Sensitivity Analysis for the Resistance on the Performance of a Pressure Vessel for Water Hammer Protection

Pressure vessels can greatly protect a water supply pipeline system from water hammer damages. In order to improve the performance of a pressure vessel, a strainer is proposed to compensate the resistance of the connecting pipe. A numerical model and program is established for a pressure vessel with an independent compensation strainer based on the method of characteristics (MOC). Using the proposed model, the hydraulic transient processes are simulated for a pressure vessel with various strainer resistances, and the hydraulic pressure and volume fluctuations are obtained by the proposed model. The influences of resistance on the transient process are analyzed and an optimal approach is suggested to determine the suitable compensation strainer for the pressure vessel. A water hammer protection system is optimized based on the proposed method. The result shows that the compensation strainer can largely affect both positive and negative water hammer pressure. If a suitable strainer is selected based on the proposed approach, the transient surge and extreme pressure distribution will decrease. To some degree, it is simple and convenient to improve a pressure vessel by employing an additional compensation strainer in the pipeline system for water hammer protection.