Environmental Engineering Reference
In-Depth Information
7.2.4 Network Diagnostics Tool
To be able to check the correlations of the proposed measures, the network diagnostics tool
(NDT) used in the analyses done in Chapter 6 has been expanded with additional results,
namely:
1.
network residence time (
NRT
),
2.
network power input (
P
i
),
3.
network power loss (
P
l
),
4.
total residual power in discharge points (
P
r
),
5.
network power index (
NPI
),
6.
network pressure buffer (
pb
n
),
7.
network friction loss (
hl
n
),
8.
pressure buffer index (
PBI
),
All the additional measures can be calculated both in the demand-driven (DD) and pressure-
driven demand (PDD) mode. The PDD calculations done for single network include the
values of residence time, power loss, pressure buffer, and pressure loss for each pipe.
7.3
SIMULATION RUNS
The simulation runs have been executed on a sample of ten networks of different properties,
selected from the batches used in the analyses in Chapter 6. The properties of the networks
are given in Table 7.1 and the layouts shown in Figure 7.2.
Table 7.1
Synthetic networks used for comparison of reliability measures
No.
Name
Nodes Links Loops
L
tot
V
tot
Q
pdd
D range
p/ρg range
H
s
/ z range
(-)
(-)
(-)
(km)
(m
3
)
(l/s)
(mm)
(mwc)
(msl)
1
sn73
77
79
3
10.4 2045
3179 500 fixed
20-81
160 / 50 fixed
2
sn80
77
109
33
16.0 3142 4210 500 fixed
20-37
160 / 50 fixed
3 O20sn73
77
79
3
10.4
740 2280 100-650
20-97
160 / 50 fixed
4 O20sn80
77
109
33
16.0
824 2280 100-750
20-101
160 / 50 fixed
5
sn0179
77
79
3
11.3 2214 2044 500 fixed
20-48
160 / 50 fixed
6
sn0199
77
99
23
13.4 2630 4127 500 fixed
20-45
160 / 50 fixed
7
sn0109
77
109
33
18.4 3618 2011 500 fixed
20-57
160 / 50 fixed
8 ngt01-50
50
66
17
77.4
608
15 100 fixed
20-49
60 / 0.2-18.8
9 ngt01-151
151
233
83 254.5
1999
15 100 fixed
20-41
60 / 0.2-20
10 ngt01-200
200
299
100 290.9 2285
19 100 fixed
20-47
60 / 0.2-19.8
These networks have been selected to provide a variety of connectivity, demands, pressures
and pipe resistances. The
O20sn73
and
O20sn80
are the versions of
sn73
and
sn80
with GA-
optimised pipe diameters for the minimum pressure of 20 mwc. In all other networks, the
diameter has been kept fixed with the demands adjusted to satisfy the same pressure
threshold. The last three networks have pipes with considerably longer lengths and smaller
diameters. Also, the nodal elevations have been randomly generated in these networks.
Finally, the pipe roughness value of 0.5 mm has been used in all the cases.
Search WWH ::
Custom Search