Exploring Two-Phase Flow Dynamics: Experimental Investigations and Computational Modeling in Smooth and Stepped Chutes | Chapter 6 | Theory and Applications of Engineering Research Vol. 2

 Cavitation damage to hardened structures is coarse in dam spillways. Cavitation can lead to cracks on the actual surface which further increases the risk of damage to hardened by means of sulfate attack, freeze-unfreeze, alkali-silica response, and others. Cavitation damage happens on concrete surfaces when discontinuities or irregularities are met in the path of speedy water flow. Stepped spillways are acceptable, economic alternatives for high-volume depository dams that require meaningful energy amusement, for structural reworking to roller-compressed concrete dams, and to advance spontaneous flow aeration. In this place study, numerical analysis of the hydraulic traits for the skimming flow government of over the stepped chute of the Zirdan Dam is carried out. A corresponding between the flow traits for stepped and smooth spillways is given. By preparing numerical models utilizing the k-ε RNG turbulence model and the multiphase combination method, a hydraulic reasoning of the flow was completed. To validate the performance of the mathematical model, field data was composed and used for confirmation. The results show that the presence of steps along the chute cause a significant decline in the length of the perimeter layer and faster aeration happens. In a stepped chute, the cavitation index is higher than the fault-finding limit along the whole length of the spillway. So, the risk of cavitation and destruction is insignificant. On the other hand, accompanying a smooth spillway, the likelihood of cavitation may happen. This negative effect (negative pressures) occurs 56 m from the ridge of the spillway on the coming after side. For the design discharge, the difference in energy wantonness for the stepped and smooth chute is 47%.

Author(s) Details:

Farzin Salmasi,
Department of Water Engineering, Faculty of Agriculture, University of Tabriz, Tabriz, Iran.

John Abraham,
School of Engineering, University of St. Thomas, Minnesota, USA.

Please see the link here: https://stm.bookpi.org/TAER-V2/article/view/12949