Calcolatore Coefficiente di Portanza — Formula

HVAC Duct Sizing

Duct size is determined by the airflow requirement and an acceptable air velocity.

Formula

A = Q / V (required area)

D = sqrt(4Q / (pi V)) (circular duct diameter)

where Q is airflow in m^3/s and V is maximum velocity in m/s. Higher velocity means smaller ducts but more noise and pressure drop.

Esempio Risolto

300 L/s airflow with 6 m/s maximum velocity.

  1. Q = 300 L/s = 0.30 m^3/s
  2. A = 0.30 / 6 = 0.05 m^2 = 50,000 mm^2
  3. D = sqrt(4 x 0.30 / (pi x 6)) x 1000 = sqrt(0.0637) x 1000 = 252 mm
  4. Round up to next standard size: 250 or 300 mm duct.