/* ---------------------------------------------------------------------- This is the ██╗ ██╗ ██████╗ ██████╗ ██████╗ ██╗ ██╗████████╗███████╗ ██║ ██║██╔════╝ ██╔════╝ ██╔════╝ ██║ ██║╚══██╔══╝██╔════╝ ██║ ██║██║ ███╗██║ ███╗██║ ███╗███████║ ██║ ███████╗ ██║ ██║██║ ██║██║ ██║██║ ██║██╔══██║ ██║ ╚════██║ ███████╗██║╚██████╔╝╚██████╔╝╚██████╔╝██║ ██║ ██║ ███████║ ╚══════╝╚═╝ ╚═════╝ ╚═════╝ ╚═════╝ ╚═╝ ╚═╝ ╚═╝ ╚══════╝® DEM simulation engine, released by DCS Computing Gmbh, Linz, Austria http://www.dcs-computing.com, office@dcs-computing.com LIGGGHTS® is part of CFDEM®project: http://www.liggghts.com | http://www.cfdem.com Core developer and main author: Christoph Kloss, christoph.kloss@dcs-computing.com LIGGGHTS® is open-source, distributed under the terms of the GNU Public License, version 2 or later. It is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. You should have received a copy of the GNU General Public License along with LIGGGHTS®. If not, see http://www.gnu.org/licenses . See also top-level README and LICENSE files. LIGGGHTS® and CFDEM® are registered trade marks of DCS Computing GmbH, the producer of the LIGGGHTS® software and the CFDEM®coupling software See http://www.cfdem.com/terms-trademark-policy for details. ------------------------------------------------------------------------- Contributing author and copyright for this file: Christoph Kloss (DCS Computing GmbH, Linz) Christoph Kloss (JKU Linz) Richard Berger (JKU Linz) Copyright 2012- DCS Computing GmbH, Linz Copyright 2009-2012 JKU Linz ------------------------------------------------------------------------- */ #ifdef TANGENTIAL_MODEL TANGENTIAL_MODEL(TANGENTIAL_HISTORY,history,2) #else #ifndef TANGENTIAL_MODEL_HISTORY_H_ #define TANGENTIAL_MODEL_HISTORY_H_ #include "contact_models.h" #include "math.h" #include "update.h" #include "global_properties.h" #include "atom.h" #include namespace LIGGGHTS { namespace ContactModels { template<> class TangentialModel : protected Pointers { double ** coeffFrict; int history_offset; int history_offset2; public: static const int MASK = CM_CONNECT_TO_PROPERTIES | CM_SURFACES_INTERSECT | CM_SURFACES_CLOSE; TangentialModel(LAMMPS * lmp, IContactHistorySetup * hsetup,class ContactModelBase *c) : Pointers(lmp), coeffFrict(NULL), heating(false), heating_track(false), cmb(c) { history_offset = hsetup->add_history_value("shearx", "1"); hsetup->add_history_value("sheary", "1"); hsetup->add_history_value("shearz", "1"); history_offset2 = hsetup->add_history_value("dissVal", "0"); } inline void registerSettings(Settings& settings) { settings.registerOnOff("heating_tangential_history",heating,false); settings.registerOnOff("heating_tracking",heating_track,false); //TODO error->one(FLERR,"TODO here also check if right surface model used"); } inline void connectToProperties(PropertyRegistry & registry) { registry.registerProperty("coeffFrict", &MODEL_PARAMS::createCoeffFrict); registry.connect("coeffFrict", coeffFrict,"tangential_model history"); } inline void surfacesIntersect(const SurfacesIntersectData & sidata, ForceData & i_forces, ForceData & j_forces) { // normal forces = Hookian contact + normal velocity damping const double enx = sidata.en[0]; const double eny = sidata.en[1]; const double enz = sidata.en[2]; double * const dissValex = &sidata.contact_history[history_offset2]; // save previous diss value double dissPrev; dissPrev = dissValex[0]; // shear history effects if(sidata.contact_flags) *sidata.contact_flags |= CONTACT_TANGENTIAL_MODEL; double * const shear = &sidata.contact_history[history_offset]; if (sidata.shearupdate && sidata.computeflag) { const double dt = update->dt; shear[0] += sidata.vtr1 * dt; shear[1] += sidata.vtr2 * dt; shear[2] += sidata.vtr3 * dt; // rotate shear displacements double rsht = shear[0]*enx + shear[1]*eny + shear[2]*enz; shear[0] -= rsht * enx; shear[1] -= rsht * eny; shear[2] -= rsht * enz; } const double shrmag = sqrt(shear[0]*shear[0] + shear[1]*shear[1] + shear[2]*shear[2]); const double kt = sidata.kt; const double xmu = coeffFrict[sidata.itype][sidata.jtype]; // tangential forces = shear + tangential velocity damping double Ft1 = -(kt * shear[0]); double Ft2 = -(kt * shear[1]); double Ft3 = -(kt * shear[2]); // rescale frictional displacements and forces if needed const double Ft_shear = kt * shrmag; // sqrt(Ft1 * Ft1 + Ft2 * Ft2 + Ft3 * Ft3); const double Ft_friction = xmu * fabs(sidata.Fn); // energy loss from sliding or damping if (Ft_shear > Ft_friction) { if (shrmag != 0.0) { const double ratio = Ft_friction / Ft_shear; if(heating) { sidata.P_diss += (vectorMag3DSquared(shear)*kt - ratio*ratio*vectorMag3DSquared(shear)*kt) / (update->dt); if(heating_track && sidata.is_wall) cmb->tally_pw((vectorMag3DSquared(shear)*kt - ratio*ratio*vectorMag3DSquared(shear)*kt) / (update->dt),sidata.i,sidata.jtype,2); if(heating_track && !sidata.is_wall) cmb->tally_pp((vectorMag3DSquared(shear)*kt - ratio*ratio*vectorMag3DSquared(shear)*kt) / (update->dt),sidata.i,sidata.j,2); } Ft1 *= ratio; Ft2 *= ratio; Ft3 *= ratio; const double inelastic1 = shear[0]-(-Ft1/kt); const double inelastic2 = shear[1]-(-Ft2/kt); const double inelastic3 = shear[2]-(-Ft3/kt); dissValex[0] = Ft1*inelastic1 + Ft2*inelastic2 + Ft3*inelastic3 + dissPrev; std::cout << "\nDEBUG: IN IF LOOP!!!!\n"; //sidata.diss += Ft1*inelastic1 + Ft2*inelastic2 + Ft3*inelastic3; sidata.diss = dissValex[0]; std::cout << "\nDEBUG: Ft = " << Ft1 << " " << Ft2 << " " << Ft3 << "\n" ; std::cout << "\nDEBUG: shear = " << shear[0] << " " << shear[1] << " " << shear[2] << "\n" ; std::cout << "\nDEBUG: inelastic = " << inelastic1 << " " << inelastic2 << " " << inelastic3 << "\n" ; std::cout << "\nDEBUG: sidata.diss = " << sidata.diss << "\n" ; if (sidata.shearupdate && sidata.computeflag) { shear[0] = -Ft1/kt; shear[1] = -Ft2/kt; shear[2] = -Ft3/kt; } } else Ft1 = Ft2 = Ft3 = 0.0; } else { const double gammat = sidata.gammat; Ft1 -= (gammat*sidata.vtr1); Ft2 -= (gammat*sidata.vtr2); Ft3 -= (gammat*sidata.vtr3); if(heating) { sidata.P_diss += gammat*(sidata.vtr1*sidata.vtr1+sidata.vtr2*sidata.vtr2+sidata.vtr3*sidata.vtr3); if(heating_track && sidata.is_wall) cmb->tally_pw(gammat*(sidata.vtr1*sidata.vtr1+sidata.vtr2*sidata.vtr2+sidata.vtr3*sidata.vtr3),sidata.i,sidata.jtype,1); if(heating_track && !sidata.is_wall) cmb->tally_pp(gammat*(sidata.vtr1*sidata.vtr1+sidata.vtr2*sidata.vtr2+sidata.vtr3*sidata.vtr3),sidata.i,sidata.j,1); } } // forces & torques const double tor1 = eny * Ft3 - enz * Ft2; const double tor2 = enz * Ft1 - enx * Ft3; const double tor3 = enx * Ft2 - eny * Ft1; #ifdef SUPERQUADRIC_ACTIVE_FLAG double torque_i[3]; if(sidata.is_non_spherical) { double xci[3]; double Ft_i[3] = { Ft1, Ft2, Ft3 }; vectorSubtract3D(sidata.contact_point, sidata.pos_i, xci); vectorCross3D(xci, Ft_i, torque_i); } else { torque_i[0] = -sidata.cri * tor1; torque_i[1] = -sidata.cri * tor2; torque_i[2] = -sidata.cri * tor3; } #endif // return resulting forces if(sidata.is_wall) { const double area_ratio = sidata.area_ratio; i_forces.delta_F[0] += Ft1 * area_ratio; i_forces.delta_F[1] += Ft2 * area_ratio; i_forces.delta_F[2] += Ft3 * area_ratio; #ifdef SUPERQUADRIC_ACTIVE_FLAG i_forces.delta_torque[0] += torque_i[0] * area_ratio; i_forces.delta_torque[1] += torque_i[1] * area_ratio; i_forces.delta_torque[2] += torque_i[2] * area_ratio; #else i_forces.delta_torque[0] = -sidata.cri * tor1 * area_ratio; i_forces.delta_torque[1] = -sidata.cri * tor2 * area_ratio; i_forces.delta_torque[2] = -sidata.cri * tor3 * area_ratio; #endif } else { i_forces.delta_F[0] += Ft1; i_forces.delta_F[1] += Ft2; i_forces.delta_F[2] += Ft3; j_forces.delta_F[0] += -Ft1; j_forces.delta_F[1] += -Ft2; j_forces.delta_F[2] += -Ft3; #ifdef SUPERQUADRIC_ACTIVE_FLAG double torque_j[3]; if(sidata.is_non_spherical) { double xcj[3]; vectorSubtract3D(sidata.contact_point, sidata.pos_j, xcj); double Ft_j[3] = { -Ft1, -Ft2, -Ft3 }; vectorCross3D(xcj, Ft_j, torque_j); } else { torque_j[0] = -sidata.crj * tor1; torque_j[1] = -sidata.crj * tor2; torque_j[2] = -sidata.crj * tor3; } i_forces.delta_torque[0] += torque_i[0]; i_forces.delta_torque[1] += torque_i[1]; i_forces.delta_torque[2] += torque_i[2]; j_forces.delta_torque[0] += torque_j[0]; j_forces.delta_torque[1] += torque_j[1]; j_forces.delta_torque[2] += torque_j[2]; #else i_forces.delta_torque[0] = -sidata.cri * tor1; i_forces.delta_torque[1] = -sidata.cri * tor2; i_forces.delta_torque[2] = -sidata.cri * tor3; j_forces.delta_torque[0] = -sidata.crj * tor1; j_forces.delta_torque[1] = -sidata.crj * tor2; j_forces.delta_torque[2] = -sidata.crj * tor3; #endif } } inline void surfacesClose(SurfacesCloseData & scdata, ForceData&, ForceData&) { // unset non-touching neighbors // TODO even if shearupdate == false? if(scdata.contact_flags) *scdata.contact_flags &= ~CONTACT_TANGENTIAL_MODEL; double * const shear = &scdata.contact_history[history_offset]; shear[0] = 0.0; shear[1] = 0.0; shear[2] = 0.0; } inline void beginPass(SurfacesIntersectData&, ForceData&, ForceData&){} inline void endPass(SurfacesIntersectData&, ForceData&, ForceData&){} protected: bool heating; bool heating_track; class ContactModelBase *cmb; }; } } #endif // TANGENTIAL_MODEL_HISTORY_H_ #endif