Line data    Source code

       1              : // Copyright 2024, UChicago Argonne, LLC
       2              : // All Rights Reserved
       3              : // Software Name: NEML2 -- the New Engineering material Model Library, version 2
       4              : // By: Argonne National Laboratory
       5              : // OPEN SOURCE LICENSE (MIT)
       6              : //
       7              : // Permission is hereby granted, free of charge, to any person obtaining a copy
       8              : // of this software and associated documentation files (the "Software"), to deal
       9              : // in the Software without restriction, including without limitation the rights
      10              : // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
      11              : // copies of the Software, and to permit persons to whom the Software is
      12              : // furnished to do so, subject to the following conditions:
      13              : //
      14              : // The above copyright notice and this permission notice shall be included in
      15              : // all copies or substantial portions of the Software.
      16              : //
      17              : // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
      18              : // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
      19              : // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
      20              : // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
      21              : // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
      22              : // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
      23              : // THE SOFTWARE.
      24              : 
      25              : #include "neml2/models/solid_mechanics/AssociativePlasticFlow.h"
      26              : #include "neml2/tensors/Scalar.h"
      27              : #include "neml2/tensors/SR2.h"
      28              : #include "neml2/tensors/SSR4.h"
      29              : 
      30              : namespace neml2
      31              : {
      32              : register_NEML2_object(AssociativePlasticFlow);
      33              : 
      34              : OptionSet
      35            2 : AssociativePlasticFlow::expected_options()
      36              : {
      37            2 :   OptionSet options = FlowRule::expected_options();
      38            2 :   options.doc() +=
      39              :       " This object calculates the rate of plastic strain following associative flow rule, i.e. "
      40              :       "\\f$ \\dot{\\boldsymbol{\\varepsilon}}_p = - \\dot{\\gamma} \\frac{\\partial f}{\\partial "
      41              :       "\\boldsymbol{M}} \\f$, where \\f$ \\dot{\\boldsymbol{\\varepsilon}}_p \\f$ is the plastic "
      42              :       "strain, \\f$ \\dot{\\gamma} \\f$ is the flow rate, \\f$ f \\f$ is the yield function, and "
      43            2 :       "\\f$ \\boldsymbol{M} \\f$ is the Mandel stress.";
      44              : 
      45            6 :   options.set_input("flow_direction") = VariableName(STATE, "internal", "NM");
      46            2 :   options.set("flow_direction").doc() = "Flow direction which can be calculated using Normality";
      47              : 
      48            6 :   options.set_output("plastic_strain_rate") = VariableName(STATE, "internal", "Ep_rate");
      49            2 :   options.set("plastic_strain_rate").doc() = "Rate of plastic strain";
      50              : 
      51            2 :   return options;
      52            0 : }
      53              : 
      54            4 : AssociativePlasticFlow::AssociativePlasticFlow(const OptionSet & options)
      55              :   : FlowRule(options),
      56            4 :     _NM(declare_input_variable<SR2>("flow_direction")),
      57            8 :     _Ep_dot(declare_output_variable<SR2>("plastic_strain_rate"))
      58              : {
      59            4 : }
      60              : 
      61              : void
      62            8 : AssociativePlasticFlow::set_value(bool out, bool dout_din, bool /*d2out_din2*/)
      63              : {
      64              :   // For associative flow,
      65              :   // Ep_dot = gamma_dot * NM
      66              :   //     NM = df/dM
      67              : 
      68            8 :   if (out)
      69            7 :     _Ep_dot = _gamma_dot * _NM;
      70              : 
      71            8 :   if (dout_din)
      72              :   {
      73            4 :     auto I = SR2::identity_map(_gamma_dot.options());
      74              : 
      75            4 :     if (_gamma_dot.is_dependent())
      76            4 :       _Ep_dot.d(_gamma_dot) = _NM;
      77              : 
      78            4 :     if (_NM.is_dependent())
      79            4 :       _Ep_dot.d(_NM) = _gamma_dot * I;
      80            4 :   }
      81            8 : }
      82              : } // namespace neml2