Generalized Plane Strain in the new Lagrangian Kernel System

[pbandil]

Hello Developers,

I have written a custom material (inherited from computeQpPK2Stress, similar to ComputeNeoHookeanStress). I am using the new Lagrangian kernel system within the solid mechanics module. I now want to use generalized plane strain for my problem, and when I use the feature planar_formulation within the Quasistatic block, it throws an error stating that generalized plane strain is not supported when new_system = true.

[Physics]
  [SolidMechanics]
    [QuasiStatic]
      [all]
        add_variables = true
        displacements = 'ux uy'
        strain      = FINITE
        new_system  = true
        formulation = TOTAL  
        planar_formulation = GENERALIZED_PLANE_STRAIN # this throws an error
        generate_output = 'cauchy_stress_xx cauchy_stress_yy cauchy_stress_zz cauchy_stress_xy cauchy_stress_xz cauchy_stress_yz' 
      []
    []
  []
[]

It says that I need to do that manually. I modified my Physics block to the following:

[Physics]
 [SolidMechanics]
   [QuasiStatic]
     [all]
       add_variables = true
       displacements = 'ux uy'
       strain      = FINITE
       new_system  = true
       formulation = TOTAL   
       generate_output = 'cauchy_stress_xx cauchy_stress_yy cauchy_stress_zz cauchy_stress_xy cauchy_stress_xz cauchy_stress_yz' 
     []
   []
   [GeneralizedPlaneStrain]
     [gps]
       displacements = 'ux uy'
       scalar_out_of_plane_strain = scalar_strain_zz
       # out_of_plane_pressure = traction_function
     []
   []
 []
[]

It then gives the following errors:

The following occurred in the Problem 'MOOSE Problem' of type FEProblem.

Material property 'Jacobian_mult', requested by 'gpsGeneralizedPlaneStrainOffDiag_disp0' is not defined on block 0
Material property 'Jacobian_mult', requested by 'gpsGeneralizedPlaneStrainOffDiag_disp1' is not defined on block 0
Material property 'Jacobian_mult', requested by 'gps_GeneralizedPlaneStrainUserObject' is not defined on block 0
Material property 'stress', requested by 'gps_GeneralizedPlaneStrainUserObject' is not defined on block 0
#######################################################################################

I assume I need to make some changes to my custom material code, but I don't know what needs to be done precisely to run the generalized plane strain model. Please help. Thanks.

[GiudGiud]

Hello

I think by manually it means to not use the Physics at all.
I think you should use the DumpObjectsProblem to output the list of objects created by:

• non-lagrangian kernels + generalized plane strain
• lagrangian kernels
  https://mooseframework.inl.gov/source/problems/DumpObjectsProblem.html

and work from the second one to include the generalized plane strain manually.
This may involve additional development.
@hchen139 @gambka @reverendbedford is this sound advice? Or do you see a path forward with the Physics?