Evaluation of Pressure Fluctuation in Hydraulic Jump by Dissociation of Hydraulic Forces

ABSTRACT

Hydraulic jump is a phenomenon largely used to dissipate energy downstream of hydraulic structures due to their biphasic and macroturbulent characteristics, associated with intense pressure, velocity and level fluctuations. These sudden pressure variations can cause damage to stilling basins, such as: cavitation erosion and superelevation of the floor slabs. Therefore, it is essential to know the behavior of pressure fluctuations along the hydraulic jump to look for safe and economic solutions. This work aims to identify and predict the characteristics of pressure fluctuations, at the bottom of the stilling basin, considering the hydraulic jump as a sum of hydraulic effects individually identified with distinct flow conditions. To do so, the pressure distribution was monitored and analyzed on average terms, and its fluctuations and extreme values along the solid outlines. The approach proved effective for the compression of the phenomena allowing the estimation of values for different outline conditions.

Keywords:
Hydraulic structures; Pressure fluctuation; Energy dissipators