Modelling of water demand in distribution networks

Abstract

The allocation of water demand to nodes is compared with uniformly distributed demand along a pipeline, and it is shown that the nodal approach produces an upper bound or unsafe solution for pressures in the distribution network. Although the differences are likely to be minor for computer models with many nodes, the simplest examples show differences of up to 25% in head loss between the two approaches. Terminology and concepts from structural engineering are useful in this comparison. The results are particularly significant to simplified models using independently derived values of pipe friction factor.

Keywords:

• Water distribution
• Darcy – Weisbach head loss
• Pipe network analysis