Experimental Study on Scour Due to Submerged Vertical Impinging Circular Jet

Abstract

AbstractIn this paper, the laboratory study of the scour has been carried out in cohesionless and cohesive sediments by submerged vertical circular impinging jet. The scour tests were performed using cohesionless sediments (sand and fine gravel) and cohesive sediments (38% clay, 52% silt, 10% fine sand). The characteristics of scour-like maximum static scour depth, temporal variation of scour depth, radius of scour, and dune height were obtained. An ANN model for predicting the scour holes dimensions from the hydraulic properties of the jet and the properties of the sediments was also developed. In case of cohesionless sediments, temporal variation of scour depth has been quantified by testing the functional relationships available in the literature and new working relations have been proposed for estimation of equilibrium scour time. Scour parameters have been analyzed using the data collected in the present study and that available in the literature. In case of cohesive sediments, maximum static scour depth has been analyzed with varying flow jet conditions. Working relations have been proposed to study the effect of various jet parameters and the maximum static scour depth and maximum volume of scour. The proposed equations have been validated by using the data collected in present study and the data reported in the literature. The data collected in present study has been analyzed in dimensional and non-dimensional forms to generate an ANN model to determine maximum scour depth, and their performance has been evaluated using coefficient of correlation.KeywordsStatic scour depthTemporal variationCoefficient of correlationANN model