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 The information provided may be out of date.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.

Modifying Expressions of 4.1 by using expressions of 3.5a

Posted 2011年5月31日 GMT-4 05:58 RF & Microwave Engineering Version 4.1 3 Replies

Cecil Chalmers
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Dear Users,
I am new to Comsol 4.1. I had some problem in the expressions. Before i was using 3.5a but now i switched to 4.1. Here some of the variables are different due to which i have some problems in the expressions. The expressions of 3.5a are given below. I need some help to modify it into 4.1.


ofact if(nx*x+ny*y+nz*z>=0,1,-1) Sign factor for outward normals on interior boundaries
onx nx*ofact Outward normal on interior boundaries, x-component
ony ny*ofact Outward normal on interior boundaries, y-component
onz nz*ofact Outward normal on interior boundaries, z-component
P0 0.5*E0^2*c0_rfw*epsilon0_rfw Incident flux
scPoxav 0.5*real(scEy*conj(scHz)-scEz*conj(scHy)) Scattered flux, x-component
scPoyav 0.5*real(scEz*conj(scHx)-scEx*conj(scHz)) Scattered flux, y-component
scPozav 0.5*real(scEx*conj(scHy)-scEy*conj(scHx)) Scattered flux, z-component
nscPoav onx*scPoxav+ony*scPoyav+onz*scPozav Scattered normal flux
nPoav onx*Poxav_rfw+ony*Poyav_rfw+onz*Pozav_rfw Total normal flux on interior boundaries
r sqrt(x^2+y^2+z^2) Radius-vector
dsigma_near nscPoav/P0*r^2 Differential scattering cross-section, near-field definition
dsigma_far (normEfar^2/(r/1[m])^2)/abs(E0)^2*r^2 Differential scattering cross-section, far-field definition
sigma_ext_near sigma_near+sigma_abs Total extinction cross-section, near-field calculation
sigma_scat_OT sigma_ext_OT-sigma_abs Total scattering cross-section, Optical Theorem calculation


BR,

Cecil
3 Replies Last Post 2011年6月1日 GMT-4 00:54
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 2011年5月31日 GMT-4 11:14
Hi

not fully obvious, here are a few general comments

expressions in 3.5 are now called Varaibles, just as Constants 3.5 are now Parameter (and work also for geoemtry) this translations are listed in the new 4.2 doc

all "_rfw" suffix are now "rf." prefixes

Physical constants have the suffix "_const" i.e epsilon0_rfw is epsilon0_const


Then turn on the "equation view" in the preferences to help your way trough the new variables (there are many ;)

--
Good luck
Ivar
Hi not fully obvious, here are a few general comments expressions in 3.5 are now called Varaibles, just as Constants 3.5 are now Parameter (and work also for geoemtry) this translations are listed in the new 4.2 doc all "_rfw" suffix are now "rf." prefixes Physical constants have the suffix "_const" i.e epsilon0_rfw is epsilon0_const Then turn on the "equation view" in the preferences to help your way trough the new variables (there are many ;) -- Good luck Ivar
Cecil Chalmers
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 2011年5月31日 GMT-4 13:24
Hi,
Thanks for your help.

Can you share with me the new translation (as you mentioned that it is listed in 4.2 doc) of these expressions?

BR
Cecil
Hi, Thanks for your help. Can you share with me the new translation (as you mentioned that it is listed in 4.2 doc) of these expressions? BR Cecil
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 2011年6月1日 GMT-4 00:54
Hi

sorry but that covers a few pages, ask your rep to speed up the 4.2 shipment, the doc has gained a few thousand pages too ;)

--
Good luck
Ivar
Hi sorry but that covers a few pages, ask your rep to speed up the 4.2 shipment, the doc has gained a few thousand pages too ;) -- Good luck Ivar

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