Visualization of defects in a 3D vector field as loops

I have a 3D vector field data with a scalar that helps me identify regions in the vector field that are not aligned. I can extract the misaligned region with thresholding the scalar. These regions usually form a closed loop and now I want to render a tube at the cores of the misalignments. Is there a filter that can help with this?
I tried using threshold on a streamline that gives me the normals but unable to render a tube that is perpendicular to the misalignments. Any help would be appreciated.

data.pvsm (566.7 KB)
data.vtu (1.2 MB)

please share a screenshot and data.

Thank you! The data is attached now.


I don’t understand what the physics phenomenon is about, but wouldn’t a Vortex Cores filter help?

When computing the Gradient, you may have a look at the Vorticity option. It will compute a vector field, orthogonal to the gradient and pointing inward / outward vortices. Here is what I obtain with your data:

If you really need to extract one ring and one line, you may be interested in Topological Data Analysis. Using TTK, we have this example that may suits your need, but do not hesitate to ask for some guidance as it is not trivial to use.