FCO432 Users Guide Issue 1
Page 27
std
P
Standard pressure in pascals (normally 101325 pascals).
std
T
Standard temperature in kelvin (273.14 + temperature in °C).
T
Temperature of gas in pipe at point of measurement in Kelvin
If the volumetric flow rate at working conditions is required instead of at standard conditions, simply
multiply the velocity by the area and do not make the corrections for pressure and temperature.
Mass Flow:
To calculate the mass flow, the volume flow at standard conditions must be known as well as the
relative density of the gas or the density at standard conditions.
std
m
Q
Q
Where:
m
Q
Mass flow rate in kg/s.
std
Q
Volumetric flow rate in m
3
/s (flow at standard temperature and pressure).
Density of the gas at standard conditions in kg/m
3
.
Density can be calculated by multiplying the relative density by the density of air at standard
conditions (
air = 1.2kg/m
3
@101325Pa, 20°C
).
