Modeling unsteady and steady 1D hydrodynamics under different hydraulic conceptualizations: Model/Software development and case studies

Author(s)

Gomes Jr, Marcus N. ; Rapalo, Luis M. C. ; Oliveira, Paulo T. S. ; Giacomoni, Marcio H. ; do Lago, Cesar A. F. ; Mendiondo, Eduardo M.

• Document type: Journal article
• Source: ENVIRONMENTAL MODELLING & SOFTWARE; v. 167, p. 19-pg., 2023-06-14.

Abstract

The stage-discharge relationship is affected by hysteresis, especially in 1D river cross-sections with very mild slopes, and/or where backwater effects occur. To model these cases, hydraulic property (HP) estimations (e.g., hydraulic radius and conveyance) are usually required as closed-form functions of stage. However, these are typically unavailable for complex cross-sections with overbanks. For no sediment-laden flows, we created the HydroHP-1D tool to solve the 1D Saint Venant Equations aided by the cross-section HP stored in tables. It also simulates irregular and composite hydraulic cross-sections, allows hydrodynamic simulation using the single-channel method (SCM), and proposes the divided channel method (DCM) for steady and unsteady flow analysis. A wide range of applications in rivers such as the Little Washita River and the Upper Negro River, and comparisons with NOAA normal depth solver, HEC-RAS, and with an analytical solution shows a promising scenario of applying HydroHP-1D to estimate 1D steady and unsteady hydrodynamics. (AU)

• FAPESP's process: 22/08468-0 - Flash drought event evolution characteristics and the response mechanism to climate change considering the spatial correlation
• Grantee: Eduardo Mario Mendiondo
• Support Opportunities: Research Program on Global Climate Change - Regular Grants