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Extract data function with Matlab?

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Hello everyone,

I have a problem under Comsol with Matlab and i am sure it should be quiet easy to solve.

My model:

it´s a simple box (square with a=20km) with a very thin crack in the middle define as an ellipse (a=1m and b=1000m). I used a granite rheology (elastic material) for the box and the crack is full of .. void( doing the Boolean operation dif between the two geometry by substracting the ellipse from the box ).
What i am doing with this model is to apply an isotropic overpressure inside the crack to see how it deform.
My crack in the model is divide in 4 boundaries called 6,7,8 and 9 (1,2,3,4 are the boundaries of the box. The upper boundary of the crack are 6 and 8.

My Problem:

So now what i want to do under matlab is to extract the vertical displacement, generated by the overpressure, along the upper-part of my ellipse(along boundary 6 and 8) for a given x-coordinates ( that i can choose). The table should be: displacement in Y component in function of a chosen x coordinate along my crack (top boundaries). The reason i want to do that is to compare my displacement with some measured data.

I think i should use mphinterp to find the vertical displacement in function of a given x-coordinate but apparently it´s not working cause i think it needs the x and y coordinates.

Do you have an idea of how can i solve this problem ?is mphinterp relevant in my case or should i use something else?

PS: i am totally able to plot (under Matlab and Comsol) the vertical displacement in function of x-coordinate (along my top boundaries of the crack) but i dont know how to extract those data from a chosen x-coordinates

Please tell me if i am not clear enough

Best regards

Rémi

1 Reply Last Post 21 mars 2014, 13:33 UTC−4

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Posted: 1 decade ago 21 mars 2014, 13:33 UTC−4
Rémi,

can you obtain that value using Comsol's GUI?

In that way, you can then export it as an M-file and look for the appropriate command using Matlab.

Maybe, you can also define a point in your geometry that is irrelevant for the physics inside your model. Then, using mphinterp, evaluate inside that point.

hope it helps,
Felipe BM
Rémi, can you obtain that value using Comsol's GUI? In that way, you can then export it as an M-file and look for the appropriate command using Matlab. Maybe, you can also define a point in your geometry that is irrelevant for the physics inside your model. Then, using mphinterp, evaluate inside that point. hope it helps, Felipe BM

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