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Hi,

Here is what I have figured out. I assume you are using the electrostatics module, and that you know how to design your system and assign an electric potential for one electrode and then assign ground for the other electrode. This is for a 2D system. When you run the study for the first time you automatically get a "surface" plot. At the top of your screen you should see "arrow surface", click on it. Disable the "surface" plot and plot the "arrow surface". What you have just plotted is the electric field, NOT the gradient of the electric field. When you plot "arrow surface", it's "settings" tab should automatically pop up. You should see this:

Expression

x component

es.Ex

y component

es.Ey

The "es.Ex" and "es.Ey" are inside editable fields.

Change "es.Ex" to "d((es.Ex)^2+(es.Ey)^2,x)".

Change "es.Ey" to "d((es.Ex)^2+(es.Ey)^2,y)".

Hit "plot". It still might not look like what you are expecting. You should also see this:

Coloring and Style

Arrow length Proportional

Change "Proportional" to "Normalized"

Hit "plot" and now it should look like what you are expecting.

For 3D, you will get one more editable field for the z component.

For 3D, it is called "arrow volume". This will give you a 3D plot of the electric field of your system. Choosing normalized arrows for the electric field will also make it look more like what you are expecting.

For the gradient, change the x and y component just like the 2D example above and then change "es.Ez" to "d((es.Ex)^2+(es.Ey)^2+(es.Ez)^2,z)".