Flow Calculation

For each solenoid valve is indicate the flow coefficent Kv.
With this data it is possible to calculate the flow. Known the loss of flowing pressure (pressure drop),
the media type and the working pressure it’s possible to calculate the rate flow.
This coefficent of flow is determined by way of experimentation to the standard VDE 2173 and represents
the discharge of water from the solenoid valve with a pressure difference of 1bar
at temperatures between 5°C and 40°C.

Kv = m3/h	Flow coeffient
Q = m3/h	Flow
Qn = m3n/h	Normal flow (20°C 760mm Hg)
P1 = bar	Inlet pressure (Gauge pressure + 1)
P2 = bar	Outlet pressure (Gauge pressure – 1)
DP = bar	Pressure drop (Differential  pressure between inlet and outlet pressure)
r = Kg/dm³	Relative density with respect to water (Water at 4°C = 1)
rn = Kg/dm³	Normal relative density as to the air
G = Kg/h	Mass
t = °C	Inlet media temperature
V1 = m3/Kg	Inlet specific volume
V2 = m3/Kg	Outlet specific volume referred to “P2” pressure and “t” temperature