Alejandro Lieber wrote
in :

Thank you very much for the explanation.

Another interesting and very practical graph would be: for a 20 turn,
50mm diameter and various winding pitches coil, how much additional
energy loss, 1, 5, 10, 20, 30, 40 additional short circuited turns
add.

Hello Alejandro,

I think the graphs in the article demonstrate that there is a simple
analytical solution, giving the appropriate parameters.

There are issues about the applicability of the model to the real world,
but the model does show trends about what is desirable and undesirable
practice. Wheeler's formula for inductance has its shortcomings
(Wheeler's formula doesn't take into account wire diameter for instance),
but it is (IMHO) sufficiently accurate to expose some of the
'interesting' effects that prompted your initial question.

The model is based on basic electricity and magnetism, stuff that isn't
so appeallng to new age hams.

Owen