Q3 (30 pts): The three-loop water distribution system shown in the figure below is not functioning
effectively. The demand for water at junction F is being met, but the required pressure by the
industrial customer is 185 kPa. Therefore, the water company has decided to increase the diameter
of one pipe in the network by 5 cm. Determine which pipe should be replaced to have the greatest
impact on the pressure in the system, specifically the pressure at node F. (Hint: examine the output
table for head losses, flow rates, and pipe sizes. One pipe stands out as the best choice, although
there is a second pipe that is only slightly worse.)
Part A: Create an EPANET model for the (unmodified) pipe network presented in the
figure below using the given demands and pipe specifications. Comment on how close your
EPANET results for flow rates and pressures at each node to those presented in the table
below. Please provide some explanation for the possible sources of differences between
the results.
Part B: Using EPANET, replace a pipe of your choice (increase the diameter by 5 cm) and
determine the pressure change at node F. Provide a brief justification for your final desing.
For both parts, please include a screenshot of your final results in the EPANET (i.e.,
showing flows and pressures) model to accompany your discussion. Submit the EPANET
models as part of your .zip folder.
Q=300
Pipe
AB
AD
BC
95
BG
GH
CH
DE
GE
EF
HF
D
205
Flow (m³/sec)
95
0.20
0.10
0.08
0.12
0.02
0.03
0.10
0.00
0.10
0.05
Length (m)
125
300
250
350
125
350
125
300
125
8
E
350
125
B
G
Q = 100
80
Q = 150
Figure 3: Diagram of the water distribution network with the flow rates of each pipe and the
demands at each node.
Diameter (m)
23
Table 2: Properties and flow rates for the pipes in the water distribution system.
0.30
0.25
0.20
0.20
0.20
0.20
0.20
0.15
0.20
0.15
33
3
87
30
elD
63
0.00087
0.00104
0.00130
0.00130
0.00130
0.00130
0.00130
0.00173
0.00130
0.00173
Q = 50
H
ƒ
0.019
0.020
0.021
0.021
0.021
0.021
0.021
0.022
0.021
0.022
K (sec²/m³)
194
423
1,900
678
1,900
678
1.630
2,990
1,900
2,990
