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Modifying Expressions of 4.1 by using expressions of 3.5a

Posted May 31, 2011, 5:58 a.m. EDT RF & Microwave Engineering Version 4.1 3 Replies

Cecil Chalmers
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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 Jun 1, 2011, 12:54 a.m. EDT
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)
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Posted: 1 decade ago May 31, 2011, 11:14 a.m. EDT
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
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Posted: 1 decade ago May 31, 2011, 1:24 p.m. EDT
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)
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Posted: 1 decade ago Jun 1, 2011, 12:54 a.m. EDT
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

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