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.
induced charge density
Posted Apr 4, 2016, 3:33 a.m. EDT RF & Microwave Engineering 2 Replies
Please login with a confirmed email address before reporting spam
Hello everyone,
I am working with the RF module of the Comsol 4.3b version. I am trying to calculated the dipole moments (px, py, pz) of a split ring resonator (SRR) illuminated by a plane wave. For calculating the dipole moment in x, I need to do the following:
px = VolumeIntegral(r_x rho(r) dv)
here, rho(r) is the induced charge density and r_x is the x-coordinate of the split ring resonator.
I am trying to reproduce the results from a paper but I have the feeling that I am doing something wrong during the post processing, where I try to calculate the volume integral of current density norm.J as I do not know how I could get the following parameters from Comsol.
1. r_x, which is the x-coordinates inside the volume of the split-ring resonator only.
2. the induced charge density, rho(r)
I would be grateful if any soul out there has any idea how to approach this problem and could help me. Maybe Ivar? I have always found your insights very educational.
Thanks in advance :)
I am working with the RF module of the Comsol 4.3b version. I am trying to calculated the dipole moments (px, py, pz) of a split ring resonator (SRR) illuminated by a plane wave. For calculating the dipole moment in x, I need to do the following:
px = VolumeIntegral(r_x rho(r) dv)
here, rho(r) is the induced charge density and r_x is the x-coordinate of the split ring resonator.
I am trying to reproduce the results from a paper but I have the feeling that I am doing something wrong during the post processing, where I try to calculate the volume integral of current density norm.J as I do not know how I could get the following parameters from Comsol.
1. r_x, which is the x-coordinates inside the volume of the split-ring resonator only.
2. the induced charge density, rho(r)
I would be grateful if any soul out there has any idea how to approach this problem and could help me. Maybe Ivar? I have always found your insights very educational.
Thanks in advance :)
2 Replies Last Post Apr 29, 2016, 1:41 a.m. EDT
Please login with a confirmed email address before reporting spam
Posted:
9 years ago
If I understand you correctly, you seek to carry out an integral over one or more of your domains, of a computed quantity. If the "volume of the split-ring resonator only" corresponds to one or more such domains, you can do this in a variety of ways. Here's one approach.
In the Model Builder, under Component, right-click Definitions, select Probes --> Domain Probe. Choose probe type as Integral. And chose the domains you want (under selection) and the integrand you want where it says "Expression." Name and label the quantity whatever you want (e.g., MyDipoleMoment).
The rest of what you need to do should be relatively clear.
p.s. My answer applies to Comsol 5.x I apologize if it is different in 4.x
In the Model Builder, under Component, right-click Definitions, select Probes --> Domain Probe. Choose probe type as Integral. And chose the domains you want (under selection) and the integrand you want where it says "Expression." Name and label the quantity whatever you want (e.g., MyDipoleMoment).
The rest of what you need to do should be relatively clear.
p.s. My answer applies to Comsol 5.x I apologize if it is different in 4.x
Please login with a confirmed email address before reporting spam
Posted:
9 years ago
Hi ajeetraj,
I have some experiences in this problem. In RF module, it seems you can not get the induced charge density. Fortunately, you can get the induced current density. Then px = VolumeIntegral(r_x rho(r) dv) can be changed to px = VolumeIntegral(-1i/omega*Jx dv), where Jx is the x directional induced current density. Then you simply integrate the current density and get the results.
Regards,
Zhang
I have some experiences in this problem. In RF module, it seems you can not get the induced charge density. Fortunately, you can get the induced current density. Then px = VolumeIntegral(r_x rho(r) dv) can be changed to px = VolumeIntegral(-1i/omega*Jx dv), where Jx is the x directional induced current density. Then you simply integrate the current density and get the results.
Regards,
Zhang