Pressure drop in a closed piping system

[BPLBPL]

Hi all, this may be a trivial/dumb question. I have a simple, closed hydronic system of 2" pipe dia. with a SS tank in the loop. I'm trying to select a pump for this closed system.

Tank dimensions = 16' length, 5' diameter
System flow rate = 5 gpm
System pressure = 12 psig

The question is, how do I calculate the (approx)PRESSURE LOSS due to friction in the tank? I know I should be using the Darcy-Weisbach relation to calculate pressure losses in pipings; can I use the same to calculate pressure drop in the tank as well?

Also, any book recommendations for designing storage tanks? Thank you.
Baggi

 

[Latexman]

The velocity of 5 gpm in a 5' diameter tank is extremely low and the friction loss calculated by Darcy-Weisbach will be nil. It is common practice to characterize the losses of a tank in a closed loop as one velocity head (K = 1) for the sudden enlargement where liquid is returned to the tank and 1/2 a velocity head (K = 1/2) for the sudden contraction where liquid exits the tank to go to the pump.

Good luck,
Latexman

 

[Artisi]

The entry and exit losses in the tank would not even be worth considering unless you need to know purely for an academic consideration, if this is the case refer to Latexman's posting.

 

[BPLBPL]

Latexman & Artisi: Thanks a lot for the reply.