How to change the boundary condition based on timestep in transient thermal analysis

[TakumiN]

Hi community!
I want to make a model that for the first 600 seconds the surface is heated with heat flux 10000W/m^2, then after that for another 600 seconds it stops heating the surface and releases heat to the external air(external temperature = 288K).

I would appreciate it if you would teach me how to write this down in the sif file.

Below is one part of the model that only heats the surface for 600 seconds.
Thanks for your kindness.

Code: Select all

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Simulation
  Max Output Level = 1
  Coordinate System = Cartesian
  Coordinate Mapping(3) = 1 2 3
  Simulation Type = Transient
  Steady State Max Iterations = 20
  Output Intervals = 2
  Timestep intervals = 600
  Timestep Sizes = 1
  Timestepping Method = BDF
  BDF Order = 2
  Solver Input File = case.sif
  Post File = case.vtu
End

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Boundary Condition 1
  Target Boundaries(1) = 1
  Name = "Air-Facing Interface"
  Heat Flux = 10000
End

[kevinarden]

You can use a table or a MATC function

Heat Flux = Variable Time
Real
0 10000
600 10000
601 0
1200 0
End

Heat Flux = Variable Time; Real MATC "(if tx(0)<600);10000;else 0"

[TakumiN]

Thank you Kevin!

Heat Flux = Variable Time
Real
0 10000
600 10000
601 0
1200 0
End

This one worked very well.
You made my day, I appreciate you again for your big big kindness!