Pressure extrema in energy-dissipating structure using block maxima: case study

Abstract

Knowledge of hydrodynamic processes is essential for engineers who assess the stability of energy dissipation structures undergoing extreme pressure fluctuations caused by turbulence during high discharge. Methods are in particular required to evaluate the frequencies of occurrence of extreme pressures. This work explores the use of the generalized extreme value (GEV) distribution to represent frequencies of instantaneous pressures recorded in a structure designed for energy dissipation by a hydraulic jump in a hydroelectric power station at Porto Colombia in central Brazil. The goodness of fit of the GEV distribution was evaluated using probability plots and the Kolmogorov–Smirnov test. The results indicate that it is appropriate for studying the maximum and minimum pressures for a range of discharges corresponding to Froude numbers between 3.88 and 6.42.

Keywords:

• Block maxima
• hydraulic jump
• pressure extrema
• prototype measurement
• stilling basin

Acknowledgement

The authors are grateful to Furnas Centrais Elétricas SA for having provided the pressure data of the HPS at Porto Colombia.