Experimental study of scour downstream of a stilling basin under inclined wall jets

This study presents a detailed experimental investigation of scour development downstream of a stilling basin under inclined wall jets. Experiments were conducted in a laboratory flume under free and submerged jet conditions for varying discharges, sluice openings, and tailwater depths. Flow characteristics, velocity profiles, and scour evolution were analysed using Acoustic Doppler Velocimeter measurements and bed profiling. The results show that increasing submergence causes jet diffusion over the stilling basin which significantly reduces the momentum of the jet and scour depth downstream of the stilling basin. Self-similar scour profiles were identified, and regression-based equations were developed for the prediction of equilibrium scour profiles. In addition, multilinear and nonlinear regression equations were proposed for the computation of maximum scour depth. The proposed equations perform better than the existing equations.