5th Arab Water Week 2019

1. 5th Arab Water Week 2019 March 2019 Pressure-Dependent Supply Modeling: An Effective Tool for Water Equality, Pressure and Leakage Management in An Intermittent Supply System Eng. Meifa Chen, PhD Eng. Luba Hamdi

2. Presentation Outline Pressure-Dependent Supply (PDS) What Is PDS? What is PDS Modeling? Why Is PDS Modeling Important? How Does PDS Modeling Help Manage Supply Equality, Pressure Management and Leakage Management? Case Study

3. What Is Pressure-Dependent Supply? Sufficient pressure to fill tank for one-week consumption Insufficient pressure to fill tank. Customer will have shortage for one-week consumption.

4. What Is Pressure-Dependent Supply? It is a water supply mode when there is not sufficient water to meet the water needs of the customers. Therefore, water is supplied intermittently rather than continuously. To have water for non-supply time, customers install tanks at their buildings to store water. The amount of water they receive depends on pressure, supply time and their tank volume. Therefore, the supply is pressure dependent. During supply time, customers at advantageous locations experience higher pressure at their connections. Hence, their tanks are filled faster and they are more likely to have sufficient water. Customers at disadvantageous locations experience lower pressure at their connections. Hence their tanks are filled slower and they are less likely to have water. Customers may or may not receive the amount of water they need depending on the pressures at their connections.

5. What Is Pressure-Dependent Supply Modeling? Source: SewerGEMS Help Outflow at a demand node is a function of the pressure at that node based on an equation or a lookup table. Q

6. Capacity of Tank Nozzle • = = (SI Units) • = (SI Units, Assuming C = 0.5) • = (Q – l/s, P - m)

7. Verification Experiment by Tom Walski et al Source: Tom Walski, Devin Blakley, Matthew Evans, Brian Whitman, “Verifying pressure dependent demand modeling”, XVIII International Conference on Water Distribution Systems Analysis, WDSA2016.

8. Verification Experiment by Tom Walski et al Source: Tom Walski, Devin Blakley, Matthew Evans, Brian Whitman, “Verifying pressure dependent demand modeling”, XVIII International Conference on Water Distribution Systems Analysis, WDSA2016.

9. Why Is Pressure-Dependent Supply Modeling Important? It simulates a supply-driven system more accurately than the conventional demand-driven modeling. It can help better design or configure a supply-driven system. It can be used to effectively manage water equality, pressure and leakage in a supply-driven system. It can help develop supply schedule for better pressure and leakage management.

10. Supply-Driven Systems Are Popular Worldwide

11. Case Study Reservoir

12. Pressure (m)EPS, Demand Driven, Diurnal Curve

13. Pressure (m)Steady State, Demand Driven, Peaking Factor=1

14. Pressure (m)Steady State, Demand Driven, Peaking Factor=2

15. Pressure (m)Steady State, Demand Driven, Peaking Factor=3

16. Pressure (m)Steady State, Demand Driven, Peaking Factor=4

17. Pressure (m)Steady State, Demand Driven, Peaking Factor=5

18. Pressure (m)Steady State, Demand Driven, Peaking Factor=6

19. Pressure (m)Steady State, Supply Driven, Peaking Factor=6

20. Pressure (m)Steady State, Demand Driven, Peaking Factor=7

21. Pressure (m)Steady State, Supply Driven, Peaking Factor=7

22. Demand Shortage (m3/d)Steady State, Supply Driven, Peaking Factor=6

23. Demand Shortage (m3/d)Steady State, Supply Driven, Peaking Factor=7

24. Thank you!