Toricelli formula

Item Data
Formula Toricelli formula is applied to calculate tank orifice flowrate

Toricelli formula
Supporting drawing Flow of liquid out of a tank through an orifice
Nomenclature Q=Liquid flowrate at orifice (m3/s)
C=Orifice coefficient (-)
A1=Orifice area (m2)

h=Height of liquid from top of tank to middle of orifice (m)

g=gravity acceleration (m.s-2)
Usual values g=9.81 m.s-2
C=0.6 for non profiled orifice
Related Time to empty a tank
Time to empty a tank
tv=Time in s to discharge a tank up to the level of the orifice (s)
H=Height of liquid at t=0 (m)
Source Mecanique et Rheologie des fluides en genie chimique, Noel Midoux, Lavoisier Tec et Doc, page 51