Ventilation of a substation
Entrance area
\[ S_{E} = \frac{W_{CU}+W_{FE}}{0.24·K· \sqrt{h·ΔT^3} } \]
\[ S_{E} = 0.73 · S_{O} \]
· SE: Entrance area, m
· WCU+FE: Copper and vacuum losses, kW
· K: Coefficient as a function of the grid area
· h: Vertical center-to-center distance of air vents (inlet and outlet), m
· ΔT³: Temperature difference between supply and exhaust air, ºC
· SO: Output surface, m
Calculation of required flow rate:
· Pressure (P): 101,325 Pa
· Constant R (air): 287.05 J/kg·K
· Ce (air): 1,012 J/kg·K
Density of the air (consider ideal gas P·V = n·Rg·T)
\[ \delta \frac{kg}{m^3} = \frac{P_{AIR}}{R · T} \]Outlet flow rate:
\[ Q_{O} = \frac{W_{CU}+W_{FE}}{\delta·C_{E}·ΔT} \]· QO: Outlet flow rate, m³/s o m³/h
· ẟ: Air density, kg/m³
