Substantiation of the parameters of the erosion jet underwater face

Abstract

Purpose: development of a mathematical model that describes the geometric parameters of the contact surface of an inclined turbulent flooded axisymmetric water erosion jet with an underwater face of incoherent soil. Methodology consists in developing a physical model of a turbulent flooded axisymmetric water erosion jet in contact with the underwater face of incoherent soil, a mathematical description of the expanding and changing direction of the jet stream, statistical processing of experimental data with the determination of numerical values of empirical coefficients. Findings. A physical model is developed for the contact of a turbulent flooded axisymmetric water erosion jet with an underwater face of incoherent soil. To develop a mathematical model, an assumption was made about the possibility of describing the process by an idealized calculation model obtained using experimental data and generalized by the methods of similarity theory and turbulent jets. As a result of evaluative processing of experimental data, empirical dependences are obtained to determine the geometric parameters necessary when constructing the contact surface of the erosion jet with eroded soil. The final formation of a mathematical model of the underwater zone of erosion of the suction dredge is carried out with the determination of the numerical values of the specified list of empirical coefficients. Testing of the developed method for calculating jet desintegrants took place during the development of the draft ejector dredger ZNS 630-90. Originality. The criterion empirical dependence was established for the first time to determine a sufficient number of geometrical parameters of the surface underwater face needed to adequately build the contact surface of the erosion jet with eroded soil. Practical value: The application of the developed mathematical model in the design of working member of the ejection dredger ZNS 630-90 allowed, while maintaining the given productivity, to reduce the equipment operating cost by 15%, to get the opportunity to mining soil with a grain size of up to 200 mm, to reduce the sand production cost by 12%.