Authors: Mohamed R. Torkomany, Enrica Viparelli, M. Hanif Chaudhry- University of South Carolina
Title: Pressurization of Stormwater Mains: Comparison between Simulation and Real-World Data
Abstract: Stormwater networks are essential to mitigate floods in urban and suburban areas. Recent research highlights how storm intensity and frequency are expected to increase in a warming climate with a consequent increase of flood risk. Stormwater mains are commonly designed to convey free-surface flows. However, during intense storms, the discharge may exceed the design conveyance capacity, and stormwater mains may become pressurized. Modeling the transition from free surface to pressurized flow remains challenging in presence of air above the free surface in the main headspace. An innovative model of stormwater flow simulation that explicitly accounts for air compressibility during pressurization is presented. Free-surface flow is numerically modeled using the explicit finite difference Lax-Diffusive scheme. The Preissmann slot handles water pressurization, and the model is integrated with an airflow module that allows modeling of air compressibility as a compressible, pseudo-compressible, and incompressible fluid. Preliminary results show satisfactory agreement with results from the literature, and the model will be used to investigate how air vent size, location, and number impact stormwater flow.