GranularCollapseDemo.cpp File Reference

#include <iostream>
#include "Mercury3D.h"
#include "Species/HertzianViscoelasticMindlinSpecies.h"
#include "Walls/InfiniteWall.h"

Classes
class	GranularCollapse

Functions
int	main (int argc, char *argv[])

Function Documentation

main()

int main	(	int argc	,
		char *	argv[]
	)

{
    GranularCollapse problem;
    problem.setName("granular_collapse_sqellipsoids");
    logger(INFO, "Modified from 'MercurySimpleDemos/InsertionBoundarySelfTest.cpp'");
    
    // [GranularCollapse : particle properties]
    problem.species->setDensity(950); // 2000;
    
    double input1 = 50; //1000; // 500; 1000; 15500;
    double input2 = 1.5; // magnifying scale (geq 1)
    if (argc > 1)
    {
        input1 = atof(argv[1]);
        input2 = atof(argv[2]);
    }
    problem.nMax = input1;
    problem.radScale = input2;
    logger(INFO, "Number of particles = %\n"
                 "Half-length scale = %", problem.nMax, problem.radScale);
    
    problem.radMax = 5.e-3; //1.e-3; 4.5e-3; 4.e-3
    problem.radMin = problem.radMax / problem.radScale / std::sqrt(problem.radScale);
    // [GranularCollapse : particle properties]
    
    // [GranularCollapse : contact properties]
    problem.species->setEffectiveElasticModulusAndRestitutionCoefficient(1.e7, 0.7); //1.e5
//    //normal forces
//    problem.species->setStiffness(2e4); //1e5; 2e4; 8e3; 1e4
//    problem.species->setDissipation(0.5); //0.5; 0.25; 0.3; dissipation <= sqrt(2*stiffness*MinParticleMass) to avoid overdamping
//    //tangential forces : sliding
//    problem.species->setSlidingFrictionCoefficient(0.5);
//    problem.species->setSlidingStiffness(problem.species->getStiffness()*0.2);
//    problem.species->setSlidingDissipation(problem.species->getDissipation()*0.2);
//    //normal torques : spin
//    problem.species->setTorsionFrictionCoefficient(problem.species->getSlidingFrictionCoefficient()*0.05);
//    problem.species->setTorsionStiffness(problem.species->getStiffness()*0.1);
//    problem.species->setTorsionDissipation(problem.species->getDissipation()*0.05);
//    //tangential torques : rolling
//    problem.species->setRollingFrictionCoefficient(problem.species->getSlidingFrictionCoefficient()*0.05);
//    problem.species->setRollingStiffness(problem.species->getStiffness()*0.1);
//    problem.species->setRollingDissipation(problem.species->getDissipation()*0.05);
    // [GranularCollapse : contact properties]
    
    // [GranularCollapse : test normal forces]
    //(from 'MercurySimpleDemos/HourGlass3DDemo.cpp')
    //Calculates collision time for two copies of a particle of given dissipation_, k, effective mass
    double MinParticleMass = problem.species->getDensity() * 4. / 3. * constants::pi * mathsFunc::cubic(problem.radMin);
    logger(INFO, "MinParticleMass = %%3\n", std::scientific, MinParticleMass, Flusher::NO_FLUSH);
    //Calculates collision time for two copies of a particle of given dissipation_, k, effective mass
    double tc = problem.species->getCollisionTime(2 * problem.radMin, problem.species->getDensity(), 1.0);
    logger(INFO, "tc = %%", tc, std::defaultfloat);
//    //Calculates restitution coefficient for two copies of given dissipation_, k, effective mass
//    double r = problem.species->getRestitutionCoefficient(MinParticleMass);
//    std::cout << "r = " << r << std::endl;
    //Calculates the maximum relative velocity allowed for a normal collision of two particles of radius r and particle mass m (for higher velocities particles could pass through each other)
    //std::cout << "vmax=" << helpers::getMaximumVelocity(species->getStiffness(), HGgetSpecies(0)->getDissipation(), HG.MinParticleRadius, MinParticleMass) << std::endl;
    // [GranularCollapse : test normal forces]
    
    // [GranularCollapse : time parameters]
    problem.setTimeStep(tc / 50); // 1e-4; // (tc / 50);
    problem.setTimeMax(2.5); //5; //15;
    problem.openGate = .7 * problem.getTimeMax();
    problem.setSaveCount(500);
    // [GranularCollapse : time parameters]
    
    // [GranularCollapse : contact detection]
    problem.setHGridMaxLevels(2);
    // [GranularCollapse : contact detection]
    
    problem.setSuperquadricParticlesWriteVTK(true);
    problem.wallHandler.setWriteVTK(FileType::ONE_FILE);
    problem.solve(); //argc,argv
    return 0;
} // [GranularCollapse : main]

References mathsFunc::cubic(), INFO, logger, NO_FLUSH, ONE_FILE, constants::pi, problem, and sqrt().