lammps-sys 0.6.0

Generates bindings to LAMMPS' C interface (with optional builds from source)
Documentation
/* -*- c++ -*- ----------------------------------------------------------
 *
 *                    *** Smooth Mach Dynamics ***
 *
 * This file is part of the USER-SMD package for LAMMPS.
 * Copyright (2014) Georg C. Ganzenmueller, georg.ganzenmueller@emi.fhg.de
 * Fraunhofer Ernst-Mach Institute for High-Speed Dynamics, EMI,
 * Eckerstrasse 4, D-79104 Freiburg i.Br, Germany.
 *
 * ----------------------------------------------------------------------- */

/* ----------------------------------------------------------------------
 LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator
 http://lammps.sandia.gov, Sandia National Laboratories
 Steve Plimpton, sjplimp@sandia.gov

 Copyright (2003) Sandia Corporation.  Under the terms of Contract
 DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government retains
 certain rights in this software.  This software is distributed under
 the GNU General Public License.

 See the README file in the top-level LAMMPS directory.
 ------------------------------------------------------------------------- */

#ifdef PAIR_CLASS

PairStyle(smd/tlsph,PairTlsph)

#else

#ifndef LMP_TLSPH_NEW_H
#define LMP_TLSPH_NEW_H

#include "pair.h"
#include <Eigen/Eigen>

namespace LAMMPS_NS {

class PairTlsph: public Pair {
public:

        PairTlsph(class LAMMPS *);
        virtual ~PairTlsph();
        virtual void compute(int, int);
        void settings(int, char **);
        void coeff(int, char **);
        double init_one(int, int);
        void init_style();
        void init_list(int, class NeighList *);
        void write_restart_settings(FILE *) {
        }
        void read_restart_settings(FILE *) {
        }
        virtual double memory_usage();
        void compute_shape_matrix(void);
        void material_model(void);
        void *extract(const char *, int &);
        int pack_forward_comm(int, int *, double *, int, int *);
        void unpack_forward_comm(int, int, double *);
        void AssembleStress();

        void PreCompute();
        void ComputeForces(int eflag, int vflag);
        void effective_longitudinal_modulus(const int itype, const double dt, const double d_iso, const double p_rate,
                        const Eigen::Matrix3d d_dev, const Eigen::Matrix3d sigma_dev_rate, const double damage, double &K_eff, double &mu_eff, double &M_eff);

        void ComputePressure(const int i, const double rho, const double mass_specific_energy, const double vol_specific_energy,
                        const double pInitial, const double d_iso, double &pFinal, double &p_rate);
        void ComputeStressDeviator(const int i, const Eigen::Matrix3d sigmaInitial_dev, const Eigen::Matrix3d d_dev, Eigen::Matrix3d &sigmaFinal_dev,
                        Eigen::Matrix3d &sigma_dev_rate, double &plastic_strain_increment);
        void ComputeDamage(const int i, const Eigen::Matrix3d strain, const Eigen::Matrix3d sigmaFinal, Eigen::Matrix3d &sigma_damaged);


protected:
        void allocate();
        char *suffix;

        /*
         * per-type arrays
         */
        int *strengthModel, *eos;
        double *onerad_dynamic, *onerad_frozen, *maxrad_dynamic, *maxrad_frozen;

        /*
         * per atom arrays
         */
        Eigen::Matrix3d *K, *PK1, *Fdot, *Fincr;
        Eigen::Matrix3d *R; // rotation matrix
        Eigen::Matrix3d *FincrInv;
        Eigen::Matrix3d *D, *W; // strain rate and spin tensor
        Eigen::Vector3d *smoothVelDifference;
        Eigen::Matrix3d *CauchyStress;
        double *detF, *particle_dt;
        double *hourglass_error;
        int *numNeighsRefConfig;

        int nmax; // max number of atoms on this proc
        double hMin; // minimum kernel radius for two particles
        double dtCFL;
        double dtRelative; // relative velocity of two particles, divided by sound speed
        int updateFlag;
        double update_threshold; // updateFlage is set to one if the relative displacement of a pair exceeds update_threshold
        double cut_comm;

        enum {
                UPDATE_NONE = 5000, UPDATE_CONSTANT_THRESHOLD = 5001, UPDATE_PAIRWISE_RATIO = 5002,
        };

        enum {
                LINEAR_DEFGRAD = 0,
                STRENGTH_LINEAR = 1,
                STRENGTH_LINEAR_PLASTIC = 2,
                STRENGTH_JOHNSON_COOK = 3,
                STRENGTH_NONE = 4,
                EOS_LINEAR = 5,
                EOS_SHOCK = 6,
                EOS_POLYNOMIAL = 7,
                EOS_NONE = 8,
                REFERENCE_DENSITY = 9,
                YOUNGS_MODULUS = 10,
                POISSON_RATIO = 11,
                HOURGLASS_CONTROL_AMPLITUDE = 12,
                HEAT_CAPACITY = 13,
                LAME_LAMBDA = 14,
                SHEAR_MODULUS = 15,
                M_MODULUS = 16,
                SIGNAL_VELOCITY = 17,
                BULK_MODULUS = 18,
                VISCOSITY_Q1 = 19,
                VISCOSITY_Q2 = 20,
                YIELD_STRESS = 21,
                FAILURE_MAX_PLASTIC_STRAIN_THRESHOLD = 22,
                JC_A = 23,
                JC_B = 24,
                JC_a = 25,
                JC_C = 26,
                JC_epdot0 = 27,
                JC_T0 = 28,
                JC_Tmelt = 29,
                JC_M = 30,
                EOS_SHOCK_C0 = 31,
                EOS_SHOCK_S = 32,
                EOS_SHOCK_GAMMA = 33,
                HARDENING_PARAMETER = 34,
                FAILURE_MAX_PRINCIPAL_STRAIN_THRESHOLD = 35,
                FAILURE_MAX_PRINCIPAL_STRESS_THRESHOLD = 36,
                FAILURE_MAX_PAIRWISE_STRAIN_THRESHOLD = 37,
                EOS_POLYNOMIAL_C0 = 38,
                EOS_POLYNOMIAL_C1 = 39,
                EOS_POLYNOMIAL_C2 = 40,
                EOS_POLYNOMIAL_C3 = 41,
                EOS_POLYNOMIAL_C4 = 42,
                EOS_POLYNOMIAL_C5 = 43,
                EOS_POLYNOMIAL_C6 = 44,

                FAILURE_JC_D1 = 45,
                FAILURE_JC_D2 = 46,
                FAILURE_JC_D3 = 47,
                FAILURE_JC_D4 = 48,
                FAILURE_JC_EPDOT0 = 49,

                CRITICAL_ENERGY_RELEASE_RATE = 50,

                MAX_KEY_VALUE = 51
        };

        struct failure_types { // this is defined per type and determines which failure/damage model is active
                bool failure_none;
                bool failure_max_principal_strain;
                bool failure_max_principal_stress;
                bool failure_max_plastic_strain;
                bool failure_johnson_cook;
                bool failure_max_pairwise_strain;
                bool integration_point_wise; // true if failure model applies to stress/strain state of integration point
                bool failure_energy_release_rate;

                failure_types() {
                        failure_none = true;
                        failure_max_principal_strain = false;
                        failure_max_principal_stress = false;
                        failure_max_plastic_strain = false;
                        failure_johnson_cook = false;
                        failure_max_pairwise_strain = false;
                        integration_point_wise = false;
                        failure_energy_release_rate = false;
                        //printf("constructed failure type\n");
                }
        };
        failure_types *failureModel;

        int ifix_tlsph;
        int update_method;

        class FixSMD_TLSPH_ReferenceConfiguration *fix_tlsph_reference_configuration;

private:
        double **Lookup; // holds per-type material parameters for the quantities defined in enum statement above.
        bool first; // if first is true, do not perform any computations, beacuse reference configuration is not ready yet.
};

}

#endif
#endif

/*
 * materialCoeffs array for EOS parameters:
 * 1: rho0
 *
 *
 * materialCoeffs array for strength parameters:
 *
 * Common
 * 10: maximum strain threshold for damage model
 * 11: maximum stress threshold for damage model
 *
 * Linear Plasticity model:
 * 12: plastic yield stress
 *
 *
 * Blei: rho = 11.34e-6, c0=2000, s=1.46, Gamma=2.77
 * Stahl 1403: rho = 7.86e-3, c=4569, s=1.49, Gamma=2.17
 */