Diagnostics of Regular Performance of Water Distribution Networks and its Relation to the Network Reliability - Pattern Recognition for Reliability Assessment of Water Distribution Networks - page 191

Table 7.9 Correlation patterns of GA-optimised network at the demand increase of 98% - sn0199

Name V j Q j v j h f,j S j P j T j pb j pb j /L j hl j PBI j

sn019901 0.15 0.48 0.48 0.64 0.70 0.71 -0.03 -0.06 -0.68 0.50 -0.65

sn019902 0.22 0.57 0.57 0.77 0.80 0.83 -0.04 -0.03 -0.79 0.65 -0.78

sn019903 0.28 0.63 0.63 0.85 0.86 0.91 -0.05 -0.01 -0.86 0.76 -0.87

sn019904 0.31 0.66 0.66 0.90 0.89 0.94 -0.05 0.01 -0.89 0.82 -0.91

sn019905 0.33 0.67 0.67 0.92 0.90 0.96 -0.05 0.02 -0.89 0.86 -0.94

sn019906 0.34 0.68 0.68 0.94 0.91 0.97 -0.05 0.04 -0.87 0.88 -0.95

sn019907 0.35 0.69 0.69 0.95 0.91 0.98 -0.05 0.05 -0.84 0.90 -0.96

sn019908 0.36 0.69 0.69 0.95 0.91 0.98 -0.06 0.06 -0.79 0.91 -0.97

sn019909 0.36 0.69 0.69 0.96 0.91 0.99 -0.06 0.08 -0.72 0.92 -0.97

sn019910 0.37 0.69 0.69 0.96 0.91 0.99 -0.06 0.10 -0.62 0.92 -0.98

sn019911 0.37 0.70 0.70 0.97 0.92 0.99 -0.06 0.13 -0.49 0.93 -0.98

sn019912 0.38 0.74 0.74 0.98 0.94 1.00 -0.07 0.19 -0.27 0.94 -0.99

sn019913 0.39 0.82 0.82 0.99 0.98 0.99 -0.09 0.29 0.00 0.94 -0.98

sn019914 0.39 0.86 0.86 0.99 0.99 0.98 -0.11 0.36 0.14 0.93 -0.98

sn019915 0.40 0.87 0.87 0.99 0.99 0.98 -0.09 0.40 0.20 0.93 -0.97

Table 7.10 Correlation patterns of GA-optimised network at the demand increase of 51% - ngt01-151

Name V j Q j v j h f,j S j P j T j pb j pb j /L j hl j PBI j
ngt01-151 -0.10 0.80 0.80 0.95 0.97 0.98 -0.02 -0.16 -0.28 0.89 -0.94
ngt01-151x02 -0.10 0.81 0.81 0.95 0.98 0.98 -0.02 -0.16 -0.26 0.89 -0.94
ngt01-151x03 -0.11 0.82 0.82 0.95 0.98 0.98 -0.02 -0.16 -0.25 0.89 -0.93
ngt01-151x04 -0.11 0.83 0.83 0.96 0.98 0.97 -0.03 -0.15 -0.23 0.90 -0.93
ngt01-151x05 -0.11 0.83 0.83 0.96 0.98 0.97 -0.03 -0.15 -0.21 0.90 -0.93
ngt01-151x06 -0.11 0.84 0.84 0.96 0.99 0.97 -0.04 -0.15 -0.19 0.91 -0.92
ngt01-151x07 -0.11 0.84 0.84 0.96 0.99 0.97 -0.04 -0.14 -0.17 0.91 -0.92
ngt01-151x08 -0.11 0.85 0.85 0.96 0.99 0.97 -0.04 -0.14 -0.15 0.91 -0.92
ngt01-151x09 -0.11 0.85 0.85 0.97 0.99 0.97 -0.04 -0.14 -0.13 0.91 -0.91
ngt01-151x10 -0.11 0.85 0.85 0.97 0.99 0.97 -0.05 -0.13 -0.12 0.91 -0.91
ngt01-151x11 -0.11 0.86 0.86 0.97 0.99 0.97 -0.04 -0.13 -0.10 0.92 -0.90
ngt01-151x12 -0.11 0.86 0.86 0.97 0.99 0.96 -0.01 -0.12 -0.08 0.92 -0.90
ngt01-151x13 -0.11 0.86 0.86 0.97 0.99 0.96 -0.04 -0.12 -0.07 0.92 -0.90
ngt01-151x14 -0.12 0.86 0.86 0.97 0.99 0.96 -0.04 -0.11 -0.06 0.92 -0.89
ngt01-151x15 -0.12 0.87 0.87 0.97 0.99 0.96 -0.03 -0.11 -0.04 0.92 -0.89

All four tables show fairly consistent patterns where in most cases the correlations improve
with the growth of demand. This improvement is faster with the reduction of buffer (Tables
7.9 and 7.11), and shows certain saturation with the increase of stress (Tables 7.8 and 7.10).
These conclusions are not entirely true for the pipe residence time, T j , where the trend of
increase seems to be reversing once the network sn0199 enters the stress conditions, and does
not show clear pattern of correlation in ngt01-151 ; also in this network, the correlation
patterns for (unit) pressure buffer show reverse trend once the minimum pressure starts
dropping below the threshold. This altogether is not quite disturbing because all three
parameters show weak correlations with the loss of demand, in general. The only parameter
that follows the reversed pattern amongst those who correlate better is the pressure buffer
index, PBI j . It is also to be observed that all reverse trends are more visible in the network
ngt01-151 that has much smaller diameters/higher resistance than sn0199 .