INFLUENCE OF OPERATION MODE OF SPILLWAY DAM GATES ON TAILRACE EROSION
Subject of the research is to determine the operation modes of the spillway dam gates of the Cheboksary hydroplant, which provide the optimal flow velocity in the tailrace in the context of minimization of erosion behind the end fixing of the apron. Parameters of the existing local erosion behind the apron and the causes of its formation are considered. Experimental study of possible riverbed deformations at various openings of the gates is conducted in the hydraulic flume on the model of the spillway dam with the erodible area on a scale of 1:100. Scale of similarity of the bed erosion in the hydrosystem tailrace is obtained, based on the method of dimensional analysis. When modeling, the full-scale soil is replaced by model one, which has equivalent mechanical strength. Preliminary analysis of the object of study is performed and the plan of experiments is drawn up. The most dangerous operation mode of the gates is established. Means of protection against erosion in the tailrace are suggested.