Minor (Fitting) Head Loss

h_{m} = K \frac{V ^{2}}{2 g}

Each fitting, valve, entrance, or exit has a loss coefficient K from Handbook tables. hm is added to pipe friction hf = f (L/D) V²/2g. Use the velocity in the pipe to which K is referenced.

$K$: Loss coefficient
$V$ (m/s): Reference velocity
$h_{m}$ (m): Minor loss

Step-by-step solved example

K=0.50, V=4.0 m/s. hm? g=9.81.

Each fitting: hm = K V²/2g. Add along the pipeline.

1. V²/2g
16/(19.62)=0.815 m.
2. hm
hm=0.50×0.815=0.408 m.
$h_{m} = 0.408 m$

Answer: 0.408 m

10 practice questions

0/10 correct

1.hm equals

2.A larger K means

3.Sudden expansion K is

4.Pipe friction is a major loss: hf=

5.Entrance from a tank (reentrant) K is typically

6.Exit into a large tank K is

7.V=3 m/s, K=2, g=9.81. hm nearest

8.Valves: a fully open gate has

9.Total head loss is

10.K is dimensionless because