Tutorial 1: Basic diffusion is zero

[mhelel]

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Issue or question about MOOSE

I tried to recreate "Tutorial 1: Application Developement". I basically copied the code, it ran, converged but when I visualized it with python and Paraview (Peacock is not working for me) the pressure was zero everwhere. This can't be right. I triplechecked everything, changed it to 1D etc but it still is 0. Has Anyone an idea or encountered a similar thing?

Maybe it is just a visualization problem. I sent my input and output file in the zip.

Tutorial1.zip

(Optional) code in question / simulation log / errors

(moose) problems $ ../babbler-opt -i pressure_diffusion.i
Framework Information:
MOOSE Version:           git commit 7263c936d4 on 2025-08-19
LibMesh Version:         a9f56e9ed51a235edbcfecb00522389977663817
PETSc Version:           3.23.4
SLEPc Version:           3.23.2
Current Time:            Tue Aug 26 14:40:59 2025
Executable Timestamp:    Tue Aug 26 06:31:51 2025

Input File(s):
  /home/s-mihelb/BachelorThesis/projects/babbler/problems/pressure_diffusion.i

Checkpoint:
  Wall Time Interval:      Every 3600 s
  User Checkpoint:         Disabled
  # Checkpoints Kept:      2
  Execute On:              TIMESTEP_END 

Parallelism:
  Num Processors:          1
  Num Threads:             1

Mesh: 
  Parallel Type:           replicated
  Mesh Dimension:          2
  Spatial Dimension:       2
  Nodes:                   1111
  Elems:                   1000
  Num Subdomains:          1

Nonlinear System:
  Num DOFs:                1111
  Num Local DOFs:          1111
  Variables:               "pressure" 
  Finite Element Types:    "LAGRANGE" 
  Approximation Orders:    "FIRST" 

Execution Information:
  Executioner:             Steady
  Solver Mode:             NEWTON 
  PETSc Preconditioner:    hypre boomeramg 
  MOOSE Preconditioner:    SMP (auto) 
 0 Nonlinear |R| = 9.589189e+02
      0 Linear |R| = 9.589189e+02
      1 Linear |R| = 4.437909e+01
      2 Linear |R| = 1.208598e+00
      3 Linear |R| = 4.488848e-02
      4 Linear |R| = 3.043818e-03
 1 Nonlinear |R| = 3.043818e-03
      0 Linear |R| = 3.043818e-03
      1 Linear |R| = 2.152425e-04
      2 Linear |R| = 1.775675e-05
      3 Linear |R| = 8.116262e-07
      4 Linear |R| = 6.354141e-08
      5 Linear |R| = 3.106664e-09
 2 Nonlinear |R| = 3.106584e-09
 Solve Converged!

Encountering Errors? Please include diagnostic output

No response

[GiudGiud]

Hello

Paraview defaults to showing you the initial condition. You will want to click to reach the next non-zero solution

This is a setting you can change in Preferences btw. It saves a ton of time

[mhelel]

Thanks a lot. This helped. I didn't even realize it saves the initial condition. Especially since I only found one Array of data when examining it in python.