A methodology for calculating hydraulic system reliability of water distribution networks

Mısırdalı, Metin
A completely satisfactory water distribution network should fulfill its basic requirements such as providing the expected quality and quantity of water with the desired residual pressures during its lifetime. A water distribution network should accommodate the abnormal conditions caused by failures. These types of failures can be classified into two groups; mechanical failures and hydraulic failures. Mechanical failure is caused due to malfunctioning of the network elements such as pipe breakage, power outage and pump failure. On the other hand, hydraulic failure, considers system failure due to distributed flow and pressure head which are inadequate at one or more demand points.This study deals with the calculation of the hydraulic system reliability of an existing water distribution network regarding the Modified Chandapillai model while calculating the partially satisfied nodes. A case study was carried out on a part of Ankara Water Distribution Network, N8-1. After the modeling of the network, skeletonization and determination of nodal service areas were carried out. The daily demand curves for the area were drawn using the data that were taken from SCADA of the water utility. The daily demand curves of different days were joined and one representative mean daily demand curve together with the standard deviation values was obtained. The friction coefficient values of the pipes and storage tank water elevation were taken as other uncertainty parameters for the model. Bao and Mays (1990) approach were carried together with the hydraulic network solver program prepared by Nohutcu (2002) based on Modified Chandapillai model. The sensitivity analysis for the effects of system characteristics and model assumptions were carried out to see the effects of the parameters on the calculations and to investigate the way of improving the hydraulic reliability of the network.


Investigation of waterhammer problems in the penstocks of small hydropower plants
Çalamak, Melih; Bozkuş, Zafer; Department of Civil Engineering (2010)
Waterhammer is an unsteady hydraulic problem which is commonly found in closed conduits of hydropower plants, water distribution networks and liquid pipeline systems. Due to either a malfunction of the system or inadequate operation conditions, pipeline may collapse or burst erratically resulting in substantial damages, and human losses in some cases. In this thesis, time dependent flow situations in the penstocks of small hydropower plants are investigated. A software, HAMMER, that utilizes method of chara...
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...
Investigation Of Waterhammer Problems In Çamlidere Dam - İvedik Water Treatment Plant Pipeline At Various Hydraulic Conditions
Sakabaş, Emre; Bozkuş, Zafer; Department of Civil Engineering (2012)
Çamlıdere Dam supplies significant portion of the potable water demand of the City of Ankara. Consequently, it is very important that the pipelines extending over 60 km between the dam and the treatment plant at İvedik operate continuously. At present, two composite parallel lines are in operation and construction of a third line is considered for the future. It is the aim of this study to investigate the water hammer problems to be expected under various scenarios and also suggest the safe operation condit...
Hydraulic characteristics of tyrolean weirs having steel racks and circular-perforated entry
Şahiner, Halit; Göğüş, Mustafa; Department of Civil Engineering (2012)
Tyrolean type water-intake structures are commonly used on mountain rivers to supply water to hydropower stations. The amount of water to be diverted from the main channel is the major concern in these kind of structures and should not be less than the design discharge. In this study a physical model of a Tyrolean type water-intake structure was built at the laboratory and the diverted flow from the main channel through the intake structure having steel racks and perforated plates of different types were me...
Determination of optimum rack angle of tyrolean type water-intake structures
Melek, Abiddin Berhan; Göğüş, Mustafa; Department of Civil Engineering (2017)
Tyrolean weir is known as an effective device to separate major part of sediment from the main channel flow in order to provide required sediment-free water discharge for run-off river hydropower plants. Basically, in the design of Tyrolean weirs, the main concern is to divert at least the design discharge of the facility while it permits to enter the minimum amount of bed-sediment to the system. In this study, water and sediment capture rates of Tyrolean type water-intake structures were investigated for a...
Citation Formats
M. Mısırdalı, “A methodology for calculating hydraulic system reliability of water distribution networks,” M.S. - Master of Science, Middle East Technical University, 2003.