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Negative power flow for dipole in free space?

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I am getting a negative power flow in the z-direction (emw.Poavz) at the dipole location. My model is attached. Ignore the nanorods (they've been set to free space). What is going wrong here?


1 Reply Last Post Jun 2, 2014, 2:05 p.m. EDT
Robert Koslover Certified Consultant

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Posted: 1 decade ago Jun 2, 2014, 2:05 p.m. EDT
The quantity emw.Poavz is derived from the RF fields. You are attempting to evaluate it at the center of your dipole, and whether that is a physically-meaningful location is highly-questionable. Even so, the z-component of the average power flow there should evaluate to zero anyway, since the radiated field of a dipole along the z-axis has a null on the z-axis. I'm guessing that you are merely seeing numerical noise.
The quantity emw.Poavz is derived from the RF fields. You are attempting to evaluate it at the center of your dipole, and whether that is a physically-meaningful location is highly-questionable. Even so, the z-component of the average power flow there should evaluate to zero anyway, since the radiated field of a dipole along the z-axis has a null on the z-axis. I'm guessing that you are merely seeing numerical noise.

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