الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
This thesis focuses on the water distribution networks in unsteady state condition. Problems of water hammer associated with surge waves may be destructive.To study these problems a case study of Bosat Kareem El-Dien was selected. The case study was examined in both steady state and unsteady state conditions. Water hammer phenomenon due to transient flow was studied in this research work. Bosat Kareem El- Dien water network was selected as a case study. Field data concerning Bosat Kareem El-Dien network were collected. Six paths (all paths) deliver filtered water from the pump station of this network have been chosen to study the water hammer phenomenon. These paths have different lengths, pipe diameters, materials and discharges. Bentley Water Hammer model Vi 8 was applied to study the pressure variations due to the surge wave resulting from this phenomenon and to find the best device for the water hammer protection. Steady state conditions in Bosat Kareem El- Dien water network should be studied before applying the Water Hammer model. Water Gems software was used for this purpose.Simplification of the network is carried out for eliminating the ineffective elements, such as small networks of villages and cities (internal network) which have no effect on the output data for network main lines. Simplification facilitates the computation and reduces the computing time. Different trials have been done to adjust the discharge in every pipe and pressure for every node of this network in order to get almost the same values before simplification. Numbers of pipes and nodes before simplification are 6099 and 5681 reactively and after simplification 1849 and 1632 reactively. The case of sudden failure and simultaneous sudden restart of the pump station gives the worst condition for the water hammer in Bosat Kareem El-Dien network. This case may lead to positive hydraulic gradient of 130 m and negative head of -10 m. Air vessel of volume 20 m3 and with water air ratio of 67 % is more suitable for protection of Bosat Kareem El- Dien water pipe network against pressure surge wave due to water transient flow. Three hypothetical pipe networks similar to Bosat Kareem El-Dien are tested but having different pipe materials for the whole network, PVC, Cast Iron and Steel. The results are compared and show that the PVC pipe network gives more resistance to the hammer and no need for protection. Almost both cast iron and steel pipe networks give the same results and protection is required.