Duct Fitting Database -ashrae 1994- Pdf ((new))

For the first time, engineers could consistently calculate total pressure drop (ΔP_total) using the Darcy-Weisbach equation adapted for fittings: [ \Delta P_fitting = C \cdot P_v = C \cdot \left( \frac\rho V^22 \right) ] Where C is the loss coefficient, ρ is air density (typically 1.204 kg/m³ at 20°C), and V is the average duct velocity.