Recent content by ashade

  1. A

    Boundary conditions and time domain electromagnetic waves

    Because dumped and undumped solutions cannot equal for all t. Therefore, continuous tangential electric field is not guarateed in the boundary of both media.
  2. A

    Boundary conditions and time domain electromagnetic waves

    I need the field distributions. A transmission line model won't fit because I'm looking for TE and TM modes on a coaxial cable, semi-infinite, with 2 dielectrics: one lossy and the other lossless. And I need distributions of field because I need to find the best way to place some receivers for a...
  3. A

    Boundary conditions and time domain electromagnetic waves

    I insist because A dumped wave does not solve mawell equation for lossless media. Besides, I already tried using time harminic waves to solve my problem. However, I can't solve the proble using real number frequencies. I must be doing something wrong or simply it is not solvable on frequency domain
  4. A

    Boundary conditions and time domain electromagnetic waves

    Andy, do you have any sort of instant messaging software so we could chat about it. You're still missing my point...
  5. A

    Boundary conditions and time domain electromagnetic waves

    actually, confused me a lot! Andy, my apologies, but a damped wave cannot be a solution for wave equation in the lossless media. Its math now, not physics. How can a dumped wave be a solution for \partial^2 E / \partial x^2 = \mu \epsilon \partial E / \partial t
  6. A

    Boundary conditions and time domain electromagnetic waves

    Ok, i think I am not explaining myself clearly. I tried to simplify the problem, but I'll post it entirely here, because I need help. It's for my msc program. I have a structure made by coaxial cylinders of radius a < b. The cylinders are PEC material (perfect electrically conductor)...
  7. A

    Boundary conditions and time domain electromagnetic waves

    That's perfect! for a time harmonic wave. Take a closer look, and you'll find out that your waves are still time harmonic (exp{jwt}). My question is about time domain because I am working with transients. Books assume every wave in the world can be represented by a fouries series expanded using...
  8. A

    Boundary conditions and time domain electromagnetic waves

    Your help was extraordinary. Thankx!
  9. A

    Boundary conditions and time domain electromagnetic waves

    You have a point. However, since I'm assuming no sources, it has no meaning in saying "the incident field is coming from a lossy medium". Moreover, a decaying wave cannot solve Maxwell equation \nabla^2 E_x = \mu \epsilon \partial^2 {E}_x / \partial t^2 - the equation for the lossless media.
  10. A

    Boundary conditions and time domain electromagnetic waves

    I'm keeping a conduction current, not a source current. There's a difference. Anyways, you are wrong: The tangential electric field is discontinuous if, and only if, there is an impressed magnectic current, which is not the case. It has nothing to do with electric charge density. Actually...
  11. A

    Boundary conditions and time domain electromagnetic waves

    I was wrong, the problem is yet not solved. The question is about boundary conditions in the interface of separation of 2 media: one is lossy and the other is lossless. In the lossless media, the wave is non-decaying. In the lossy media, the wave is decaying in time. Since I am assuming...
  12. A

    Boundary conditions and time domain electromagnetic waves

    Sure it can, but it doesn't help answering my question. Diving a little deeper in book "Advanced Engineering Electromgnetics" - Constantine A. Balanis, I ran into the continuity equation, which states: \nabla \cdot (J_i + \sigma E) = -\dot{q_{ev}}. Therefore, since \sigma is not null, there...
  13. A

    Boundary conditions and time domain electromagnetic waves

    You are missing the part that I am assuming a source free media, hence no mobile charges allowed.
  14. A

    Boundary conditions and time domain electromagnetic waves

    actually, equation is: \nabla^{2} E = \mu \sigma \frac{\partial E}{\partial t} + \mu\epsilon \frac{\partial^{2} E}{\partial t ^{2}} Suppose there is only E_{x} , so: E = \hat{a}_{x} E_{x} and equation can be rewriten as \nabla^{2} E_x = \mu \sigma \frac{\partial...
Back
Top