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Stress-strain states (SSS) of vertical steel tanks are described along with a method for calculating their strength using CAD technology that takes into account such factors as uneven settlement of the base, displacement of the tank walls, and the effect of the size of the annular plate.

Characteristics of gas flow distribution in the active section of dry type electrostatic precipitators (electrofilters) are considered. Disadvantages of traditional electric filter designs are indicated. Results obtained in the course of modeling gas flows in different electrofilter sections are presented. Recommendations for uniform gas flow distribution in the active section of the electric filter are proposed.

To upgrade the design of scraper-type crystallizers used in the production of engine oils, a design of the crystallizer shaft with scrapers preventing shaft jamming is proposed. This is ensured by the installation of scrapers on special springs that provide the necessary pressing force of the scraper and the possibility of angular deflection in case of increased loads.

The article discusses the application of laser scanning technology to assess the volume and mass of bulk materials, as well as the construction of the 3D models on the basis of data obtained. The developed device has practical application in construction. Bulk raw materials is a significant part of the costs of the enterprises and it is necessary to control its volume for the efficient distribution. The required accuracy of volume determination depends on the cost per unit volume of bulk material and can vary widely. The problem with measurement is that the volume/mass of cargo is often falsified by freight forwarders and shipping companies. In order to solve this problem it is necessary to develop a set of methods and special devices for rapid assessment of the volume of bulk materials carried in the car body before its unloading. It was found that customers of bulk materials such as gravel, crushed stone, sand lose at least 16% of the cargo on average. This value is essential, since the required accuracy of determining the volume depends on the cost per unit volume of bulk material and can vary widely. The proposed method will help to make it 85% lower, i.e. down to 2.2%

The article presents a mathematical description of the formation process of cavitation bubbles in a new design of axial control valve fitted with a rotary locking device. The differential distribution function of the number of cavitation bubbles by size is obtained for use in calculating the main valve parameters.

The process of mixing of bulk materials in a newly developed continuous drum-blade mixer is investigated. The presence in cross-sections of the material of two zones of characteristic behavior of the material, an active mixing zone and a transporting zone, is established. (It is assumed that the parameters of these zones do not vary along the length of the mixer, but that the homogeneity of the mixture varies.) The mixing process is described by means of an isotropic approximation of the Fokker–Planck kinetic equation. The structure of the macrodiffusion coefficient is determined on the basis of well-known representations of the statistical theory of interaction of dispersed media. In accordance with a model, the results of the calculation exhibit satisfactory convergence with the results of an experiment.

When describing the mechanics of the behavior of bulk materials during their mixing, a theoretical basis for the design of the specified equipment is formed. In recent years, the most well-known methods of modeling this process include the stochastic approach, in the framework of which models of the following types are actively developing: cell, managerial, with time series, energy, etc. Moreover, as a rule, predicting the quality of the finished mixture according to the selected criterion is achieved by using numerical calculation methods based on the generated cyber system. Of particular interest is the use of the energy method from the statistical mechanics of nonequilibrium processes due to the possibility of obtaining analytical simulation results. The paper describes the motion models of bulk components in rarefied flows, which are built on the basis of the energy method and take into account the main characteristics of the studied mixing process.

The purpose of the work is to develop an analytical method for calculating the effective ranges of structural parameters of the throttle part of the axial valve with the external location of the locking shell based on the proposed stochastic models of bubble formation at the initial stage of hydrodynamic cavitation. In contrast to the well-known engineering methods for choosing the conditional bore diameter for the designed control device constructed using the Pi-Buckingham theorem, this calculation method relies not only on gyrodynamic similarity criteria, but also on functional dependences for the laws of distribution of cavitation bubbles according to various characteristics (specific size bubbles, the degree of opening of the node “separator-external locking shell”). This takes into account a wide range of design and operating parameters, including the required valve capacity, as well as the physical and mechanical characteristics of the working medium. A block diagram of the calculation of the node “separator-external locking shell” for the specified axial valve is proposed. The influence of a set of design parameters for the “separator-external locking shell” assembly from the rational ranges of their variation obtained using the proposed analytical calculation algorithm on the size of cavitation bubbles is investigated. It has been established that when using the latest results in comparison with the values of parameters from irrational ranges of change, there is a tendency to reduce the ensemble average value of the diameter of the cavitation bubble by 1.95 times, when switching to a mode from 20% of the degree of separation of the separator to 80% of the opening of the throttle holes, the nominal valve capacity increases by 10.7 times. The results obtained illustrate the possibility of preventing an increase in the intensity of formation of cavities in the flow part of the control device already at the initial stage of the occurrence of cavitation.

The purpose of this study is a stochastic description of the distribution of solid dispersed components, including those from secondary raw materials, according to the characteristic angle of scattering ϴij when receiving a construction mixture at the first stage of operation of the rotary apparatus. Two stages of the formation of rarefied flows are assumed: when scattering particles of components by elastic blades of a rotating drum and when interacting with the baffle surface. Modeling method this is energy method of Klimontovich Yu.L. The analysis of the efficiency of the first stage (rotary mixing) is carried out based on the obtained distribution functions of the number of particles of bulk components over the scattering angle, taking into account their physical and mechanical properties and a variety of design and operating parameters of the apparatus. The bulk of the particles of the mixed components are scattered at the initial angles of rotation of the mixing drum, when the deformation of the elastic blades is most significant. This is accompanied by the characteristic first bursts of the obtained distribution curves (ϴij< 0.1 rad) for the number of particles of the tested bulk materials at the given ranges of parameters.

The purpose of this work is to analyze the coefficient of hydraulic resistance in the separator of a direct-flow control valve with a rotary lock according to the approximation of the superposition of pressure losses in elementary local resistances. In contrast to the known methods of constructing simulation models, the proposed analytical method of calculation is based on a qualitative assessment of the specified coefficient in the implementation of throttling of fluid flows in the “separator-rotary lock” unit, depending on the design and operating parameters of the process. It was found that, within the selected range of variation of the separator parameters, an increase in the valve opening degree from 20% to 50% leads to a decrease in the hydraulic resistance coefficient by 19.6 times, and an increase in this degree from 20% to 100% is associated with a 42.4-fold decrease in the studied characteristic. This circumstance justifies the effectiveness of the proposed method for throttling the flows of the working medium. The results obtained are used to study the influence of the main design parameters of the “separator-butterfly valve” unit on the flow capacity of the control valve and are relevant for stochastic modeling of the hydrodynamic cavitation process.

The object of research is the process of mixing bulk materials in a gravity-type apparatus with additional mixing elements in the form of brushes and bump-stop. The problem of obtaining bulk mixtures with a ratio of components of 1:10 or more is relevant, for example, for the construction industry in the preparation of preliminary compositions for the production of glass or mixtures of mineral materials in the secondary processing of asphalt concrete. Within the framework of the stochastic approach with the analysis of the energy states of the system, a method has been developed for calculating the volumetric flow rate of bulk materials for each of the three stages of mixing in the indicated gravitational apparatus in an analytical form depending on the input parameters of the authors’ models for the formation of rarefied streams by various types of mixing elements. The analysis of the dependence of the volumetric flow rate of bulk components during operation of the specified apparatus at each mixing stage depends on the main process parameters. The results obtained are in satisfactory agreement with experimental data. The expression for the volumetric flow rate of bulk components can be used in the formation of an engineering methodology for calculating the parameters of the gravitational-type apparatus with additional mixing elements.

The purpose of this work is to analyze the distribution of bulk materials according to the characteristic parameters of the mixing process at the second stage of processing in a rotary apparatus. The design of the rotary device has a wide range, including for the needs of agriculture, for example, when forming mixtures of mineral fertilizers and multifunctional pyrethroid drugs. At this mixing stage, impact interaction with the bump surface of rarefied flows of bulk components occurs, obtained by scattering the rotating drum by elastic blades at the previous stage of the technological chain. The obtained dependencies between the characteristic angle of dispersion of bulk materials by the specified mixing drum (at the first stage) and the angle of reflection of the corresponding flows from the baffle surface (at the second stage) are used in the stochastic analysis of impact mixing. Modeling of the differential functions of the distribution of the number of particles of mixed bulk components by the angle of reflection from the baffle surface is carried out taking into account the physical and mechanical characteristics of the working materials, design parameters, and operating parameters of the rotary apparatus. The calculation results made it possible to reveal the effective ranges of variation of the characteristic parameters for the shock mixing of bulk materials in a rotary apparatus.

The object of research is the process of formation of vapor-gas bubbles at an early stage of hydrodynamic cavitation during throttling of the liquid in the axial valve separator. Designing a separator under conditions of decreasing bubble formation intensity is an urgent problem. Based on the energy approach, a stochastic model of the formation of an energetically closed system of bubbles in the separator according to the Gibbs ensemble is proposed. Analytical dependences are obtained for the density function and the bubble geometric characteristics averaged over the ensemble, depending on the design parameters, operating parameters, and physic-mechanical properties of the working medium, including the ratio of the gas and vapor contents in the inner cavity of the bubble. The expressions for the indicated distribution function over the size of the bubbles and for the ensemble-averaged characteristics of the system of bubbles formed (diameter and surface area) can be used in the formation of an engineering methodology for calculating control equipment.

On the basis of the model of the process of movement and compaction of disperse mixtures in the roll gap after medium backup with a horizontal screw feeder the method of determination of integral characteristics of roller machine depending on the porosity of the working medium, its rheological properties and the structural and regime parameters of the designed device was proposed.