Author(s)

Theodore V. Hromadka II¹, Prasada Rao²

¹Department of Engineering-Mathematics, United States Military Academy, West Point, NY, USA.
²Department of Civil and Environmental Engineering, California State University, Fullerton, CA, USA.

In this work, for flow with a hydraulic jump, the predictive capabilities of popular hydraulic models (HEC-RAS and WSPG) are validated with the published results from the three dimensional Computational Fluid Dynamics (CFD) model (OpenFOAM). The analysis is performed for flows with a Froude number of 6.125 and Reynolds number of 3.54 × 10⁵. While the hydraulic models solve the one-dimensional energy equation, in the CFD model solution of the three dimensional Reynolds averaged Navier-Stokes (RANS) equations, with a turbulence model, is used. As the results indicate, although the hydraulic models can satisfactorily predict the location of the steady-state jump, the length of the hydraulic jump (i.e. distance from the toe of the jump to a location in tail water zone) and other jump characteristics are better simulated by the CFD model. The solution from hydraulic models is sensitive to the channel bottom roughness value.

OpenFOAM, HEC-RAS, WSPG, Rapidly Varying Flows

II, T. and Rao, P. (2019) Examination of Computational Precision versus Modeling Complexity for Open Channel Flow with Hydraulic Jump. Journal of Water Resource and Protection, 11, 1233-1244. doi: 10.4236/jwarp.2019.1110071.