Author(s): Huaicheng Fan; Qingzhi Hou; Xuliang Yang

Linked Author(s): Qingzhi Hou

Keywords: Elastic model; Entrapped air pocket; Smoothed particle hydrodynamics; Unsteady friction model

Abstract: Urban flooding has caught lots of attentions around the world. It has been verified that the water flow regime transition and impact pressure can be affected by entrapped air pocket in urban drainage pipeline system. Traditional rigid column model cannot capture the pressure oscillation due to water hammer effect for neglecting water compressibility. As a particle method, smoothed particle hydrodynamics (SPH) provides an effective way to introduce the water compressibility into simulation. In this paper, an elastic model with unsteady friction is developed to simulate the transient flow in pipelines with entrapped air pocket at the dead end. In this model, the steady Darcy-Weisbach friction model is replaced by the Brunone unsteady friction model in classical water hammer equation. Two different cases are studied to verify the proposed model. The results show that the SPH-based elastic model can effectively predict the pressure oscillation in the system due to compression of entrapped air pocket. The unsteady friction model has no significant effect on the entrapped air in pipeline with a dead end.

DOI: https://doi.org/10.3850/iahr-hic2483430201-103

Year: 2024