ABSTRACT
ABSTRACT: A review of recent developments in numerical modeling of unsteady dispersion in water distribution pipes is presented. The hydrodynamic process is described by the twodimensional advection-dispersion-reaction equation. Although this equation can be numerically solved, such a solution is impractical for modeling the dispersion in networks, so that the equivalent one dimensional equation is used. A numerical solution for pipe networks is then proposed, based on numerically computed Green functions. Thus, the large system of equations that represents the discretized network is decomposed exactly in three easy-to-solve tridiagonal systems for each pipe, and one low order system for the concentration at the pipe junctions. In each pipe the solution is represented by the superposition of a homogeneous (zero boundary conditions) solution, and two numerically obtained Green function solutions. Henceforth, continuity balance relations are used to construct a system of linear equations for the unknown quantities at the network nodes. Comments on the applicability of the proposed model in laminar turbulent flow pipes and are presented.
