|
...what aerohead was alluding to (from Wiki):
It is the ratio between the area of the jet at the vena contracta to the area of the orifice.
Cc = area at vena contracta/ area of orifice
The typical value may be taken as 0.64 for a sharp orifice (concentric with the flow channel). The smaller the value, the more effect the vena contracta has.
|