Theoretical basics of process of the dispersal system correction

Factors analysis, determining the stability of mineral dispersal systems during disintegration was done. A mathematical model of the process of formation of small particles of the mineral component of hydromineral mixture in the field of hydrodynamic influence is presented, initiated by cavitation. The identified basic dependency options allowed, experimental studies of the disintegration of mineral particles, using electron microscopy to control the process and assess its effectiveness. Developed ideas about structural and mechanical features of mineral hydro-mineral mixture taking into account thermodynamic potential, the preconditions are not only theoretical justification for the process, but also the development of applied research in the development of technologies and means of processing and enrichment minerals in environmentally friendly ways.

Study of the Interaction of a Packing Device with a Coal Seam at Interval Hydraulic Fracturing

The technological scheme of the interval hydrodynamic influence on the coal seam is considered. The design of a double-sided packer is presented, the results of laboratory tests to determine the axial movement of the seals during the interval fracturing are shown. The numerical scheme based on the Finite Element Method has been developed for calculating the stress-strain state of a rock in the vicinity of a well, loaded by internal pressure through packer seals. The pressure acting on the contacts between the seals and the well is calculated, the stress distribution in the geomaterial is investigated.

A numerical investigation of fluid flows induced by the oscillations of thin plates and evaluation of the associated hydrodynamic forces

The paper is devoted to the problem of harmonic oscillations of thin plates in a viscous incompressible fluid. The two-dimensional flows caused by the plate oscillations and their hydrodynamic influence on the plates are studied. The fluid motion is described by the non-stationary Navier–Stokes equations, which are solved numerically on the basis of the finite volume method. The simulation is carried out for plates with different thicknesses and shapes of edges in a wide range of control parameters of the oscillatory process: dimensionless frequency and amplitude of oscillations. For the first time in the framework of one model all two-dimensional flow regimes, which were found earlier in experimental studies, are described. Two new flow regimes emerging along the stability boundaries of symmetric flow regimes are localized. The map of flow regimes in the frequency–amplitude plane is constructed. The analysis of the hydrodynamic influence of flows on the plates allow us to establish new effects associated with the influence of the shape of the plates on the drag and inertia forces. Due to these effects, the values of hydrodynamic forces can differ by 90 % at the same parameters of the oscillation. The lower and upper estimates of hydrodynamic forces obtained in the work have a good agreement with the experimental data presented in the literature.

Improvement of the reliability and durability parameters of hydrotechnical structures under conditions of hydrodynamic influence of flows on structural elements

This article concerns the methodological issues of developing principles for increasing the reliability and durability parameters of equipment and auxiliary mechanisms of hydrotechnical structures. An analysis of the conditions ensuring an increase in the accuracy of engineering calculations of the viscosity of disperse systems is carried out. An analytical consideration of the effects of the particle shape on the calculation of the groundwater viscosity using the representations of particles of dispersed media as hydrodynamic dipoles is proposed. An equation for the viscosities of disperse systems is obtained with the determination of the shape factor of solid particles in a liquid. The comparison with the ratios for calculating the viscosity of ideal groundwater consisting of particles of a circular configuration indicates the possibility of reducing errors in calculating the coefficients of permeability of flow rates and pressures of filtration currents in underground horizons under the fluences of hydraulic structures. To improve the reliability of building structural elements operation of spillways without vacuum dams, a method of refined calculation of the dynamic effect of groundwater on the base of spillway dams and dams of the river bed is proposed.