Menu

Discussion Forum

New Discussion
查找

Note: This discussion is about an older version of the COMSOL Multiphysics® software. The information provided may be out of date.

Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

Ivar Kjelberg please help! About the shape of PML in comsol 4.4

Posted 2014年6月24日 GMT-4 03:56 RF & Microwave Engineering, Wave Optics, Geometry, Modeling Tools & Definitions, Parameters, Variables, & Functions Version 4.4 6 Replies

Meng
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Dear Ivar Kjelberg,
I have a question in my simulation. I use the RF module, I was calculating the effective index of the photonic crystal fiber. The shape of the cross section is a hexagonal, the outside is a circle. I want to set the region between the hexagonal and the circle as a PML, and I chose the cylindrical coordinate. But every time comsol said:"Could not find any spherical or cylindrical regions". When I set Cartesian coordinate, the error appear again.

So my question is: does it mean that the pml must be a standard rectangle, circle or concentric? (But in comsol v4.2. the pml region can be arbitrary, it don't have this problem.)

I will appreciate it very much for your helps!
6 Replies Last Post 2014年12月19日 GMT-5 21:24
COMSOL Moderator

Hello Meng

Your Discussion has gone 30 days without a reply. If you still need help with COMSOL and have an on-subscription license, please visit our Support Center for help.

If you do not hold an on-subscription license, you may find an answer in another Discussion or in the Knowledge Base.

Zhagsalag Akhyn
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 10 years ago 2014年10月8日 GMT-4 05:03
I have the same problem. Does anybody know how to solve it?
I have the same problem. Does anybody know how to solve it?
Meng
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 10 years ago 2014年10月13日 GMT-4 05:48
I solved it myself, do not set an arbitrary shape of PML, just use circular or rectangular. By careful mesh, the results will be good!
I solved it myself, do not set an arbitrary shape of PML, just use circular or rectangular. By careful mesh, the results will be good!
Zhagsalag Akhyn
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 10 years ago 2014年10月14日 GMT-4 11:48

I solved it myself, do not set an arbitrary shape of PML, just use circular or rectangular. By careful mesh, the results will be good!

Have you solved for 3D spherical or rectangular PML? when i tried i get some other kind of error.
[QUOTE] I solved it myself, do not set an arbitrary shape of PML, just use circular or rectangular. By careful mesh, the results will be good! [/QUOTE] Have you solved for 3D spherical or rectangular PML? when i tried i get some other kind of error.
Meng
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 10 years ago 2014年10月21日 GMT-4 02:27
3D spherical maybe easier, you can refer to the example model of comsol(for example, dipole antenna ), do not forget to use swept mesh!
I hope this help.
3D spherical maybe easier, you can refer to the example model of comsol(for example, dipole antenna ), do not forget to use swept mesh! I hope this help.
Zeba Naqvi
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 10 years ago 2014年12月19日 GMT-5 16:50
Hello,
I am new to Comsol. I tried to make a simple 2D axisymmetric model with a core circular region 5um in radius of refractive index 1.7 and 0.5 um thick outer circular region of refractive index 1.6. Then added PML at radius 20um and meshed. I selected geometry cylindrical. When I compute, the error is "could not fund any cartesian regions - Feature : perfectly matched layer"
What should I do? Thanks
Hello, I am new to Comsol. I tried to make a simple 2D axisymmetric model with a core circular region 5um in radius of refractive index 1.7 and 0.5 um thick outer circular region of refractive index 1.6. Then added PML at radius 20um and meshed. I selected geometry cylindrical. When I compute, the error is "could not fund any cartesian regions - Feature : perfectly matched layer" What should I do? Thanks
Meng
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 10 years ago 2014年12月19日 GMT-5 21:24
When the geometry is set to be cylindrical, the problem should have been solved. Moreover, your PML is too thick, one or two lmd is ok!
When the geometry is set to be cylindrical, the problem should have been solved. Moreover, your PML is too thick, one or two lmd is ok!

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.

Suggested Content