Experimental and numerical effects of flow hydraulics and pipe geometry on leakage behavior of laboratory water network distribution systems

Abstract. As the leakage behavior of water distribution network is considered life-threatening and critical issue, so the behavior of water distribution network system is investigated experimentally and numerically under the effect of different positions and flow rates of leakage outlets taking into consideretion the flowhydraulics and pipe geametry. A laboratory model of the real studied water distribution network is constructed. The laboratory water distribution network is horizontal and has 16 loops with total length 30 m and different diameters. The leakage position in the laboratory water distribution network is altered between main, sub-main and branch pipelines with different flow rates. The characteristics of the ideal laboratory water distribution network with no-leakage are studied first. The studied laboratory water distribution network system parameters are solved theoretically using Hardy-Cross method with seven iterations. The studied water distribution network system was simulated using computational fluid dynamics technique Ansys Fluent 18.2. The aim is to modify the ancient water distribution network by sensing the pressure values using dispersed pressure sensors. Also, from the pressure map of the laboratory water distribution network, the leakage position if exist can be localized. Depending on the sensed pressure, the control circuit programmed to close the corresponding solenoid valves. The leakage flow rates are 0.1, 0.25 and 0.4 L/s and changed between the main and sub-main pipes. The maximum pressure drop around 500 pa at the node directly preceding the leakage point at leakage flow rate 0.4 L/s. The performance of the used solenoid valve is simulated using Matlab-Simulink technique. The simulation results show the response to step down control signal is over damped with steady state error 2 % and settling time 0.6 s.