Learning Forum

[sagar]

I did the sweep and was able to visualize the transmission profile but could not get anything for the electric field with the mesh. But without adding mess it was working fine. What should I do to fix the problem? please suggest. Thank you!

[Kyle]

This issue is discussed in this topic: /forum/discussion/34980/unable-to-visualize-the-sweep-results-for-electric-field-and-magnetic-field#latest
As mentioned in that post, this is due to the mesh spacing over the monitor changing between each iteration of the simulation. This means the results cannot be combined into one dataset. The files from the individual simulations are saved by the sweep utility in a subfolder, so you can view the field results in the monitors in the individual files, but you can't view a combined dataset in the main file where the parameter sweep was run.
To fix this, the mesh over the monitor needs to be constant between the iterations in the sweep. You can try to do this using a mesh override region. Does the mesh override region you added cover the entire monitor? If it doesn't, try extending the mesh override region to extend beyond the monitor, covering some extra space outside the monitor as well.

[sagar]

What I did in this simulation was, I placed a mesh overwrite region around the pillar and varied the Xspan by doing a sweep, so each time mesh area was also increasing.
According to you, as mesh overwrite region size is changing over the sweep. Is it the problem? It should not change over time? I need some clarification.

[Kyle]

The monitor will save electric field data at each of the mesh points contained in the span of the monitor. It is saved as a dataset with Ex, Ey, and Ez field data as well as x, y, and z vectors corresponding to the locations of the mesh points in the simulation. When you run a parameter sweep it will try to combine the E field datasets together into a single dataset, but it can't do this if the size of the E field data or the x, y and z vectors are changing.
In other words, the mesh inside the span of the monitor can't change if you want the E field results to be saved in one dataset by the parameter sweep. Changing the size of the mesh override region will change the mesh inside the monitor. The automatic meshing algorithm will place more mesh points inside a volume with a higher refractive index, so changing the structure will also change the mesh. The simplest way to prevent this would probably be to use a uniform mesh:
Usually the E field data itself isn't saved as a result of the parameter sweep so this isn't a problem. Instead, the post-processing is done in an analysis group or monitor and the results from those are saved by the parameter sweep.