Need help with parameters

[tania-19]

Hi!
I am trying to run vortexFitting with this data.

If I display the vorticity it is pretty good.

But, when trying to fit the vortex I can only do it if I put threshold of 0.7. The fit of this vortex is not good because it is not a perfect circle?

Besides, when using a set of image the information is shared between images? or it only repeat the same procedure to every image?

[ydevau01]

Hello !

Yes, the threshold is low, because of the shape of the vortex. If your flow is sheared in one direction, the vortices are not perfectly circular, but ellipsoidal. So, the correlation value decreases. Have you already subtract the average field ?
It is a possibility of improvement, to modify the Lamb-Oseen model to fit uncircular vortices !

When you use a set of images, the same procedure is repeated yes. In the future, we want to add this feature too, using the information from a first file to track more efficiently the vortices in the next step.