Optimal pump-valve coupling operation strategy of complex long-distance water-conveyance systems based on MOC

Abstract

Transient simulation is crucial for protecting complex pump-valve water conveyance pipeline systems from extreme pressure and water level oscillations. In order to numerically simulate the transient response in a complex pump-valve water conveyance system, a transient flow calculation model was established adopting the method of characteristics (MOC). Based on the proposed model, the transient pressure and the water level fluctuation process were numerically predicted under steady-state operation state, and then the results were compared to the actual measured data. Due to the good agreement between the simulation results and the actual measured data, the model established based on MOC is effective and practical. 41 operational scenario switching schemes were designed according to the uniform experimental design, to study the operation sequence and time differences of pumps and valves during operational scenario switching state. The results show that the operational time interval has a major impact on the transient process under the operational scenario switching state in complex pump-valve systems, and also indicate that delayed pump startup can alleviate the pressure extremum of pipeline systems and effectively control water level fluctuation of such systems. In addition, this study points out the optimal operational sequence and the maximum and minimum allowable time intervals between the pump and the valve under operational scenario switching state in such systems. Finally, an optimized joint operation scheme for pumps and valves with simple operation and small water-level oscillation were proposed under operational scenario switching state.