Menu

Discussion Forum

New Discussion
Filtra

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 The information provided may be out of date.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.

How accurate is Comsol compared to FDTD

Posted 25 giu 2014, 10:33 GMT-4 RF & Microwave Engineering, Geometry, Mesh, Modeling Tools & Definitions, Parameters, Variables, & Functions, Studies & Solvers Version 3.5a 1 Reply

Naema Othman
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Hi:
I am a comsol user. My supervisor asked me to re simulate a design that was done in FDTD using Comsol.
The problem I got is that my solution was not the same as the FDTD solution!!. I am sure I have no error but I have to check with you (comsol community) in case someone can help me figure out what is going on.
I solved for RF (MODE ANALYSIS) and the effective index I got was 3.81. However, the FDTD solution was 3.88.
The shape of the mode I got with Comsol is clearly different from the one done with FDTD.

Any help?. Should I give you the two files to see them?
1 Reply Last Post 25 giu 2014, 11:13 GMT-4
Pu Zhang
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 25 giu 2014, 11:13 GMT-4
According to my very limited experience with COMSOL's mode solver, good accuracy requires very fine mesh. So probably you can try to do some convergence study with mesh size.

As for mode profile, if you have degenerate modes, the pattern has certain arbitrariness. Linear combinations of them are also eigenmodes. You could check this.
According to my very limited experience with COMSOL's mode solver, good accuracy requires very fine mesh. So probably you can try to do some convergence study with mesh size. As for mode profile, if you have degenerate modes, the pattern has certain arbitrariness. Linear combinations of them are also eigenmodes. You could check this.

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