Calculate mean distance from a point to curved line

[sharaborin (Eugene Sharaborin)]

Hello!

I have a highly deformed elongated bubble, and I need to calculate the mean radius along with a bubble.
For this reason:

1. I extract a surface,
   
   
2. take a slice along the bubble (then I have closed curves, the slice can be multiply-connected due to concavities inward)
   
   
3. calculate the mean radius of the slice. Here I don’t know how to do it, Any ideas?
   Thank you in advance!