Considerations on multiobjective optimization regarding municipal water supply systems

Download

12625931.pdf

Date

2020-9

Author

Bektaş, Hayrettin Onur

Metadata

Show full item record

Item Usage Stats

326
views

510
downloads

Optimal water supply system design has always been a challenge for researchers. While most optimization studies focus mainly on pipe diameter sizing, recent works are being done for optimizing other elements of water supply systems. The design of water supply system can be discussed from either single or multiobjective optimization point of view. Multiobjective optimization does not only consider the costs of the system but also some performance measures such as resilience. In this study, a multiobjective optimization methodology is developed by using non-dominated sorting genetic algorithms (NSGA-II). Consequently, Pareto trade-off curves for cost vs. network resilience (In) are obtained. Different sets of solutions are formed with different population sizes; then performances are measured by hypervolume calculations to determine optimum population size for the system considered. Finally, one solution is selected within the pareto curve by compromise programming to offer a design to the decision maker. Shamir network, Hanoi network and a real distribution network from Ankara are studied as case studies. It is concluded that constraints play a decisive role on pareto curves in the methodology. When number of constraints are increased, final pareto curve shifts away from the true pareto curve. Moreover, it is observed that, placing storage tanks in the system have less effect on the network strength when compared to diameter changes. It is also concluded that a storage tank count limitation is present in Shamir and Hanoi networks. After this case specific limit, it becomes very hard to place another feasible tank to the network and final pareto curves consist of very few points.

Subject Keywords

Multiobjective Optimization, NSGA-II, Network Resilience, Optimum Water Distribution System Design, Ankara

URI

https://hdl.handle.net/11511/69040

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Design of looped water distribution networks using a heuristic approach Ateş, Halil İbrahim; Merzi, Nuri.; Department of Civil Engineering (2019) This study aims to design pipe diameters of a water distribution network using a heuristic approach algorithm. The heuristic approach algorithm aims to maximize the reliability of the network while minimizing the total cost of the water distribution network, which is a multi-objective optimization problem. In a water distribution network, the resilience index is defined as network reliability (Todini, 2000). The cost of the water distribution network is the total cost of the network pipes. In this heuristic...
New methodologies for optimal operation of water distribution systems for water quality purposes Altan Sakarya, Ayşe Burcu; Mays, LW (1998-01-01) Two new methodologies have been developed for determining the optimal operation of water distribution systems for water quality purposes. These methodologies are based upon describing the operation as a discrete time optimal control problem that can be used to determine the optimal operation schedules of the pumps in distribution systems. One solution methodology is based upon a mathematical programming approach and the second methodology is based upon a simulated annealing approach. These two methodologies...
Developing a methodology for finding network water losses using information technologies Bektaş, Hayrettin Onur; Merzi, Nuri; Akyürek, Sevda Zuhal; Department of Geodetic and Geographical Information Technologies (2010) This study aims to develop an integrated methodology for finding water leaks in a water distribution network. The integrated methodology is formed from SCADA System, Customer Information System (CIS), and Geographic Information System. The methodology is based on forming district-metered areas (DMA) and sub-DMAs in pressure zones by isolation of the network. Leaking spots in the network are localised by step testing within the DMA. With leak noise loggers leaking spots are localized with an increased accura...
A Methodology for Optimal Layout Design of Pressure Cells for Concrete Faced Rockfill Dams Arı, Onur; Yanmaz, Ali Melih (Springer Science and Business Media LLC, 2018-08-01) In this study, a methodology for optimal layout design of pressure cells for concrete faced rockfill dams is developed. A representative dimensionless stress distribution model was formed for obtaining the magnitudes and location of different stress zones as a function of dam height. This information enabled development of a procedure for proper location and the number of pressure cells throughout the dam body. A vertical placement algorithm based on error minimization was first developed, which is followed...
A methodology to assess suitability of a site for small scale wet and dry CSP systems Uzgoren, Eray; Timur, Eray (2015-06-25) This study presents a methodology to assess suitability of a site for small scale concentrated solar power (CSP) systems for its energy conversion efficiency and make-up water requirement. Energy conversion efficiency of CSPs relies not only on the level of direct solar radiation but also on the performance of the cooling system. Regions with high solar potential have to deal with heat rejection at elevated temperatures which causes reduced energy conversion efficiencies due to high condenser temperatures. ...

Citation Formats

H. O. Bektaş, “Considerations on multiobjective optimization regarding municipal water supply systems,” Ph.D. - Doctoral Program, Middle East Technical University, 2020.