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At the oil production wells of Gazpromneft Vostok LLC, with the problem of scale formation, there was made an assessment of the possibility of using an encapsulated scale inhibitor. According to the test results, it’s found that the reagent provides effective protection of production wells from salt deposits. There are noted such a positive aspects of this inhibitory protection technology as the absence of corrosive effects on downhole equipment, the possibility of quick organization of well protection, not using metering equipment, independence from the infrastructure and the convenience of loading capsules during workover. A comparative analysis with the classical inhibitor protection with liquid scale inhibitors has been carried out. It is shown that with a water flow rate of up to 38 m3 / day, the use of encapsulated reagents is more cost effective. The limitations of the application of the technology are noted – the difficulty in carrying out additional loading of the reagent into the well without lifting the downhole equipment, application in horizontal and directional wells.

Car engine cooling is actual problem today. The work considers the gas flow in aluminium open cell foam material with two different values of the porosity of the medium 0.9 and 0.7. Models of porous media with an ordered and random structure have been created; in both cases, the porous medium is constructed by a set of intersecting spheres. Numerical modelling of gas flow and heat transfer in a porous medium is carried out using the control volume method in the ANSYS Fluent software package (v. 19.0). The results of the calculation of the pressure drop correlate well with the results of calculations obtained by the semi-empirical dependence. Given the best mixing of the flow, convective heat transfer is more intense in the model of a porous medium with a random arrangement of cells. The highest porosity of medium 0.9 provides the lowest pressure drop and increases the value of heat transfer. It has been shown that in a porous medium of any geometry, the Nusselt number increases with increasing Reynolds number. In this case, open cell foam with a random arrangement of pores in space and a maximum porosity of the medium is preferred for use as a heat exchanger in transport.

The article presents a numerical simulation of the gas flow in pre-filter models. It was proposed nine models of pre-filters with grating sizes of 1mm, 1.5mm and 2mm, with a change in the number of plates. Pre-filters were compared in terms of particle deposition efficiency, pressure drop and filter quality parameter.

In this work, we made a comparative calculation of a granular filter with different shapes of the granules. We created granular filter models with solid and porous granules. The diameter of the granules was 5 mm, and the porosity was ε = 0,8. A comparison was made on the deposition efficiency, pressure drop, porosity, and filter quality parameter. We have found that for a filter with porous granules, the particle deposition efficiency is slightly lower than for a filter with solid granules. However, the pressure drop is an order of magnitude higher for a filter with solid granules, which ensures the maximum value of the filter quality.

A mathematical model of the acetylene hydrogenation reaction is constructed. Numerical modeling and experimental studies of the hydrogenation of acetylene in a reactor with a catalyst based on open cell foam material have been carried out. The results of numerical modeling and experimental studies are in good agreement. The calculation results show that with increasing temperature in the reactor, the mass content of acetylene decreases.

In this work, we estimate the contribution of the prefilter to the operation of the filter-prefilter system and propose two models of prefilters with curved plates. Numerical calculations of the aerosol flow in various combinations of filters and prefilters are carried out. We calculate the particle deposition efficiency of different filter models. The prefilter in the case of five and ten plates increases the limit of deposition efficiency for open cell foam material. A prefilter with five curved plates with parameters l=0.33 mm and h=4 mm is more preferably in comparison with ten plates with parameters l=0.33 mm and h=2 mm.

In this work, we performed experimental and numerical simulation of gas flow in the model of the open cell foam filter. We investigated the relationship between the porosity of the medium ɛ, and the parameter Po characterizing the number of pores per inch. We obtain a porous medium from the inverse matrix of the computational model made on a 3D printer. The calculation results of the pressure drop depending on the average filtration rate correlate well with the experimental data. Particle trajectories make it possible to determine the particle deposition efficiency in a porous layer for three values of the porosity of the medium ɛ = 0.6, ɛ = 0.7 and ɛ = 0.8 . The deposition efficiency in the case of porosity ɛ = 0.8 correlate well with the data obtained by the semi-empirical formula of the authors of [1], however, for the other two values of the porous medium, the efficiency curves differ significantly, so the dependence was obtained for a material with high porosity. We define the filter quality parameter by the ratio of the particle deposition efficiency to the pressure drop value in the porous layer.

The research work presents the results of mathematical modeling of the ethylbenzene dehydrogenation process to styrene in a fixed catalyst bed. Calculations for the different length granule packaging are carried out. Calculated values of the reaction product yield (styrene) are in a wide range of gas velocities. There are significant differences in the yield of the product at high gas velocities for catalyst granules of different shapes. Of the considered catalyst granules forms, we got the best yield efficiency by the use of granules, which provide maximum surface area and porosity in the fixed bed catalyst.

Numerical simulation of the aerosol flow in a tube with a porous insert (which is a filter model) of the fixed porosity of ε = 0.6 and with different cell diameters was performed. The method of constructing the geometry of the open cell foam material is described. Images of the trajectories of inertia and low-inertia particles inside the porous medium are presented. Figures of changes in the efficiency of particle deposition are presented for a typical filter pore diameter of d c = 4 mm, d c = 5 mm and d c = 6 mm for different thicknesses of the porous insert. It is revealed that the effective thickness of the porous insert, with which the value of the deposition efficiency of media with different pore diameters does not change, is 4 cm. Recommendations are given on the choice of filtering open cell foam materials with specified parameters.

The procedure of measuring the intraocular pressure by an optical analyzer is numerically simulated. The cornea and the sclera are considered as axisymmetrically deformable shells of revolution with fixed boundaries; the space between these shells is filled with incompressible fluid. Nonlinear shell theory is used to describe the stressed and strained state of the cornea and sclera. The optical system is calculated from the viewpoint of the geometrical optics. Dependences between the pressure in the air jet and the area of the surface reflecting the light into a photodetector are obtained. The shapes of the regions on the cornea surface are found from which the reflected light falls on the photodetector. First, the light is reflected from the center of the cornea, but then, as the cornea deforms, the light is reflected from its periphery. The numerical results make it possible to better interpret the measurement data.

A geometrical model of the open cell foam was created as an ordered set of intersecting spheres. The proposed model closely describes a real porous cellular structure. The hydrodynamics flow was calculated on the basis of a simple model in the ANSYS Fluent software package. A pressure drop was determined, the value of which was compared with the experimental data of other authors. As a result of the conducted studies, we found that a porous structure with smoothed faces provides the smallest pressure drop with the same porosity of the package. Analysis of the calculated data demonstrated that the approximation of an elementary porous cell substantially distorts the flow field. This is undesirable in detailed modeling of the open cell foam.