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.

What is the diffrence btw PML and 'scattering boundary condition'?

Please login with a confirmed email address before reporting spam

Setting a subdomain as PML and a boundary condition as scattering boundary can be used alternatively?
I checked it for one tutorial expamle( dielectric scattering PML ) and almost identical result is produced.

2 Replies Last Post 2011年1月12日 GMT-5 18:01
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 2010年12月26日 GMT-5 14:41
Hi

if you read the doc on RF for v4.1 you will get a rather ind epth explanation I believe:

in very short:

A BOUNDARY "port" or a "scattering" condition are to define absorbing/source electric boundaries, in a distributed or a lumped (port) , but in well defined way, this means among other that the wave can travel in both direction from or through the boundary.

While the PML is a DOMAIN feature simulating an infinite domain where ANY wave can propagate and dissapear (without being reflected back)

--
Good luck
Ivar
Hi if you read the doc on RF for v4.1 you will get a rather ind epth explanation I believe: in very short: A BOUNDARY "port" or a "scattering" condition are to define absorbing/source electric boundaries, in a distributed or a lumped (port) , but in well defined way, this means among other that the wave can travel in both direction from or through the boundary. While the PML is a DOMAIN feature simulating an infinite domain where ANY wave can propagate and dissapear (without being reflected back) -- Good luck Ivar

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 2011年1月12日 GMT-5 18:01
Sir

If I want to caculate the Q factor of the whispering gallery mode in the 2D optical circular disk microdisk, what kind of boundary condtion shall I use? The Q factor is just limited to the radiation if I dont consider the absorption of the material .
Another question is shall I use the eigenfrequency analysis to calculate the eigenvalue? After that ,I chose the eigenvalues with small real parts(which with high Q) and calculate the Q factor in the which the imaginary part is divided by the real part. Is the method correct?

Thank you


Hi

if you read the doc on RF for v4.1 you will get a rather ind epth explanation I believe:

in very short:

A BOUNDARY "port" or a "scattering" condition are to define absorbing/source electric boundaries, in a distributed or a lumped (port) , but in well defined way, this means among other that the wave can travel in both direction from or through the boundary.

While the PML is a DOMAIN feature simulating an infinite domain where ANY wave can propagate and dissapear (without being reflected back)

--
Good luck
Ivar


Sir If I want to caculate the Q factor of the whispering gallery mode in the 2D optical circular disk microdisk, what kind of boundary condtion shall I use? The Q factor is just limited to the radiation if I dont consider the absorption of the material . Another question is shall I use the eigenfrequency analysis to calculate the eigenvalue? After that ,I chose the eigenvalues with small real parts(which with high Q) and calculate the Q factor in the which the imaginary part is divided by the real part. Is the method correct? Thank you [QUOTE] Hi if you read the doc on RF for v4.1 you will get a rather ind epth explanation I believe: in very short: A BOUNDARY "port" or a "scattering" condition are to define absorbing/source electric boundaries, in a distributed or a lumped (port) , but in well defined way, this means among other that the wave can travel in both direction from or through the boundary. While the PML is a DOMAIN feature simulating an infinite domain where ANY wave can propagate and dissapear (without being reflected back) -- Good luck Ivar [/QUOTE]

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.