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 The information provided may be out of date.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.

Rectangular input port phase shift possible bug (microwave heating)

Posted 5 apr 2013, 06:19 GMT-4 RF & Microwave Engineering Version 4.3a 2 Replies

Luca De Stefano
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Hi all,

I'm working with the microwave heating module to simulate the heating of a load with highly non-linear material properties (varying with temperature).

I have two input ports both set on ON.

Since using coaxial ports the model doesn't converge, I am using rectangular ports and it works (very slow but it works).

The problems start when i try to phase shift the 2 input ports; when I modify the phase of one port (the internal variable name is 'Thetap') and I compute, Comsol suddenly crashes and closes.

Is it a bug? Am I doing something wrong?

(if you want to try and see yourself you can draw a cavity with two rectangular ports and vary the phase on one of the two, it's very fast and simple)

Thanks!

Luca
2 Replies Last Post 5 apr 2013, 06:35 GMT-4
Edgar J. Kaiser Certified Consultant
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 5 apr 2013, 06:31 GMT-4

Hi,

I recently did some work that involved two uniform lumped ports with a phase shift in the RF module. This worked without problems.

There was one thing that surprised me though: The phase imput field didn't accept a parameter. It only worked with an explicit number. If I used a parameter it was treated as zero.

Cheers
Edgar

--
Edgar J. Kaiser
www.emphys.com
Hi, I recently did some work that involved two uniform lumped ports with a phase shift in the RF module. This worked without problems. There was one thing that surprised me though: The phase imput field didn't accept a parameter. It only worked with an explicit number. If I used a parameter it was treated as zero. Cheers Edgar -- Edgar J. Kaiser http://www.emphys.com
Luca De Stefano
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 5 apr 2013, 06:35 GMT-4

Hi,

I recently did some work that involved two uniform lumped ports with a phase shift in the RF module. This worked without problems.

There was one thing that surprised me though: The phase imput field didn't accept a parameter. It only worked with an explicit number. If I used a parameter it was treated as zero.

Cheers
Edgar

--
Edgar J. Kaiser
www.emphys.com


Thanks for the answer, for me it worked with coaxial ports, apparently the problem concerns only rectangular ports..

The problem is that with rect ports my simulation finds a solution, with coaxial ports it doesn't.. maybe i could try lumped ports, but i think it would go too far from my real model..

Thanks

Luca
[QUOTE] Hi, I recently did some work that involved two uniform lumped ports with a phase shift in the RF module. This worked without problems. There was one thing that surprised me though: The phase imput field didn't accept a parameter. It only worked with an explicit number. If I used a parameter it was treated as zero. Cheers Edgar -- Edgar J. Kaiser http://www.emphys.com [/QUOTE] Thanks for the answer, for me it worked with coaxial ports, apparently the problem concerns only rectangular ports.. The problem is that with rect ports my simulation finds a solution, with coaxial ports it doesn't.. maybe i could try lumped ports, but i think it would go too far from my real model.. Thanks Luca

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