Causes of Surge
Effects of Surge
Surge Analysis Procedure
Building of Network Model
This includes the definition of pipe alignment, pipeline attributes (type, diameter and friction coefficient), location of fittings and their attributes.
Allocation of Water Demand
The Water Demand will be assigned to relevant segments of the pipeline.
Steady State Simulation
Steady State Simulation is necessary to enable calibration of the model.
Extended Period Simulation
Extended Period Simulation is necessary to gauge the impact of a Transient Event on the Network.
Estimation of Transient Events
- Method of Characteristics (MOC): Uses ordinary differential equations derived from partial differential equations for the estimation of transient events.
- Wave Characteristic Method (WCM): Based on the premise that transient events that occur because of a disturbance in the pipeline system lead to the generation and propagation of pressure waves.
Surge Mitigation
The effects of Surge events can be reduced by providing requisite appurtenances along the pipeline section.
Surge Protection- Appurtenances
- Non- Return Valves (Check Valves)
- Bypass pipework especially at Booster Pumping Stations
- Relief Valves: Pressure Relief Valves (PRVs), Surge Anticipation Valves and Rupture Disks
- Air Valves: Non-Slam Air Valves, Dynamic Combination Air Valves and Vacuum Breakers
- Feeder Tanks to boost pressures in the system.
- Surge Shafts/ Standpipes which extend above the Hydraulic Gradient Line (HGL)
- Surge Vessels
