I have a simulation after which I am trying to integrate the D-field over an area using template-based post-processing.

Using 2D and 3D field results, I have two options:

(a) Integration over the selected face ---- Using EVALUATE FIELD ON FACE option.

(b) Integration using area/face --- Using EVALUATE FIELD IN ARBITRARY COORDINATES option.

Both these results should be the same. Can anybody help me understand why there is a difference in results?

I have attached pictures depicting both results. The integration using both methods should show the same result. Why are they different?

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