The manual utilizes the Reynolds number to determine the fluid's flow regime. This dimensionless value quantifies the ratio of inertial forces to viscous forces: Laminar Flow (
It is a standard engineering reference (often called or formally “Engineering Data Book — Pipe Friction” ) published by the Hydraulic Institute (HI) . It provides friction loss data for fluids flowing in pipes, valves, and fittings. hydraulic institute pipe friction manual pdf