Socavación producida por chorros verticales circulares y rectangulares sumergidos

Abstract

In this paper, an experimental research on the local scour phenomenon on sand beds, produced by the impingement of submerged rectangular and circular vertical water jets, is presented. Experiments were carried out in a tank of circular cross section of 0.75 m diameter and height of 0.84 m, with a suitable constant-head arrangement. For the case of circular vertical jets, the mean diameter of the sand particles used as bed material was d50 = 3.1 mm. The circular jet nozzle diameters were 6.5, 12.9 and 16 mm. The discharge supplied to the model varied between 1.67x10-4 and 1.974x10-3 m3/s. In total, 60 experiments were performed. An additional study of rectangular vertical jets was performed. Experiments were carried out varying the rectangular cross section of the nozzle. These had an aspect relation of 2, 4 and 6. Two different sizes of sand were used as bed material. The first granular material was fine sand with d50 = 0.055 cm and the second coarse sand with d50 = 0.14 cm. The discharge varied between 3.8x10-4 and 1.30x10-3 m3/s. For rectangular vertical jets, 90 experiments were performed. From the experimental investigation, empirical relationships that allow to predict the characteristic lengths of the final steady state scour hole are developed.