Study into water hammer protection of a water supply duct in Movila Verde, Constanta

Human health and well-being are modern day challenges that are directly related to quality of drinking water supply. The study is focused on a newly conceived independent water supply system in Plopeni, which takes water from a good quality underground source, and supplies seven villages either by a series of pumping installations or by gravity. The assessment of hydraulic parameters, energy saving possibilities and the best means to protect the pipes from water hammering are the main goals of the numerical simulation during either the normal or abnormal operation of the water supply duct that carries water from the Plopeni pumping station to the neigh bouring village of Movila Verde. The duct has a specific longitudinal profile that may induce unwanted and dangerous pressure variation during water hammering. The hydraulic parameters and energy consumption indicators were determined by numerical simulation in EPANET. The extreme values of pressure and the most vulnerable cross sections of the pipe during water hammering were identified by numerical simulation with a non-commercial software, named Hammer. The high-pressure values are not dangerous, but cavitation may occur. The hydraulic shock simulation was performed on different methods of protection, provided by closing procedures of the check valve, and considering that the duct is made of steel. The same simulations were considered for a HDPE-made duct of the same inner diameter. The simulation results led to the conclusion that a 60 s two-stages closing procedure proves to be the best solution to protect the steel-made duct from cavitation. In the second simulation, that of a HDPE duct with the same diameter, a 45 s two-stages closing of the check valve provides safe protection from cavitation.