Loading in RZ 2-D case

[sidharthsarmah]

Hi @GiudGiud , I want to do perform a tensile test of a specimen as shown.

1. I want to apply a load on the end face, how do I apply a point load on the face, but it is basically an average the entire area.
2. Is it enough in MOOSE the just change the coordinate to RZ type for changing the 3D to 2D as shown? How does MOOSE know which is the R or Z direction?

[Problem]
  type = FEProblem
  coord_type = RZ
[]

[GiudGiud]

Hello

1. You ll want to apply the load on a sideset then. Depending on the object you use, you will likely specify the local value of the tension, so the average

2. The coord_type is actually in the Mesh block now.
   It should be enough to provide a 2D mesh.
   Note that you do not need the entire mesh, half is enough because of the symmetry

Guillaume

[GiudGiud]

this looks fine to me, if it gets parsed. I usually write ParsedFunctions but I think these expressions in the input will be parsed

[GiudGiud]

though in the post you say

Similarly till t=10s, the force, F1=0 and once t>10s, F1=0.01*t, is these syntax correct?

but in the input it's t*0.001 not 0.01

[sidharthsarmah]

Hi @GiudGiud , is this correct?

[NodalKernels]
  [./force_z]
    type = UserForcingFunctionNodalKernel
    variable = disp_x
    boundary = 'right'
    function = 'force'
  [../]
[]

  [./s_conc]
    type = ADFunctionDirichletBC
    variable = cL
    boundary = 'Hsurface'
    function = 'conc'
  [../]

[Materials]
  [./force_cond]
    type = ADParsedMaterial
    expression = 'if(t<10, 0, t*0.001)'
    property_name = 'force'
  [../]

  [./conc_cond]
    type = ADParsedMaterial
    expression = 'if(t<10, 0.127, 0)'
    property_name = 'conc'
  [../]

[GiudGiud]

this looks good to me

[sidharthsarmah]

Hi @GiudGiud @bwspenc , I am having problem pin applying a displacement BC to the end face. The examples in MOOSE has boundary defined as front back etc, because of which I am a bit confuse on whether I should apply to a point or entire point or how do I apply to the top cylinder.

The way it is done in ABAQUS is define a reference point for the entire top portion something like this, how do I impose the same BC in MOOSE for a 2D case:

[GiudGiud]

Hello

Where it applies is really defined by the sideset / node sets in use.

So maybe send me your mesh to check where it s being applied?

Guillaume

[GiudGiud]

I dont think we have that concept in moose
Prescribing the displacement on all nodes in a BC is one way to perform the tensile test. Another is to prescribe a force / stress

[sidharthsarmah]

Thanks @GiudGiud , as you suggested to use Parsedmaterial instead, I used it but I am getting this error:

*** ERROR ***
Invalid function
if(t> 86400, 0, t*3e-3)

in ParsedMaterialHelper.
Syntax error: Unknown identifier

[BC]
  [./x_load]
    type = ADFunctionDirichletBC
    variable = disp_x
    boundary = 'Load_x'
    function = 'force'
  [../]
[]
[Materials]
  [./force_cond]
    type = ADParsedMaterial
    expression = 'if(t> 86400, 0, t*3e-3)'
    property_name = 'force'
  [../]
[]

[GiudGiud]

hello

it's a FunctionDirichletBC so you have to use a Function not a Material
So a ParsedFunction instead of a ParsedMaterial

Guillaume

[sidharthsarmah]

Hi @GiudGiud error:

*** ERROR ***
Task add_material is not registered to build Function derived objects

  [./conc_cond]
    type = ADParsedFunction
    expression = 'if(t<86400, 12371.43, 0)'
    property_name = 'conc'
  [../]

[GiudGiud]

I think Functions go in the Functions block not the Materials block