Dear all,

I'm confused about description of womersley number on Page 150 of user-guide-4.4.1. Can anyone give me some suggestions?

On Page 150, for the formulas below:
Screen Shot 2019-06-15 at 5.20.02 PM.png
Screen Shot 2019-06-15 at 5.20.11 PM.png
How can I calculate 'alpha'? Or it is a typo and should be 'alpha_n'?

Also for the formula :
Screen Shot 2019-06-15 at 5.23.19 PM.png,
what  does R and T represent? 
Does R mean RADIUS (the non-dimensional radius of the boundary in Gmsh) or the real radius (with dimension) of the object?
Does T mean Period (the non-dimensional cycle time period)?

Thank you very much!

Best,
Shan