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#ifdef YADE_SPH
#include "SPHEngine.hpp"
#include <core/Scene.hpp>
#include <pkg/common/Sphere.hpp>
#include <pkg/dem/ViscoelasticPM.hpp>
#include <core/Omega.hpp>
#include <core/State.hpp>
namespace yade { // Cannot have #include directive inside.
void SPHEngine::action()
{
{
YADE_PARALLEL_FOREACH_BODY_BEGIN(const shared_ptr<Body>& b, scene->bodies)
{
if (mask > 0 && (b->groupMask & mask) == 0) continue;
this->calculateSPHRho(b);
b->state->press = math::max(0.0, k * (b->state->rho - b->state->rho0));
}
YADE_PARALLEL_FOREACH_BODY_END();
}
}
void SPHEngine::calculateSPHRho(const shared_ptr<Body>& b)
{
if (b->state->rho0 < 0) { b->state->rho0 = rho0; }
if (not b->isClump()) {
Real rho = 0;
// Pointer to kernel function
KernelFunction kernelFunctionCurDensity = returnKernelFunction(KernFunctionDensity, Norm);
// Calculate rho for every particle
for (Body::MapId2IntrT::iterator it = b->intrs.begin(), end = b->intrs.end(); it != end; ++it) {
const shared_ptr<Body> b2 = Body::byId((*it).first, scene);
Sphere* s = dynamic_cast<Sphere*>(b->shape.get());
if (!s) continue;
if (((*it).second)->geom and ((*it).second)->phys) {
const ScGeom geom = *(YADE_PTR_CAST<ScGeom>(((*it).second)->geom));
const ViscElPhys phys = *(YADE_PTR_CAST<ViscElPhys>(((*it).second)->phys));
Real Mass = b2->state->mass;
if (Mass == 0) Mass = b->state->mass;
const Real SmoothDist = (b2->state->pos - b->state->pos).norm();
// [Monaghan1992], (2.7) (3.8)
rho += b2->state->mass * kernelFunctionCurDensity(SmoothDist, h);
}
}
// Self mass contribution
rho += b->state->mass * kernelFunctionCurDensity(0.0, h);
b->state->rho = rho;
}
}
Real smoothkernelLucy(const double& r, const double& h)
{
if (r <= h && h > 0) {
// Lucy Kernel function, [Lucy1977] (27)
const Real r_h = r / h;
return 105. / (16. * M_PI * h * h * h) * (1. + 3. * r_h) * math::pow((1. - r_h), 3);
} else {
return 0;
}
}
Real smoothkernelLucyGrad(const double& r, const double& h)
{
if (r <= h && h > 0) {
// 1st derivative of Lucy Kernel function, [Lucy1977] (27)
return 105. / (16. * M_PI * h * h * h) * (-12. * r) * math::pow((h - r), 2) / (h * h * h * h);
} else {
return 0;
}
}
Real smoothkernelLucyLapl(const double& r, const double& h)
{
if (r <= h && h > 0) {
// 2nd derivative of Lucy Kernel function, [Lucy1977] (27)
return 105. / (16. * M_PI * h * h * h) * (-12.) / (h * h * h * h) * (h * h - 2. * r * h + 3. * r * r);
} else {
return 0;
}
}
//=========================================================================
Real smoothkernelBSpline1(const double& r, const double& h)
{
// BSpline Kernel function, [Monaghan1985] (21)
if (r <= 2.0 * h && h > 0) {
const Real coefA = 3. / (2. * M_PI * h * h * h);
const Real r_h = r / h;
if (r <= h) {
return coefA * (2. / 3. - r_h * r_h + 1. / 2. * r_h * r_h * r_h);
} else {
return coefA / 6. * math::pow((2. - r_h), 3);
}
} else {
return 0;
}
}
Real smoothkernelBSpline1Grad(const double& r, const double& h)
{
// 1st derivative of BSpline Kernel function, [Monaghan1985] (21)
if (r <= 2. * h && h > 0) {
const Real coefA = 3. / (2. * M_PI * h * h * h);
const Real r_h = r / h;
if (r <= h) {
return coefA * (-r_h) * (2. - 3. / 2. * r_h);
} else {
return coefA * (-1. / 2.) * math::pow((2. - r_h), 2);
}
} else {
return 0;
}
}
Real smoothkernelBSpline1Lapl(const double& r, const double& h)
{
// 2nd derivative of BSpline Kernel function, [Monaghan1985] (21)
if (r <= 2.0 * h && h > 0) {
const Real coefA = 3. / (2. * M_PI * h * h * h);
const Real r_h = r / h;
if (r <= h) {
return coefA * (-2. + 3. * r_h);
} else {
return coefA * (2. - r_h);
}
} else {
return 0;
}
}
//=========================================================================
Real smoothkernelBSpline2(const double& r, const double& h)
{
// BSpline Kernel function, [Monaghan1985] (22)
if (r <= 2.0 * h && h > 0) {
const Real coefA = 3. / (4. * M_PI * h * h * h);
const Real r_h = r / h;
if (r <= h) {
return coefA * (10. / 3. - 7. * r_h * r_h + 4 * r_h * r_h * r_h);
} else {
return coefA * math::pow((2. - r_h), 2) * ((5. - 4. * r_h) / 3.);
}
} else {
return 0;
}
}
Real smoothkernelBSpline2Grad(const double& r, const double& h)
{
// 1st derivative of BSpline Kernel function, [Monaghan1985] (22)
if (r <= 2.0 * h && h > 0) {
const Real coefA = 3. / (4. * M_PI * h * h * h);
const Real r_h = r / h;
if (r <= h) {
return coefA * (-2.) / (h * h) * (7. * r - 6. * r * r_h);
} else {
return coefA * 2. / h * (-6. + 7. * r_h - 2. * math::pow(r_h, 2));
}
} else {
return 0;
}
}
Real smoothkernelBSpline2Lapl(const double& r, const double& h)
{
// 2nd derivative of BSpline Kernel function, [Monaghan1985] (22)
if (r <= 2.0 * h && h > 0) {
const Real coefA = 3. / (4. * M_PI * h * h * h);
const Real r_h = r / h;
if (r <= h) {
return coefA * (-2.) / (h * h) * (7. - 12. * r_h);
} else {
return coefA * 2. / (h * h) * (7. - 4. * r_h);
}
} else {
return 0;
}
}
//=========================================================================
KernelFunction returnKernelFunction(const int a, const typeKernFunctions typeF) { return returnKernelFunction(a, a, typeF); }
KernelFunction returnKernelFunction(const int a, const int b, const typeKernFunctions typeF)
{
if (a != b) { throw runtime_error("Kernel types should be equal!"); }
if (a == Lucy) {
if (typeF == Norm) {
return smoothkernelLucy;
} else if (typeF == Grad) {
return smoothkernelLucyGrad;
} else if (typeF == Lapl) {
return smoothkernelLucyLapl;
} else {
KERNELFUNCDESCR
}
} else if (a == BSpline1) {
if (typeF == Norm) {
return smoothkernelBSpline1;
} else if (typeF == Grad) {
return smoothkernelBSpline1Grad;
} else if (typeF == Lapl) {
return smoothkernelBSpline1Lapl;
} else {
KERNELFUNCDESCR
}
} else if (a == BSpline2) {
if (typeF == Norm) {
return smoothkernelBSpline2;
} else if (typeF == Grad) {
return smoothkernelBSpline2Grad;
} else if (typeF == Lapl) {
return smoothkernelBSpline2Lapl;
} else {
KERNELFUNCDESCR
}
} else {
KERNELFUNCDESCR
}
}
bool computeForceSPH(shared_ptr<IGeom>& _geom, shared_ptr<IPhys>& _phys, Interaction* I, Vector3r& force)
{
const ScGeom& geom = *static_cast<ScGeom*>(_geom.get());
Scene* scene = Omega::instance().getScene().get();
ViscElPhys& phys = *static_cast<ViscElPhys*>(_phys.get());
const int id1 = I->getId1();
const int id2 = I->getId2();
const BodyContainer& bodies = *scene->bodies;
if (bodies[id1]->isClumpMember() and bodies[id2]->isClumpMember() and bodies[id1]->clumpId == bodies[id2]->clumpId) {
//If 2 bodies belong to the same clump, do not calculate forces
force = Vector3r::Zero();
return true;
}
//////////////////////////////////////////////////////////////////
// Copy-paste
// Handle periodicity.
const Vector3r shift2 = scene->isPeriodic ? scene->cell->intrShiftPos(I->cellDist) : Vector3r::Zero();
const Vector3r shiftVel = scene->isPeriodic ? scene->cell->intrShiftVel(I->cellDist) : Vector3r::Zero();
const State& de1 = *static_cast<State*>(bodies[id1]->state.get());
const State& de2 = *static_cast<State*>(bodies[id2]->state.get());
const Vector3r c1x = (geom.contactPoint - de1.pos);
const Vector3r c2x = (geom.contactPoint - de2.pos - shift2);
const Vector3r relativeVelocity = (de1.vel + de1.angVel.cross(c1x)) - (de2.vel + de2.angVel.cross(c2x)) + shiftVel;
const Real normalVelocity = geom.normal.dot(relativeVelocity);
// Copy-paste
//////////////////////////////////////////////////////////////////
const Real Mass1 = bodies[id1]->state->mass;
const Real Mass2 = bodies[id2]->state->mass;
const Real Rho1 = bodies[id1]->state->rho;
const Real Rho2 = bodies[id2]->state->rho;
const Vector3r xixj = de2.pos - de1.pos;
if (phys.kernelFunctionCurrentPressure(xixj.norm(), phys.h)) {
Real fpressure = 0.0;
if (Rho1 != 0.0 and Rho2 != 0.0) {
// from [Monaghan1992], (3.3), multiply by Mass2, because we need a force, not du/dt
fpressure = -Mass1 * Mass2 * (bodies[id1]->state->press / (Rho1 * Rho1) + bodies[id2]->state->press / (Rho2 * Rho2))
* phys.kernelFunctionCurrentPressure(xixj.norm(), phys.h);
}
Vector3r fvisc = Vector3r::Zero();
if (Rho1 != 0.0 and Rho2 != 0.0) {
// from [Morris1997], (22), multiply by Mass2, because we need a force, not du/dt
fvisc = phys.mu * Mass1 * Mass2 * (-normalVelocity * geom.normal) / (Rho1 * Rho2) * 1 / (xixj.norm())
* phys.kernelFunctionCurrentPressure(xixj.norm(), phys.h);
//phys.kernelFunctionCurrentVisco(xixj.norm(), phys.h);
}
force = fpressure * geom.normal + fvisc;
return true;
} else {
return false;
}
}
YADE_PLUGIN((SPHEngine));
} // namespace yade
#endif
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