Plot variables

[raback]

Hi

I dont really know how this would be made totally generic. You can save the results as a table only if there is one variable. If the function has multiple variables then what should one do?

-Peter

[mzenker]

Hi,

functions of several variables would be the next step.

What I mean is if I have a material section like

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Material 1
  My Parameter = Real 0.5
  Thermal Conductivity = Variable Temperature; Real Procedure "Myconductivity.dll" "myconductivity"
  (...)
End

and in myconductivity.f90, I have something like

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FUNCTION myconductivity( Model, n, Temp ) RESULT(s)
(...)
TYPE(ValueList_t), POINTER :: VList
VList => GetMaterial(CurrentModel % CurrentElement)
myParameter = GetConstReal( VList, 'My Parameter')
s = Temp * myParameter ** 2
END FUNCTION myconductivity

I get a segmentation fault at the GetMaterial call. I suspect that this is because CurrentElement is undefined for a ListGetFun call of myconductivity. So I somehow need to supply a valid CurrentElement where I can set the temperature to the value(s) I would like to test.
I have begun to think about something like taking a node number, save its current state and then sweep the material assignment to this node through all available materials (or in fact, through all available bodies since as far as I understand the material assigment is derived from the body ID). Before tha actual simulation starts, I would restore the previously saved state.
Does that sound reasonable, or is there a more elegant way?

Matthias

[julien givernaud]

Hi,

On the same topic, it is possible to cheik a variable dependancy? For example electrical conductivity function of temperature ?
I try in ResultOutputSolver, the simple:
Variable i = Electric Conductivity
but in the log -> WARNING:: WriteVtuXMLFile: Nonexistent variable: electric conductivity

What is the trick to plot material properties in vtu format?

Regards

Julien

[mzenker]

Hi,

you have to use SaveMaterials/SaveScalars to do that. I think I did a similar thing some time ago, but don't have the time right now to look up the details. There are threads in this forum dealing with the subject, and the Models manual contains some info also.

HTH,

Matthias

[julien givernaud]

Thank you Matthias

I found in documentation informations about SaveMaterials solver.

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Solver i
Procedure = File "SaveData" "SaveMaterials"
Exec Solver = after simulation
Parameter 1 = Electric Conductivity
End

log file give:
SaveMaterials: Creating selected material parameters as fields
SaveMaterials: Parameter > electric conductivity < defined with 2403 dofs

Now how to make a plot of this parameters field in ResultOutputSolver...?
Try different things but no results

Julien

[mzenker]

Hi,

check out the SaveDependence solver which is in SaveData.src (see Peter's post earlier in this thread), it might already do what you need. You can call it right away since it is in the distribution already.
I went on and improved it in the meantime, but it is not yet ready to share. I am very busy with a totally different project right now and cannot go into details for at least the next one or two weeks, sorry.

HTH,

Matthias

[julien givernaud]

Hi,

It is possible to plot material properties after simulation in using Exported variable using body force section and exported variable, like this:

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Body 1
  Target Bodies(1) = 1
  Name = "Body 1"
  Equation = 1
  Material = 1
  Body Force = 1
  Initial condition = 1
End

Body Force 1
condTherm = Variable Temperature
Real MATC "tx(0)"
End
....
Solver 1
  Equation = Heat Equation
  Procedure = "HeatSolve" "HeatSolver"
  Calculate Loads = True
  Variable = Temperature
  Exec Solver = Always
  Stabilize = True
  Bubbles = False
  Lumped Mass Matrix = False
  Optimize Bandwidth = True
  Exported Variable 1 = condTherm
  !Nonlinear Update Exported Variables = Logical True
  Update Exported Variables = Logical True
....
End

...

You can plot for example thermal dependent properties and what you want.

Julien

[d.kojda]

Hi everyone,

Although this topic may be a bit older, I hope you don't mind me revisiting it. Like many before me, I would like to verify my User-Defined Function (UDF) before utilizing it in elmer within a particular temperature range.

To achieve this, I compiled a Fortran program that incorporates the UDF. During the compilation process, it is important to handle the type definitions correctly, which can be achieved by having the "defutils.mod" file present in the same directory as the program. For a win installation this file is found in "C:\Program Files\Elmer 9.0-Release\share\elmersolver\include".

The codes and compilation instructions:

The UDF definition file "own-materials.f90":

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!-----------------------------------------------------
! material property user defined function for ELMER:
! electrical conductivity as a function of temperature
! Written By: Anil Kunwar (2015-03-13)
! Modified by D.Kojda (2023-06-28)
!-----------------------------------------------------

FUNCTION getThermalConductivity_steel304( model, n, temp ) RESULT(condt)
! using "https://trc.nist.gov/cryogenics/materials/304Stainless/304Stainless_rev.htm"
! unit in W/(m*K)

! modules needed
USE DefUtils
IMPLICIT None
 
! variables in function header
TYPE(Model_t) :: model
INTEGER :: n
REAL :: temp, condt

! variables in function
REAL :: logTerm

! very important declaration, uncomment for debug printing in ElmerGUI
! CHARACTER(LEN=30) :: FMT

! Calculate the logarithmic term
logTerm = log(temp)/log(10.0)

!Calculate the NIST Polynom
condt = 10**(-1.4087 + 1.3982 * logTerm    + 0.2543 * logTerm**2 &
                     - 0.6260 * logTerm**3 + 0.2334 * logTerm**4 &
                     + 0.4256 * logTerm**5 - 0.4658 * logTerm**6 &
                     + 0.1650 * logTerm**7 - 0.0199 * logTerm**8)

!For Debug in ElmerGUI
!write(*,FMT="(A, 1pE11.3E3)") " Temperature = ", tx
!write(*,FMT="(A, 1pE11.3E3)") " Logterm = ", logTerm 
!write(*,FMT="(A, 1pE11.3E3)") " Thermal Conductivity = ", condt

END FUNCTION getThermalConductivity_steel304

The Fortran program "TestProperty.f90":

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PROGRAM TestProperty 
  USE DefUtils
  IMPLICIT NONE

  INTEGER :: i, numPoints
  REAL :: temp, conductivity
  REAL :: minTemp, maxTemp
  REAL :: getThermalConductivity_steel304

  TYPE(Model_t) :: model
  INTEGER :: n

  ! Define the number of points
  numPoints = 1000
  minTemp = 4.2 
  maxTemp = 300
  
  DO i = 1, numPoints
    temp = minTemp + (maxTemp - minTemp) / REAL(numPoints - 1) * REAL(i - 1)
    conductivity = getThermalConductivity_steel304(model, n, temp)
    WRITE(*,*) temp, conductivity
  END DO
  
END PROGRAM TestProperty

Compilation as shared dll object for use in elmer as usual (cmd in the path of the *.f90 files):

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elmerf90 -o own-materials.dll own-materials.f90

Compilation of the testprogram using the elmer-provided fortran compiler (cmd in the path of the *.f90 files):

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"C:\Program Files\Elmer 9.0-Release\stripped_gfortran\bin\x86_64-w64-mingw32-gfortran.exe" -o TestProperty.exe TestProperty.f90 own-materials.f90

Run the test program (cmd in the path of the compiled *.exe file):

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TestProperty.exe 

Program output (values here are as expected):

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   4.19999981      0.290716350
   4.49609566      0.318263769
   4.79219198      0.346298039
  ...
   299.407806       15.2935171
   299.703918       15.3009739
   300.000000       15.3089056

It may be worth noting, that I had compiling issues with following common lines in the "own-materials.f90", as the compiler does not know where GetMaterial() and Fatal() are defined. Hence, these lines were removed in "own-materials.f90".

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! get pointer on list for material
material => GetMaterial()
IF (.NOT. ASSOCIATED(material)) THEN
  CALL Fatal('getConductivity', 'No material found')
END IF

I also tried to use the *.dll file from python, but I think there are issues with the iso_c_bindings using the elmerf90 compiler.

I hope this information proves helpful to someone in the future.

Danny