Studying of Water Hammer in Water Supply Pipes Network With Different Abnormal Operation Conditions (Case Study - Assiut City Network)

Abstract

This research studies the effect of abnormal operation conditions on water hammer phenomenon in water supply pipe network in order to provide an acceptable level of protection against system failure due to pipes collapse or bursting. Water Hammer and Mass Oscillation WHAMO software is used in the analysis which uses the implicit finite difference scheme for solving the momentum and continuity equations at unsteady state case. Assiut city water supply network is used in the analysis. Flow of pipe network is studied due to; firstly, the sudden change in water demand at one or more junctions, secondly, the closing of some pipes of the network on the transient pressure and flow rates, and finally the failure in some network pipelines on intrusion or leakage due to transient pressure head fluctuations. The previous cases are studied in steady normal case, without any protection, and under different protection device(s) such as non-return valve and open surge tank. The results showed that rapidly change in demand increases the pressure head and flow rate fluctuations. Closing some pipelines increases pressure in a region and decreases it at another and also changes the direction of flow in the network. Also, failure of some pipelines can cause intrusion and leakage from outside the network to inside and inversely, which affects the values of minimum pressure heads more than the maximum ones. Finally, using of open surge tank with nonreturn valve protects the pipe network effectively from the harm water hammer.

Effect of Hydraulic Characteristics on Fluid Transients Analysis under Different Types of Control Valves

“…It was observed from the results, after the appearance of the first pressure wave led to an increase in the pressure head, due to the immediate closure of the valve at the end of the pipeline. Ali et al (2013) studied the effect of a group of factors on water hammer in a network of water supply pipes to provide an acceptable level of protection against system failure as a result of a pipe burst or collapse. It was studied by a program called Water Hammer and Mass Oscillation (WHAMO) to solve the equations of both continuity and momentum for the unsteady state.…”