Author(s): Ling Zhou Iahr Member; Deyou Liu; Lin Xia
Linked Author(s): Ling Zhou
Keywords: Water pipeline system; Transient flow; Entrapped air pocket; Air-water interface; Tail water; Pressure surge
Abstract: The air-water transient flow in rapidly filling horizontal pipe is investigated analytically. Based on the elastic water theory, a partially full model was developed by considering the initial water depth and the filling column variation. The comparisons of pressure surge between the results of full model (which assumes the air pocket occupies the entire cross section and neglects the effect of tail water), partially full model and experiments also were conducted. Based on a large number of experimental data, the partially full model shows fairly good overall agreement with experiments in the peak air pressure while the full model breaks down for systems with the deep tail water and long air pocket. Furthermore, the experimental observation shows that tail water nearly keeps stable during the first air compression, which demonstrates the assumption of stable tail water in the proposed model could be acceptable for the fast transients. Consequently, the partially full model can effectively simulate the transient flow in a filling full or partially full pipe.
Year: 2013