Authors: Lylie Wilkie, Mohamed Torkomany, Enrica Viparelli, M. Hanif Chaudhry – University of South Carolina
Title: Air flow modeling in Stormwater Collection Networks. Comparison of modeling approaches
Abstract: Hydraulic modeling of stormwater mains is complex due to presence of free-surface and pressurized flows in time and/or space. In general, the analysis of air flow accounts for pressurization and depressurization of air above the water surface, inflow and outflow. Understanding and accurately modeling air flow in stormwater mains is critical to reliably predict flow properties and thus support stormwater and emergency managers. This work summarizes results of numerical simulations designed to perform a comparative analysis of air flow modeling approaches in stormwater mains. The analysis is performed using CHANNEL, a 1-D unsteady-flow model that explicitly accounts for air flow in mains using different approaches for air compressibility. In particular, air is considered either incompressible, pseudo-compressible, or compressible. The comparison between model results is done in terms of computational efficiency and accuracy and provides guidance for the selection of the most suitable approach for different time and accuracy constraints.