3.7 Head loss due to Transitions and Fittings (Local loss)
Whenever flow velocity changes direction or magnitude in a conduit (e.g., at fittings, bends, and other appurtenances) added turbulence is induced. The energy associated with that turbulence is eventually dissipated into heat that produces a minor head loss, or local (or form) loss. The local (minor) loss associated with a particular fitting can be evaluated by
where V = mean velocity in the conduit (m/s, ft/s)
K = loss coefficient for the particular fitting involved.
The table given below provides the loss coefficients (K) for various transitions and fittings.
Table 3-3: Typical Minor Loss Coefficients
Source: Nicklow and Boulos (2005)