Menu

Discussion Forum

New Discussion
Filter

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 The information provided may be out of date.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.

Help: PML Scaling Factor and Implemantation In RF Module

Posted Aug 15, 2014, 4:18 p.m. EDT RF & Microwave Engineering Version 4.4 1 Reply

Mohammad Parvinnezhad Hokmabadi
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Dear All,

Can somebody tell me what is PML scaling factor and curvature parameter in PML of RF 4.4?
I am going to sweep a large frequency range 4.8e14-8.8e14 in my simulation.
The structure is easy. Air and Substrate. both are semi-infinite.
I wanna use PML surrounding the structure and finally calculate reflection.
I attached the file.
I appreciate if you reply.
I discussed this problem with more detail also in
www.comsol.com/community/forums/general/thread/46787/
Please help.

Thanks,
Mohammad

Attachments:

1 Reply Last Post Jan 10, 2016, 9:26 p.m. EST
COMSOL Moderator

Hello Mohammad Parvinnezhad Hokmabadi

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.

Shreyank Gupta
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 9 years ago Jan 10, 2016, 9:26 p.m. EST
Hello Mohammad Parvinnezhad Hokmabadi,

I did the simulation for PML behavior changing scaling and curvature parameter factor. I did this thing for acoustic in frequency domain. There are some points which I noticed to best describe PML:

1. PML material should be same as it's neighboring boundary and it's width should be typical greater than 5 wavelengths.
2. curvature parameter factor should never be negative
3. Scaling or absorption factor should be greater than 2/or smaller than -2 while curvature parameter factor should be greater than 3. If you keep both to 1 you will have reflections. Though I don't know the reason why curvature factor should be always positive. May be if you know you can tell me this thing.

Thanks and regards,
Shreyank Gupta
Hello Mohammad Parvinnezhad Hokmabadi, I did the simulation for PML behavior changing scaling and curvature parameter factor. I did this thing for acoustic in frequency domain. There are some points which I noticed to best describe PML: 1. PML material should be same as it's neighboring boundary and it's width should be typical greater than 5 wavelengths. 2. curvature parameter factor should never be negative 3. Scaling or absorption factor should be greater than 2/or smaller than -2 while curvature parameter factor should be greater than 3. If you keep both to 1 you will have reflections. Though I don't know the reason why curvature factor should be always positive. May be if you know you can tell me this thing. Thanks and regards, Shreyank Gupta

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