Blade mixing
Whole script
The code is a C++ implementation of a simulation using the netdem library. It sets up a simulation environment, including the simulation domain, contact model, shapes, walls, gravity, data dumping, and runs the simulation.
#include "data_dumper.hpp"
#include "gen_pack.hpp"
#include "gen_wall_box_plane.hpp"
#include "gravity.hpp"
#include "model_linear_spring.hpp"
#include "shape_cylinder.hpp"
#include "shape_sphere.hpp"
#include "shape_triangle.hpp"
#include "simulation.hpp"
#include <iostream>
#include <unordered_map>
using namespace netdem;
using namespace std;
void ImportWall(Simulation *sim) {
STLModel cylinder_stl;
cylinder_stl.InitFromSTL("data/cylinder.stl");
for (auto &vert : cylinder_stl.vertices) {
vert[2] *= 0.5;
}
cylinder_stl.SaveAsSTL("tmp/tests/cylinder_outer.stl");
for (auto &facet : cylinder_stl.facets) {
Triangle triangle(cylinder_stl.vertices[facet[0]],
cylinder_stl.vertices[facet[1]],
cylinder_stl.vertices[facet[2]]);
auto shape_ptr = sim->scene.InsertShape(&triangle);
Wall wall(shape_ptr);
sim->scene.InsertWall(wall);
}
for (auto &vert : cylinder_stl.vertices) {
vert[0] *= 0.15;
vert[1] *= 0.15;
vert[2] *= 0.64;
vert[2] -= 0.10;
}
cylinder_stl.SaveAsSTL("tmp/tests/cylinder_inner.stl");
for (auto &facet : cylinder_stl.facets) {
Triangle triangle(cylinder_stl.vertices[facet[0]],
cylinder_stl.vertices[facet[1]],
cylinder_stl.vertices[facet[2]]);
auto shape_ptr = sim->scene.InsertShape(&triangle);
Wall wall(shape_ptr);
sim->scene.InsertWall(wall);
}
STLModel propeller_stl;
propeller_stl.InitFromSTL("data/copyleft/propeller.stl");
propeller_stl.Standardize();
for (auto &vert : propeller_stl.vertices) {
vert[0] *= 0.14;
vert[1] *= 0.14;
vert[2] *= 0.8;
vert[2] -= 0.075;
}
propeller_stl.SaveAsSTL("tmp/tests/propeller.stl");
for (auto &facet : propeller_stl.facets) {
Triangle triangle(propeller_stl.vertices[facet[0]],
propeller_stl.vertices[facet[1]],
propeller_stl.vertices[facet[2]]);
triangle.skin *= 10.0;
auto shape_ptr = sim->scene.InsertShape(&triangle);
Wall wall;
wall.SetShape(shape_ptr, true);
wall.SetVelocitySpin(0, 0, -2.0 * Math::PI);
sim->scene.InsertWall(wall);
}
}
int main(int argc, char **argv) {
Simulation *sim = new Simulation();
sim->domain_manager.SetBound(-0.6, -0.6, -0.6, 0.6, 0.6, 0.6);
sim->domain_manager.SetCellSpacing(0.2, 0.2, 0.2);
LinearSpring cnt_model = LinearSpring(1.0e4, 1.0e4, 0.7, 0.5);
sim->scene.InsertContactModel(&cnt_model);
sim->scene.SetNumberOfMaterials(1);
sim->scene.SetCollisionModel(0, 0, cnt_model.label);
Sphere sphere = Sphere(0.02);
sphere.skin *= 1.0;
auto shape_ptr = sim->scene.InsertShape(&sphere);
VecXT<Particle> particle_list = PackGenerator::GetGridPack(
0.7, 0.7, 0.1, 0, 0, 0.2, 25, 20, 2, sim->scene.GetShapes());
for (auto &p : particle_list) {
p.SetVelocity(0, 0, -2.0);
}
ImportWall(sim);
Gravity grav;
grav.Init(sim);
sim->modifier_manager.Insert(&grav);
sim->modifier_manager.Enable(grav.label);
DataDumper data_dumper;
data_dumper.Init(sim);
data_dumper.SetRootPath("tmp/out/");
data_dumper.SetSaveByCycles(100);
data_dumper.dump_wall_info = true;
data_dumper.dump_shape_info = true;
sim->modifier_manager.Insert(&data_dumper);
sim->modifier_manager.Enable(data_dumper.label);
for (int i = 0; i < 20; i++) {
sim->scene.InsertParticle(particle_list);
sim->Run(0.1);
}
sim->Run(2.0);
delete sim;
}
Step-by-step explaination
Here's a breakdown of the code:
void ImportWall(Simulation *sim) {
// ...
}
This function defines the ImportWall function, which is used to import wall shapes into the simulation. The walls are created based on STL models and inserted into the simulation scene.
int main(int argc, char **argv) {
Simulation *sim = new Simulation();
The main function initializes a new Simulation object and assigns it to the sim pointer.
sim->domain_manager.SetBound(-0.6, -0.6, -0.6, 0.6, 0.6, 0.6);
sim->domain_manager.SetCellSpacing(0.2, 0.2, 0.2);
The boundary and cell spacing of the simulation domain are set using the methods SetBound and SetCellSpacing of the domain_manager object.
LinearSpring cnt_model = LinearSpring(1.0e4, 1.0e4, 0.7, 0.5);
sim->scene.InsertContactModel(&cnt_model);
sim->scene.SetNumberOfMaterials(1);
sim->scene.SetCollisionModel(0, 0, cnt_model.label);
A linear spring contact model is created and inserted into the simulation scene using the InsertContactModel method of the scene object. The number of materials in the scene is set to 1, and the collision model at index 0 is updated with the label of the contact model.
Sphere sphere = Sphere(0.02);
sphere.skin *= 1.0;
auto shape_ptr = sim->scene.InsertShape(&sphere);
A sphere shape is created and inserted into the simulation scene using the InsertShape method of the scene object. The sphere's skin (radius) is adjusted, and the resulting shape pointer is stored for later use.
VecXT<Particle> particle_list = PackGenerator::GetGridPack(
0.7, 0.7, 0.1, 0, 0, 0.2, 25, 20, 2, sim->scene.GetShapes());
for (auto &p : particle_list) {
p.SetVelocity(0, 0, -2.0);
}
A grid-based particle pack is generated using the GetGridPack method of the PackGenerator class. The parameters provided determine the position, size, and layout of the particles in the grid. The initial velocity of each particle in the pack is set to move downward.
ImportWall(sim);
The ImportWall function is called to import wall shapes into the simulation.
Gravity grav;
grav.Init(sim);
sim->modifier_manager.Insert(&grav);
sim->modifier_manager.Enable(grav.label);
A gravity modifier is created, initialized with the simulation object, inserted into the modifier manager, and enabled.
DataDumper data_dumper;
data_dumper.Init(sim);
data_dumper.SetRootPath("tmp/out/");
data_dumper.SetSaveByCycles(100);
data_dumper.dump_wall_info = true;
data_dumper.dump_shape_info = true;
sim->modifier_manager.Insert(&data_dumper);
sim->modifier_manager.Enable(data_dumper.label);
A data dumper object is created, initialized with the simulation object, and configured to save data by cycles. The root path for saving files is set, and options for dumping wall and shape information are enabled. The data dumper object is then inserted into the modifier manager and enabled.
for (int i = 0; i < 20; i++) {
sim->scene.InsertParticle(particle_list);
sim->Run(0.1);
}
sim->Run(2.0);
delete sim;
}
A loop is used to insert particles from the particle list into the simulation scene, and the simulation is run for a duration of 0.1 time units. This loop allows the particles to settle in the simulation before further simulation steps. After the loop, the simulation is run for an additional 2.0 time units. Finally, the sim pointer is deleted to free the memory.