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Ductulators

These handy devices/programs allow you to calculate Areas, Velocities, Flowrates, Pressure Losses and a load more design criteria either using a simple hand held circular slide rule type device …. or more recently apps for your Android or Apple device. I have …

Moody Diagram

Useful diagram for estimating the relative duct roughness factor in calculating pressure losses in ducts.   It uses the Reynolds Number (Re) a dimensionless number which is obtained from where  is the density of the air at temp and pressures …