The Influence of Wall Boundary Modeling on the Unphysical Frictional Loss Inside Horizontal Main Drain

Abstract

Sustainable provisions to reduce the water consumption pose new challenges for an optimal design in building drainage infrastructure. Hence, the accurate prediction of the water flow through building drainage system to assure its self-cleaning performance is an important issue associated with sanitary and construction fields. In order to investigate complex scenarios considering a variety of geometries and loading regimes, as well as the presence of solid wastes and sewages, numerical modeling and simulation are nowadays a promising approach. In the present work, a particle-based method is used to simulate transient free-surface flow inside a horizontal pipe. Since the modeling of the pipe geometry has significant influence on the numerical accuracy, an investigation on the unphysical frictional loss inside the pipe is carried out. Two wall boundary modeling are adopted: in the first one all domain is modeled by particles; in the second one the fluid domain is represented by particles whereas wall boundaries are modeled by triangular polygons. The results demonstrate that the polygon wall representation generates more accurate results than the original discrete wall particle model.