In this offshore oil rig near Norway, the initial stages of the firewater safety system needed to be modelled in order to calculate the flowrates at pump startup, checking for occurrence of water hammer.
The aim of the model was to minimise design time, therefore the whole deluge system was not modelled in its entirety. Instead, as can be seen, pairs of operating valves were used to model the deluge system. The pressure in the ringmain under normal operation is 19.3 barg. When the pumps are off, the pressure is maintained by the jockey pump, which is always operational.