Same newbee, next step

[Don]

Thanks to everyone who helped m over the last few days. My thermal simulations are working great now

The next step is to change the boundary condition temperature over time for the simulation.

My project is kind of a forensic analysis to determine what happened to a shipment of liquid material that was left in a truck over a weekend during the hottest part of summer. The material has an upper temperature limit for storage, and we “know” the material was damaged, but would like to visually demonstrate what happened.

I have hourly temperature records for the 60 hour period in question.

I would like to use these temperatures as the boundary condition during my simulation.

What is the right way to set this up using the ElmerGUI ?

Another thing that would help a great deal is to show the simulation elapsed time in the frame (or at least the frame number) during post processing, is there any way to do this?

Thanks again
Don

[petroo]

Hi Don,

Thanks to everyone who helped m over the last few days. My thermal simulations are working great now

Great! Congratulations!

I have hourly temperature records for the 60 hour period in question.

I would like to use these temperatures as the boundary condition during my simulation.

I wouldn't do this via ElmerGUI but by hand-editing the SIF file. It happens that I just had a fun problem that I wanted to take a look at ("How long do you have to boil sausages in the soup in order to get them sufficiently hot?"). I simulated the temperature rise of the soup by setting the boundary conditions of the sausage hull accordingly, and after reaching 100 °C kept the soup boiling at that temperature.

The respective code part in the SIF file for me:

Code: Select all

Boundary Condition 1
  Target Boundaries(1) = 1
  Name = "sausage hull"
  Temperature = Variable Time
    Real
    0          20
    600	100
    1000    100
End

This means that I start out with a temperature of 20 °C, need 600 sec to reach the 100 °C in a linear fashion, and then silently boil the soup further at that temperature until reaching 1000 sec.

I guess you would need about the same functionality. Alternatively you can put MATC statements into the same place.

Regards,

Peter

[Don]

I wouldn't do this via ElmerGUI but by hand-editing the SIF file. It happens that I just had a fun problem that I wanted to take a look at ("How long do you have to boil sausages in the soup in order to get them sufficiently hot?"). I simulated the temperature rise of the soup by setting the boundary conditions of the sausage hull accordingly, and after reaching 100 °C kept the soup boiling at that temperature.

Thanks Peter, that looks like it will do exactly what I need.

Regards
Don

[mzenker]

This can be done also in ElmerGUI:
Model-> Boundary Condition -> Add-> Heat Equation.
When you place the cursor in the "Temperature" field and hit the Return key, a window opens where you can enter

Variable Time
Real
0 20
600 100
1000 100
End

The effect on the sif file should be the same as when you edit it by hand, but you can still continue to use ElmerGUI.

HTH,

Matthias