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Hi

could it be linked to the reply from here ?

www.comsol.eu/community/forums/general/thread/15851/#p43553

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Good luck
Ivar

Hi Ivar

I did what was said but did not answered :(

all problems are in 2D but my problem is in 3D does it makes changes? for example one which is odd is

in ALE I can define just free deformation, when I define prescribed mesh velocity or mesh displacement there is no object selectable and all surfaces became not applicable!!

could you say where is my problem please,
could you take a look at the file pleasee.

Navid

Ivar

could you please take a look at the file in previous message and see what is my problem please :( I am stuck in this simple problem for a long long time :( and it makes me so confused. I just want to move a block over the other and get a rational temperature contour in the bottom block :( in 3D

I appreciate it,

Hi

now I do not have 4.0 so my 2D HT+ALE model attached a 4.1.0.185 is probably not useful for you.

What I did was to use ALE instead of deformed geometry (see the KB), with assembly mode and an identity continuity condition for the contact surface

Then there is an open discussion about the frame to use, I believe the spatial (default) one is the best, in my model the results are wrong if I select one of the others, but on another thread, there was something wrong in the case of a rotary heat exchange in the same physics, but it could be something else too, such models should ideally be remade from scratch time to time, to be sure that all tries and changes has not changed a setting a couple of levels down

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Good luck
Ivar

Hi Ivar

I am very thankful for your model. I tried to open your file in version 4.1 but it said "expected end of central directory record signature" ! is it kind of zipped or something. I think this would be really helpful fro me because I think I have problem with how to do the 'assembly mode and an identity continuity condition for the contact surface" because when you do the 3D simulation the contact surface is just one surface and i do not know how continuity works if it should be between two surfaces how it would work when we have just one surface between top and bottom blocks!

I appreciate your helps, I feel it is gonna to work by your help.

Thanks

Hi Ivar

I wanted to say I can not use HT in solids. in my problem I have a vertical cylindrical hole in the bottom block say in location x and is filled with another material something like discontinuity in bottom box. so if the heat wants to transfer in bottom box from right to left then it will not be same situation for the temperature contours after the hole.

and also in the contact surface in bottom block we should have the same temperature as upper box but as you see in figure, I have defined motion in x direction 0.0025 m/s and the length is 5 cm so when time is 20 sec all the top surface should be somehow red but it is still blue :(

and the main problem is th temperature distribution after the hole as you see is not simulating real contours as hot box moves.

please take a look at pic and file. thank you so much Ivar

Hi Ivar

I could open your file, that is definitely what I want thank you :), I am going over it to see how you did the simulation. actually my main problem was how to define the pairs. when I do the 3D simulation the contact surface counts as one common surface and it is not like on surface from the top block and one from the bottom to have a common surface.

anyhow thank you sooo much :)

I am going over it please let me know if you have any comment on how to have COMSOL to not combine surfaces and let me to select the surfaces separately.

Thanks again

I haven't read the whole thread, only your initial question. So this may have been already suggested:
If the deformation in question is strictly rigid body motion or rotation, easiest way to do what you want is to take advantage of convective terms in the heat equation. For example, you can simulate the effect of body translation by simply assigning it a velocity in the translation direction. I haven't thought about how you would model the ends of the box domains though.
good luck
Ozgur

Hi

of you have only 1 boundary, it is because you are in "Finish Union mode" this implies unicity on all boundaries, you should use "Assembly Finsih mode inthe geoemtry, and for a simple case "without" imprints. Indeed my model is v4.1.0.185, so you must have that version to load it, I do no longer have the older version up running

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Good luck
Ivar

I would like to add a supplementary question to this thread. I don't have a picture of what I'm going to describe, but hopefully, it's clear enough...Extending from Navid's model, what if I wanted to have a protrusion from the top block into the bottom block and have it traverse through the material of the bottom block (such as if the bottom domain was a liquid and the top solid). After each time increment, the mesh would need to update to accommodate the new topology...or maybe not a new topology since the connectivity isn't necessarily changing (or is it?). 1) Is this possible strictly with the GUI (i.e. no Matlab Livelink or other programming required) and, if so, 2) How would I implement it in a similar fashion to what Ivar has done in this example?

Thank you.