In literature, there are two categories for the analysis of Water Distribution Networks (WDN). The first is Demand Driven Analysis (DDA) at which engineers satisfies the demand at each node and then calculate the pressure in the design of new networks. Softwares like EPANET and other commercial ones comprises the DDA methodologies. Normally, engineers do not take into consideration the sudden events (i.e excessive firefighting demand, excessive demand in some junctions, pipe failure, or pump failure). These events may produce negative pressure problems to the network leading to deficient nodes. In the second category named Pressure Driven Analysis (PDA), researchers attempted to solve the negative pressure problem. Indeed, the PDA methods are treated into three different ways. (i) Modifying the hydraulic solver source code by introducing a new PDA method, or (ii) adding artificial elements like check valve, internal dummy node, flow control valve, reservoir or emitter to network demand nodes, or (iii) adding some of the previous explained artificial elements to demand nodes which are suffering from pressure deficiency. Many researchers try to take into consideration the extended period simulation (EPS) in the water network. Until now, there are many challenges facing researchers to come over the problem of deficient nodes. In this paper, a comparison between results (Demand & Pressure) of a case study when using different PDA methods.

1. Different Methods of Water Distribution Network
Analysis
Arab Academy for Science and Technology and Maritime Transport
College of Engineering and Technology
Construction and Building Engineering Department
Smart Village Branch
Eng. Mohammed Magdy Hamed
Prepared by

2. Serial Network
2
Branched Network
Looped Network

3. Demand Driven Analysis
Theory
Each demand node (DN) takes the
required demand (Qreq)
Then the available pressure (Havl) will
be calculated
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4. Demand Driven Analysis
- Hardy Cross Methods
- Modified Hardy Cross Method
- Newton-Raphson Method
- Linear Theory Method
- Analysis Using Electrical Analyzers
- Analysis through Unsteady Behavior
during Start-Up
- Analysis through Optimization
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5. Problem of Demand Driven Analysis
In Some cases required flow (demand) couldn’t be delivered in each DN
These cases are:
1- Fire Fighting demand
2- Excess use in some DN
3- Pipe failure, pump failure, valve failure…..etc.
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Negative pressure will be arise

6. Pressure Driven Analysis
Developed to address issues of negative pressure estimated by
demand-driven analysis (DDA) solver
Theory:
In each DN
According to the available pressure
The available flow will be calculated
Like the Emitter (sprinkler)
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7. Pressure Driven Analysis
Node Head Flow Relationship
1- Bhave, 1981, 1991
2- Germanopoulos, 1985
3- Salgado-Castro, 1988
4- Wagner et al., 1988
5- Fujiwara & Li, 1998
6- Tanyimboh and Templeman, 2010
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8. 8
PDA Procedures
New PDA methodology
(change source code)
Rossman
(2000b)
Cheung et al.
(2005)
Morley and
Tricarico
(2014)
Elhay et al.
(2015)
Iterative-type approaches
(connect artificial elements)
Ozger and Mays
(2003)
Todini (2006)
Ang and Jowitt
(2006)
Jinesh Babu and
Mohan (2012)
Single iteration-type
(connect artificial elements)
Gorev and
Kodzhespirova
(2013)
Sayyed et al.
(2014, 2015)
Herman (2017)

9. Herman (2017)
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10. Problem Statement
Many Pressure Driven Analysis methods were discussed
since 1981
Till now NO available software (Paid or Free) deal with
PDA with different methods
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11. Bench Mark Example (Ozger & Mays, 2003)
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12. Bench Mark Example (Ozger & Mays, 2003)
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13. Bench Mark Example (Ozger & Mays, 2003)
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14. Future work study
Create a GUI program (MATLAB, C++ or, C sharp)
to compare between the different methods of PDA.
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Thanks!
Any questions?