void YPlus::execute()
{
Mesh& mesh = this->mesh();
// Geometry data
const Field& coords = mesh.geometry_fields().coordinates();
const Uint nb_nodes = coords.size();
const Uint dim = coords.row_size();
// Velocity data
const Field& velocity_field = common::find_component_recursively_with_tag<Field>(mesh, options().value<std::string>("velocity_tag"));
const auto velocity_dict_handle = Handle<Dictionary const>(velocity_field.parent());
cf3_assert(velocity_dict_handle != nullptr);
const Dictionary& velocity_dict = *velocity_dict_handle;
const Uint vel_offset = velocity_field.descriptor().offset("Velocity");
// initialize if needed
auto volume_node_connectivity = Handle<NodeConnectivity>(mesh.get_child("volume_node_connectivity"));
if(m_normals.empty())
{
// Node-to-element connectivity for the volume elements
volume_node_connectivity = mesh.create_component<NodeConnectivity>("volume_node_connectivity");
std::vector< Handle<Entities const> > volume_entities;
for(const mesh::Elements& elements : common::find_components_recursively_with_filter<mesh::Elements>(mesh, IsElementsVolume()))
{
volume_entities.push_back(elements.handle<Entities const>());
}
volume_node_connectivity->initialize(nb_nodes, volume_entities);
mesh.geometry_fields().create_field("wall_velocity_gradient_nodal").add_tag("wall_velocity_gradient_nodal");
Dictionary& wall_P0 = *mesh.create_component<DiscontinuousDictionary>("wall_P0");
m_normals.clear();
for(const Handle<Region>& region : regions())
{
for(mesh::Elements& wall_entity : common::find_components_recursively_with_filter<mesh::Elements>(*region, IsElementsSurface()))
{
const Uint nb_elems = wall_entity.size();
const auto& geom_conn = wall_entity.geometry_space().connectivity();
const ElementType& etype = wall_entity.element_type();
const Uint element_nb_nodes = etype.nb_nodes();
m_normals.push_back(std::vector<RealVector>(nb_elems, RealVector(dim)));
RealMatrix elem_coords(element_nb_nodes, dim);
for(Uint elem_idx = 0; elem_idx != nb_elems; ++elem_idx)
{
const Connectivity::ConstRow conn_row = geom_conn[elem_idx];
fill(elem_coords, coords, conn_row);
RealVector normal(dim);
etype.compute_normal(elem_coords, m_normals.back()[elem_idx]);
m_normals.back()[elem_idx] /= m_normals.back()[elem_idx].norm();
}
wall_entity.create_component<FaceConnectivity>("wall_face_connectivity")->initialize(*volume_node_connectivity);
wall_entity.create_space("cf3.mesh.LagrangeP0."+wall_entity.element_type().shape_name(),wall_P0);
}
}
wall_P0.build(); // to tell the dictionary that all spaces have been added
mesh.update_structures(); // to tell the mesh there is a new dictionary added manually
wall_P0.create_field("wall_velocity_gradient").add_tag("wall_velocity_gradient");
}
// Create the y+ field in the geometry dictionary
if(common::find_component_ptr_with_tag(mesh.geometry_fields(), "yplus") == nullptr)
{
mesh.geometry_fields().create_field("yplus").add_tag("yplus");
}
// Compute shear stress
Uint surface_idx = 0;
Dictionary& wall_P0 = *Handle<mesh::Dictionary>(mesh.get_child_checked("wall_P0"));
Field& wall_velocity_gradient_field = *Handle<Field>(wall_P0.get_child_checked("wall_velocity_gradient"));
for(const Handle<Region>& region : regions())
{
for(const mesh::Elements& elements : common::find_components_recursively_with_filter<mesh::Elements>(*region, IsElementsSurface()))
{
const Uint nb_elements = elements.geometry_space().connectivity().size();
cf3_assert(elements.element_type().nb_faces() == 1);
const auto& face_connectivity = *Handle<FaceConnectivity const>(elements.get_child_checked("wall_face_connectivity"));
const auto& wall_conn = elements.space(wall_P0).connectivity();
for(Uint surface_elm_idx = 0; surface_elm_idx != nb_elements; ++surface_elm_idx)
{
if(face_connectivity.has_adjacent_element(surface_elm_idx, 0))
{
const Uint wall_field_idx = wall_conn[surface_elm_idx][0];
// Get the wall normal vector
const RealVector& normal = m_normals[surface_idx][surface_elm_idx];
RealVector3 normal3;
normal3[0] = normal[0];
normal3[1] = normal[1];
normal3[2] = dim == 3 ? normal[2] : 0.;
// The connected volume element
NodeConnectivity::ElementReferenceT connected = face_connectivity.adjacent_element(surface_elm_idx, 0);
const mesh::Entities& volume_entities = *face_connectivity.node_connectivity().entities()[connected.first];
const Uint volume_elem_idx = connected.second;
const auto& velocity_conn = volume_entities.space(velocity_dict).connectivity();
const auto& velocity_sf = volume_entities.space(velocity_dict).shape_function();
const auto& geom_conn = volume_entities.geometry_space().connectivity();
const ElementType& volume_etype = volume_entities.element_type();
const Uint nb_vel_nodes = velocity_sf.nb_nodes();
const RealVector centroid_mapped_coord = 0.5*(velocity_sf.local_coordinates().colwise().minCoeff() + velocity_sf.local_coordinates().colwise().maxCoeff());
RealMatrix elem_coords(geom_conn.row_size(), dim);
fill(elem_coords, coords, geom_conn[volume_elem_idx]);
RealVector tangential_velocity(nb_vel_nodes); // For every node, the component of the velocity tangential to the wall
RealVector3 v3;
for(Uint i = 0; i != nb_vel_nodes; ++i)
{
Eigen::Map<RealVector const> v(&velocity_field[velocity_conn[volume_elem_idx][i]][vel_offset], dim);
v3[0] = v[0];
v3[1] = v[1];
v3[2] = dim == 3 ? v[2] : 0.;
tangential_velocity[i] = v3.cross(normal3).norm();
}
wall_velocity_gradient_field[wall_field_idx][0] = fabs((volume_etype.jacobian(centroid_mapped_coord, elem_coords).inverse() * velocity_sf.gradient(centroid_mapped_coord) * tangential_velocity).dot(-normal));
}
}
++surface_idx;
}
}
wall_velocity_gradient_field.synchronize();
// Compute a nodal version of the wall velocity gradient
const auto& wall_node_connectivity = *Handle<NodeConnectivity>(mesh.get_child_checked("wall_node_connectivity"));
Field& wall_velocity_gradient_field_nodal = *Handle<Field>(mesh.geometry_fields().get_child_checked("wall_velocity_gradient_nodal"));
for(Uint node_idx = 0; node_idx != nb_nodes; ++node_idx)
{
Uint nb_connected_elems = 0;
wall_velocity_gradient_field_nodal[node_idx][0] = 0;
for(const NodeConnectivity::ElementReferenceT elref : wall_node_connectivity.node_element_range(node_idx))
{
const Uint wall_field_idx = wall_node_connectivity.entities()[elref.first]->space(wall_P0).connectivity()[elref.second][0];
wall_velocity_gradient_field_nodal[node_idx][0] += wall_velocity_gradient_field[wall_field_idx][0];
++nb_connected_elems;
}
if(nb_connected_elems != 0)
{
wall_velocity_gradient_field_nodal[node_idx][0] /= static_cast<Real>(nb_connected_elems);
}
}
// Set Yplus
Field& yplus_field = *Handle<Field>(mesh.geometry_fields().get_child_checked("yplus"));
const Field& wall_distance_field = *Handle<Field>(mesh.geometry_fields().get_child_checked("wall_distance"));
const auto& node_to_wall_element = *Handle<common::Table<Uint>>(mesh.get_child_checked("node_to_wall_element"));
const Real nu = physical_model().options().value<Real>("kinematic_viscosity");
for(Uint node_idx = 0; node_idx != nb_nodes; ++node_idx)
{
yplus_field[node_idx][0] = 0;
if(node_to_wall_element[node_idx][0] != 0)
{
const Entities& wall_entities = *wall_node_connectivity.entities()[node_to_wall_element[node_idx][1]];
const Uint wall_field_idx = wall_entities.space(wall_P0).connectivity()[node_to_wall_element[node_idx][2]][0];
yplus_field[node_idx][0] = wall_distance_field[node_idx][0] * sqrt(nu*wall_velocity_gradient_field[wall_field_idx][0]) / nu;
}
else
{
yplus_field[node_idx][0] = wall_distance_field[node_idx][0] * sqrt(nu*wall_velocity_gradient_field_nodal[node_to_wall_element[node_idx][1]][0]) / nu;
}
}
}
void SurfaceToVolumeConnectivity::execute()
{
Mesh& mesh = *m_mesh;
const Uint nb_nodes = mesh.geometry_fields().size();
if(mesh.get_child("volume_node_connectivity") != nullptr)
{
mesh.remove_component("volume_node_connectivity");
}
auto volume_node_connectivity = mesh.create_component<NodeConnectivity>("volume_node_connectivity");
std::vector< Handle<Entities const> > volume_entities;
for(const mesh::Elements& elements : common::find_components_recursively_with_filter<mesh::Elements>(mesh, IsElementsVolume()))
{
volume_entities.push_back(elements.handle<Entities const>());
}
volume_node_connectivity->initialize(nb_nodes, volume_entities);
for(mesh::Elements& wall_entity : common::find_components_recursively_with_filter<mesh::Elements>(mesh, IsElementsSurface()))
{
if(wall_entity.get_child("wall_face_connectivity") != nullptr)
{
wall_entity.remove_component("wall_face_connectivity");
}
wall_entity.create_component<FaceConnectivity>("wall_face_connectivity")->initialize(*volume_node_connectivity);
}
}