# Flow Coefficient calculator, Cv or Kv, for liquids

## Calculator

## Theory

**Metric Units**:

The flow factor, or flow coefficient of a valve shows the relationship between the pressure drop and the flow rate.
K

_{v} is the flow coefficient in

**metric units**, and can be calculated with the following equation:

where

*
K*_{V}: Flow factor (m^{3}·h^{-1}·bar^{-0.5})

Q: Flow rate (m^{3}/h)

SG: Specific Gravity of the liquid (dimensionless). For water SG=1

ΔP: Pressure drop - difference between inlet and outlet pressure - (bar)

**Imperial units**:

In imperial units the flow coefficient is called C

_{V}:

where

*
C*_{V}: Flow coefficient

Q: Flow rate (US gallons per minute)

SG: Specific Gravity of the liquid (dimensionless). For water SG=1

ΔP: Pressure drop - difference between inlet and outlet pressure - (psi)

## Links