This record describes the ports of a vessel. The variables in it are mostly self-explanatory (see list below); only the ζ loss factors are discussed further. All data is quoted from Idelchik (1994).
If a straight pipe with constant cross section is
mounted flush with the wall, its outlet pressure loss
coefficient will be ζ = 0.5
(Idelchik, p. 160, Diagram
3-1, paragraph 2).
If a straight pipe with constant cross section is
mounted into a vessel such that the entrance into it is at a
distance b
from the wall (inside) the
following table can be used. Herein, δ is the tube wall thickness
(Idelchik, p. 160, Diagram 3-1, paragraph 1).
b / D_hyd | ||||||
---|---|---|---|---|---|---|
0.000 | 0.005 | 0.020 | 0.100 | 0.500-∞ | ||
δ / D_hyd | 0.000 | 0.50 | 0.63 | 0.73 | 0.86 | 1.00 |
0.008 | 0.50 | 0.55 | 0.62 | 0.74 | 0.88 | |
0.016 | 0.50 | 0.51 | 0.55 | 0.64 | 0.77 | |
0.024 | 0.50 | 0.50 | 0.52 | 0.58 | 0.68 | |
0.040 | 0.50 | 0.50 | 0.51 | 0.51 | 0.54 |
If a straight pipe with a circular bellmouth inlet (collector) without baffle is mounted flush with the wall then its pressure loss coefficient can be established from the following table. Herein, r is the radius of the bellmouth inlet surface (Idelchik, p. 164 f., Diagram 3-4, paragraph b)
r / D_hyd | ||||||
---|---|---|---|---|---|---|
0.01 | 0.03 | 0.05 | 0.08 | 0.16 | ≥0.20 | |
ζ | 0.44 | 0.31 | 0.22 | 0.15 | 0.06 | 0.03 |
If a straight pipe with a circular bellmouth inlet (collector) without baffle is mounted at a distance from a wall then its pressure loss coefficient can be established from the following table. Herein, r is the radius of the bellmouth inlet surface (Idelchik, p. 164 f., Diagram 3-4, paragraph a)
r / D_hyd | ||||||
---|---|---|---|---|---|---|
0.01 | 0.03 | 0.05 | 0.08 | 0.16 | ≥0.20 | |
ζ | 0.87 | 0.61 | 0.40 | 0.20 | 0.06 | 0.03 |
If a straight pipe with constant circular cross section
is mounted flush with the wall, its vessel inlet pressure
loss coefficient will be according to the following table
(Idelchik, p. 209 f., Diagram 4-2 with A_port/A_vessel =
0
and Idelchik, p. 640, Diagram 11-1, graph a). According to
the text, m = 9
is appropriate for fully developed
turbulent flow.
m | ||||||
---|---|---|---|---|---|---|
1.0 | 2.0 | 3.0 | 4.0 | 7.0 | 9.0 | |
ζ | 2.70 | 1.50 | 1.25 | 1.15 | 1.06 | 1.04 |
For larger port diameters, relative to the area of the vessel,
the inlet pressure loss coefficient will be according to the
following table (Idelchik, p. 209 f., Diagram 4-2 with m =
7
).
A_port / A_vessel | ||||||
---|---|---|---|---|---|---|
0.0 | 0.1 | 0.2 | 0.4 | 0.6 | 0.8 | |
ζ | 1.04 | 0.84 | 0.67 | 0.39 | 0.18 | 0.06 |