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Rotated system in 2D simulation

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Hi,

I am interested in simulating the cross section (2D) of a piezoelectric device, with an arbitrary rotation of the material's crystal axes. The process is simple enough in 3D simulations, using Euler angles. In 2D, however, the "rotated system" behavior is slightly less clear. For clarity, I will refer to the "global" coordinates as those corresponding to how the model is viewed on my screen -- X is left to right, Y is up and down, and Z is into/out of the screen.

The desired outcome is to have the material X axis aligned with the global Y axis, and rotate the material Y and Z axes around the global XZ plane.

The "rotated system" option only allows a rotation "about the out-of-plane axis", which at first glance seems unable to do what I want (which would require rotating around the vertical axis/global Y). If I understand correctly, this is also independent of which axis I choose as "out-of-plane".

Is this actually a limitation of the 2D rotated system option in 5.3?

Thank you!


2 Replies Last Post Dec 31, 2020, 1:07 p.m. EST

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Posted: 4 years ago Dec 31, 2020, 10:36 a.m. EST

If the rotations you want to do are multiples of pi/2 then all you need to do is choose one of the six available options for the material coordinate system.

If not multiples of pi/2- say, 38 degree rotated lithium tantalate- then you can't solve the problem in 2D.

If the rotations you want to do are multiples of pi/2 then all you need to do is choose one of the six available options for the material coordinate system. If not multiples of pi/2- say, 38 degree rotated lithium tantalate- then you can't solve the problem in 2D.

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Posted: 4 years ago Dec 31, 2020, 1:07 p.m. EST

Dave,

Thanks for the response. I do indeed want angles which are not multiples of pi/2 (being able to sweep smoothly over a ~pi rotation would actually be best). It seems strange to have this restriction for 2D simulations... Some of the online documentation for 5.5 suggests that Euler angles are an option for 2D simulations, do you know if that is true?

Thanks.

Dave, Thanks for the response. I do indeed want angles which are not multiples of pi/2 (being able to sweep smoothly over a ~pi rotation would actually be best). It seems strange to have this restriction for 2D simulations... Some of the online documentation for 5.5 suggests that Euler angles are an option for 2D simulations, do you know if that is true? Thanks.

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