Hydraulic Modeling of Irregular Open Channels and Evaluation of the Accuracy of the Finite Element Method in Predicting Free-Surface Flow Levels

Farhad Aslani shotorbani¹

1) M.Sc. in Mechatronics Engineering, Tabriz Metropolitan Municipality, Iran Email:

IOI Code : AAHE-ABAZGZ
Publication : National Conference on Civil Engineering, Design and Construction Technologies, Energy, Materials and Advanced Machinery(icaeu.ir)
Abstract :
    Accurate modeling of water flow in open channels with irregular cross-sections plays a crucial role in analyzing hydraulic behavior, optimal design, and the management of water conveyance systems. The geometric complexity of such channels limits the accuracy and efficiency of classical analytical methods; therefore, the use of advanced numerical techniques becomes essential. In this study, numerical modeling of the free-surface flow profile in open channels with irregular cross-sections is carried out using the finite element method. The governing flow equations, including the continuity and momentum equations, are solved assuming incompressible flow and applying appropriate boundary conditions. The computational domain is discretized using a mesh conforming to the actual geometry of the channel cross-section, and the effects of variations in cross-sectional shape, longitudinal slope, and bed roughness on the free-surface flow profile are investigated. The numerical simulation results indicate that the finite element method has a high capability in predicting flow depth distribution and free-surface variations in channels with irregular cross-sections, showing good agreement with empirical relations and reference hydraulic data. Furthermore, it is observed that geometric irregularities of the cross-section have a significant influence on flow patterns and local free-surface variations, which should be carefully considered in engineering designs. Finally, the results of this research demonstrate that the finite element method can be effectively used as an accurate and efficient tool for the hydraulic analysis of irregular open channels, particularly in water engineering projects and water resources management.

Keywords : open channel flow free surface profile finite element method irregular cross sections numerical modeling