Simulation ofthe flow chart ofthe skyjump and the dissipation pond ofthe Poechos Reservoir using the Ansys CFX program

Reyes Salazar J.; Brayand M. · Proceedings of the IAHR World Congress (2022) · DOI: 10.3850/iahr-39wc2521716x20221716

Resumen

The Poechos reservoir is one ofthe largest hydraulic works in Peru, it regulates the great avenues ofthe Chira River and supplies water to the Chira and Piura valleys. It has a spillway with three radial gates with a maximum evacuation of 5,400 m3/s, through a ski jump to a dissipation pond. However, the flow hits a hill located in front, preventing a direct outlet to the Chira riverbed, located to the right. This recirculates the flow in the dissipation pond and consequently generates erosion in the vicinity of the dam foundation, where a protective rockfill has now been placed. The main objective is to model the phenomena that occur in the dissipation pond and study the erosion in the vicinity of the dam foundations, to propose an alternative solution. The model has been elaborated on a 1/100 scale in the Ansys CFX program, covering the ski jump and the dissipation pool, therefore, the results obtained have been converted by using the Froude similarity. These show average velocities of 1.6 m/s and maximum velocities of up to 6 m/s, located in the vicinity of the dam foundation. The existence of erosion is confirmed, since the surface of the dissipation pond is made up of soils such as sandy gravel, silty sand and silt, these materials do not resist velocities greater than 0.5 m/s.

Instituciones: Universidad de Piura