32 Pipe Flow Expert Example Systems

General 11 - Replacement Pipe Size

Figure 26 General 11 - Replacement Pipe Size

Water is being transferred from an upper reservoir to a reservoir at a lower level using the difference in fluid head between the surface elevations as the motive force. The existing system uses 12", 10" and 8" steel pipes. The 10" and 8" steel pipes carry the water flow in parallel to each other.

The elevation of the nodes, N2, N3 and N5 do not affect the flow rate calculations, which are ultimately determined by the difference in head between the source reservoir and destination reservoir.

Proposed replacement (PVC pipe):

It is proposed to replace the leaking system with new PVC (AWWA) pipe. The friction loss in PVC pipe is much lower than the friction in steel pipe so the 10" and 8" pipes can be replaced with a single 12" PVC pipe in the new system.

The new PVC pipe system will have an increase in carrying capacity of approx 12%.