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Transmit time-dependent solution with Time Space dependent Interpolation function or directly

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Hello!
I want to use a velocity boundary solution u(x, t) from one physics in another physics. The timesteps, the mesh and the geometry are equal. I use the Laminar Two Phase Flow, level Set physics twice in COMSOL 4.3. I have red a lot of post, but I couldn't find a solution. Especially in 4.3. I followed two approaches:

1. I tried to use the dependent variable u from solution 1. With the solver notes I just can transmit one step from solution 1 to the initial conditions of solver 2. But I want the whole velocity over time used for computing. Have I done anything wrong? Is it possible to hand over the solution1 for every time step?

2. I exported the solution 1 on the boundary as a 1D Line Graph at all times as a spreadsheet. Then I changed the exported txt file to the standard COMSOL spreadsheet column1=x column2=t and column3=u(x, t) It looks like:
0 0 0.34
0.2 0 0.16
0.3 0 0.31
0 0.1 0.28
0.2 0.1 0.19
0.3 0.1 0.23
0 0.2 0.29 and so on.
Then I imported it in the definitions (I tried global and local) note as a interpolation function int1 (x, y). I defined the units. When I call the function in the physic via u(x, t) no errors occur. But in the results I can see that the function doesn't transmit time-dependent values. Maybe I've done an mistake? Does anyone know?

Which approach is the better one fpr COMSOL 4.3? Where could be the mistake?

Thanks for any help!


2 Replies Last Post 2 nov. 2012, 18:30 UTC−4

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Posted: 1 decade ago 2 nov. 2012, 12:10 UTC−4
I now introduced a counter in the spreadsheet as first column. The counter is depenendent on x and t. This was recommended in another thread.

Does anyone know to handle timedependent data transmission within one model and two physics?
I now introduced a counter in the spreadsheet as first column. The counter is depenendent on x and t. This was recommended in another thread. Does anyone know to handle timedependent data transmission within one model and two physics?

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Posted: 1 decade ago 2 nov. 2012, 18:30 UTC−4
I'm really helpless. Do you think I should loopthe velocity with Matlab? I don't know which idea to follow. I'm so confused right now. If nobody has an answer to my problems, is there anyone you has the same problem?
I'm really helpless. Do you think I should loopthe velocity with Matlab? I don't know which idea to follow. I'm so confused right now. If nobody has an answer to my problems, is there anyone you has the same problem?

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