Author(s): Cesar Augusto Vaz Santos; Cristina Maria Sena Fael; Juan Pedro Martin-Vide

Linked Author(s): Juan Pedro Martín Vide, Cristina Fael

Keywords: Complex pier; Hydrodynamics; Meander; Numerical study

Abstract: The present work resorts to ANSYS Fluent to analyse the Ebro River meander flow field and the effects caused by the large and complex pier of the Zaragoza Bridge Pavilion. The shape, size, and skewed position of the pier relative to the flow make the flow-structure interaction unique to this case. Initially, the surveyed bed topography is used in an inviscid model to provide qualitative insight into the flow field. Afterwards, a 1/62.5 scaled model is used for the turbulence modelling, considering a representative geometry of the meander. The RANS equations are solved using the Standard k − ε turbulence model. Comparisons are made with previous experimental work and field surveys. Results show that the core of high velocities along the bend is directed toward the outer bank. Under the right span of the bridge, a velocity increase of up to 50% is seen. On the left side, the velocity increase is less pronounced. Bed shear stress results show a twofold general increase in the vicinity of the pier and a five times increase on the right side. Secondary currents attain peak values of up to 12% of the streamwise velocity at the 115º section, then decrease toward the bend exit. The results indicate that the characteristics of the pier play an important role in the flow imbalance between the left and right bridge span. This behaviour contributes to exacerbating sediment accumulation on the left side and bed erosion on the right side, as seen on the field.

DOI: https://doi.org/10.3850/978-90-833476-1-5_iahr40wc-p1504-cd

Year: 2023