608 - An Equivalent Orifice for Short Conduits in SWMM

Wednesday, May 22, 2024

5:30 PM – 5:45 PM CT

Room: Ballroom B

Co-Author(s)

Ben R. Hodges

Professor
University of Texas at Austin
Abdulmuttalib Lokhandwala

Ph.D. Student
The University of Texas at Austin
Sazzad Sharior

Graduate Student
University of Texas at Austin

Author (not presenting)(s)

AA

Adithya Pazhoor Abraham

Model time steps in the US EPA Storm Water Management Model (SWMM) are typically controlled by the shortest links in the network. This problem is exacerbated in the finite-volume SWMM5+ hydraulic solver due to the need to provide a minimum number of computational elements in each link. The typical approach to this problem is to artificially lengthen short elements, which addresses the problem but at the cost of model fidelity. Herein, we propose an equivalent orifice algorithm that replaces a short conduit link with an orifice whose behavior mimics the expected head loss using the energy equation. This algorithm eliminates the need to artificially lengthen links and does not significantly impact the model results.