pressure recovery

[gosooners]

For orifice plate, how can I find at what length/distance pressure will recover almost same(considering friction losses) as upstream of orifice plate?

 

[JLSeagull]

ASME MFC-3 sect5ion 7.4 covers pressure loss. I think that both Miller and Spink have information that reflects the permanant loss of a flow orifice plate based upon the beta ratio. I have neither book in my office. The pressure recovery is within six pipe diameters or so downstream of the vena contracta as I read MFC-3M. This is the end of the meter run.

 

[dcasto]

A typical value we use for 100 inches of water is 60% recovery, so that would be a loss of 40 inche or 1.5 psi.

The vena contracta is at about .5 D, by 6 diameters you should be back, thats why orifice meters require about 6 D down stream.