density
Definition: atimbr.f90:123
In the following example, we inject 2 particle sets at computation initialization (i.e. at the first time step of a computation sequence in which the Lagrangian module is activated). Note that newly injected particles may also be modified using the cs_user_lagr_in function.
{
for (int set_id = 0; set_id < 2; set_id++) {
}
}
External force
User definition of an external force field acting on the particles.
It must be prescribed in every cell and be homogeneous to gravity (m/s^2) By default gravity and drag force are the only forces acting on the particles (the gravity components gx gy gz are assigned in the GUI or in cs_user_parameters)
void
{
fextla[ip][0] = 0;
fextla[ip][1] = 0;
fextla[ip][2] = 0;
}
}
cs_real_t cs_real_33_t[3][3]
3x3 matrix of floating-point values
Definition: cs_defs.h:356
cs_lagr_particle_set_t * cs_lagr_get_particle_set(void)
Return pointer to the main cs_lagr_particle_set_t structure.
Definition: cs_lagr_particle.c:1171
void cs_user_lagr_ef(cs_real_t dt_p, const cs_real_t taup[], const cs_real_3_t tlag[], const cs_real_3_t piil[], const cs_real_33_t bx[], const cs_real_t tsfext[], const cs_real_33_t vagaus[], const cs_real_3_t gradpr[], const cs_real_33_t gradvf[], cs_real_t rho_p[], cs_real_3_t fextla[])
User definition of an external force field acting on the particles.
Definition: cs_user_lagr_particle.c:87
Definition: cs_lagr_particle.h:222
cs_lnum_t n_particles
Definition: cs_lagr_particle.h:224
Impose motion on a particle
Impose the motion of a particle flagged CS_LAGR_PART_IMPOSED_MOTION by modifying the particle position and its velocity.
void
{
disp[0] = 0.;
disp[1] = rcost * (cos(omega*
dt) - 1.0 ) - rsint * sin(omega*
dt);
disp[2] = rsint * (cos(omega*
dt) - 1.0 ) + rcost * sin(omega*
dt);
}
@ dt
Definition: cs_field_pointer.h:65
void cs_user_lagr_imposed_motion(const cs_real_t coords[3], const cs_real_t dt, cs_real_t disp[3])
Impose the motion of a particle flagged CS_LAGR_PART_IMPOSED_MOTION.
Definition: cs_user_lagr_particle.c:146
Modification of newly injected particles
User modification of newly injected particles.
This function is called after the initialization of the new particles in order to modify them according to new particle profiles (injection profiles, position of the injection point, statistical weights, correction of the diameter if the standard-deviation option is activated).
This function is called for each injection zone and set. Particles with ids between pset->n_particles and n_elts are initialized but may be modidied by this function.
void
{
for (
cs_lnum_t p_id = particle_range[0]; p_id < particle_range[1]; p_id++) {
part_vel[0] = 1.0;
part_vel[1] = 0.0;
part_vel[2] = 0.0;
attr_id++) {
*user_var = 0.;
}
}
if (particle_range[1] <= particle_range[0])
return;
for (
cs_lnum_t ip = particle_range[0]; ip < particle_range[1]; ip++) {
_inlet2(particles, ip);
}
}
{
int time_id = 1;
time_id = 0;
time_id,
visc_length);
}
}
cs_lagr_source_terms_t * cs_glob_lagr_source_terms
cs_lagr_time_scheme_t * cs_glob_lagr_time_scheme
void cs_lagr_new_particle_init(const cs_lnum_t particle_range[2], int time_id, const cs_real_t visc_length[])
Initialization for new particles.
Definition: cs_lagr_new.c:658
@ CS_LAGR_USER
Definition: cs_lagr_particle.h:177
@ CS_LAGR_VELOCITY
Definition: cs_lagr_particle.h:96
@ CS_LAGR_TEMPERATURE
Definition: cs_lagr_particle.h:147
@ CS_LAGR_DIAMETER
Definition: cs_lagr_particle.h:93
static void cs_lagr_particles_set_real(cs_lagr_particle_set_t *particle_set, cs_lnum_t particle_id, cs_lagr_attribute_t attr, cs_real_t value)
Set attribute value of type cs_real_t of a given particle in a set.
Definition: cs_lagr_particle.h:848
void cs_user_lagr_in(cs_lagr_particle_set_t *particles, const cs_lagr_injection_set_t *zis, const cs_lnum_t particle_range[2], const cs_lnum_t particle_face_id[], const cs_real_t visc_length[])
User modification of newly injected particles.
Definition: cs_user_lagr_particle.c:181
cs_lagr_stat_options_t * cs_glob_lagr_stat_options
const cs_time_step_t * cs_glob_time_step
int n_user_variables
Definition: cs_lagr.h:341
int nstits
Definition: cs_lagr.h:698
int nstist
Definition: cs_lagr_stat.h:213
int isttio
Definition: cs_lagr.h:211
int nt_cur
Definition: cs_time_step.h:74
Here is another example of the modification of newly injected particles:
int coal_id = 0;
cs_real_t initial_diameter = 0, shrinking_diameter = 0;
for (int l_id = 0; l_id < n_layers; l_id++) {
temperature[l_id] = 0;
coal_mass_fraction[l_id] = 0;
coke_density[l_id] = 0;
coke_mass_fraction[l_id] = 0;
}
coal_id = 0;
* (1.0 - (cm->
y1ch[coal_id] + cm->
y2ch[coal_id]) / 2.0);
water_mass_f = 0.0;
for (int l_id = 0; l_id < n_layers; l_id++) {
temperature[l_id] = 800 - 273.15;
coal_mass_fraction[l_id] = 0.;
coke_density[l_id]
* (1.0 - (cm->
y1ch[coal_id] + cm->
y2ch[coal_id]) / 2.0);
coke_mass_fraction[l_id] = coke_density[l_id] /
density;
}
}
for (
cs_lnum_t p_id = particle_range[0]; p_id < particle_range[1]; p_id++) {
water_mass_f * mass);
for (int l_id = 0; l_id < n_layers; l_id++) {
particle_temperature[l_id] = temperature[l_id];
particle_coal_mass[l_id] = coal_mass_fraction[l_id] * mass / n_layers;
particle_coke_mass[l_id] = coke_mass_fraction[l_id] * mass / n_layers;
particle_coal_density[l_id] = coke_density[l_id];
}
shrinking_diameter);
initial_diameter);
}
cs_coal_model_t * cs_glob_coal_model
Definition: cs_coal.c:90
@ cp
Definition: cs_field_pointer.h:100
@ CS_LAGR_COAL_DENSITY
Definition: cs_lagr_particle.h:161
@ CS_LAGR_MASS
Definition: cs_lagr_particle.h:92
@ CS_LAGR_COAL_MASS
Definition: cs_lagr_particle.h:154
@ CS_LAGR_COKE_MASS
Definition: cs_lagr_particle.h:155
@ CS_LAGR_CP
Definition: cs_lagr_particle.h:149
@ CS_LAGR_INITIAL_DIAMETER
Definition: cs_lagr_particle.h:158
@ CS_LAGR_SHRINKING_DIAMETER
Definition: cs_lagr_particle.h:157
@ CS_LAGR_WATER_MASS
Definition: cs_lagr_particle.h:153
const cs_real_t cs_math_pi
double y2ch[CS_COMBUSTION_MAX_COALS]
Definition: cs_coal.h:300
double y1ch[CS_COMBUSTION_MAX_COALS]
Definition: cs_coal.h:291
double cp2ch[CS_COMBUSTION_MAX_COALS]
Definition: cs_coal.h:258
double xwatch[CS_COMBUSTION_MAX_COALS]
Definition: cs_coal.h:267
double xashch[CS_COMBUSTION_MAX_COALS]
Definition: cs_coal.h:264
double rho0ch[CS_COMBUSTION_MAX_COALS]
Definition: cs_coal.h:216
int zone_id
Definition: cs_lagr.h:569
int set_id
Definition: cs_lagr.h:570
int n_temperature_layers
Definition: cs_lagr.h:278