7 research outputs found

    Study of fluid layer gravity motion over vertical surface

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    This paper presents the results of studying the motion of a liquid layer along the walls of a vertically installed pipe under the action of gravity. Two-dimensional boundary layer is formed by the fluid motion relative to the hard wall on surfaces of structures (pipes, turbines, heat-and-mass transfer equipment, aircrafts, ships, etc.), which are of positive interest in engineering practice. Further upgrading of the above-mentioned structures is possible only by increasing accuracy of momentum in the boundary layer, heat and mass transfer rates calculation. It is confirmed that in the boundary layer transfer phenomena intensity (perpendicular to the wall) is due to the fluid particles velocity distribution regularities in the cross-section of the layer. Fluid velocity distribution regularities in turn are conditioned by Reynolds number according to current notions. The principal method of quantitative analysis of turbulent flow in a boundary layer suggested by Reynolds continues to be the velocity and pressure fluctuations averaging method for some timespan. The suggested model of fluid movement enables to prognosticate conditions under which in cross-sections of the boundary layer reshaping of velocity profile takes place, to carry out analytic calculation of such hydrodynamic characteristics as mean velocity of motion, layer thickness and shearing stresses acting on the wall. The difference between the suggested methods developed for calculation of flow parameters from the well-known ones is in that that calculations are made based on an integrated approach regardless of such conceptual definitions as laminar and turbulent regimes widely used in modern hydrodynamics. Obtained results and design formulas known in the literature have been compared. It has been found that the thickness of the sliding layer, determine by the proposed calculation formula, 1.17 times smaller than that determined by the currently used formul

    Electrosaving system of stable management of crop cultivation in highlands and lowlands

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    Agriculture is one of the strategic spheres of the economy in highland and lowland regions, the main impact of its development by farmers isthe management of stable regimes of cultivating crops. Nowadays in Armenia and Artsakh, agriculture develops mainly due to enlarging mostly agricultural crop lands. As a means of solving the main task, one method of calculating the parameters of irrigation regimes is suggested in the case of drip and sprinkle irrigation

    The application of anti-filtering polymer mass to solve the water storage problem in highland regions

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    Using additives with water absorbing characteristics enables us to increase the amount of water in natural basins and significantly decrease the amount of water for agricultural usage. Despite various additives already existing, they are yet to be commonly used due to high cost price, complex technology, toxic impact and instability in biological and atmospheric conditions. However, the «Natlen» composite, which is anaturally based additive, is ecologically safe. It has a long shelf life, is cheap and provides high antifiltering rates. The composite is eruptive with dispersity of any type and is jelly when boosted. In an antifiltering layer it never cracks under static and dynamic influences. It has no seam and is resistant to aggressive liquids. It is ecologically safe. «Natlen» composite is recommended for building water basins in pastures, where it can particularly be used to satisfy the demand for drinking water for cattle

    Study of Fluid Layer Gravity Motion Over Vertical Surface

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    This paper presents the results of studying the motion of a liquid layer along the walls of a vertically installed pipe under the action of gravity. Two-dimensional boundary layer is formed by the fluid motion relative to the hard wall on surfaces of structures (pipes, turbines, heat-and-mass transfer equipment, aircrafts, ships, etc.), which are of positive interest in engineering practice. Further upgrading of the above-mentioned structures is possible only by increasing accuracy of momentum in the boundary layer, heat and mass transfer rates calculation. It is confirmed that in the boundary layer transfer phenomena intensity (perpendicular to the wall) is due to the fluid particles velocity distribution regularities in the cross-section of the layer. Fluid velocity distribution regularities in turn are conditioned by Reynolds number according to current notions. The principal method of quantitative analysis of turbulent flow in a boundary layer suggested by Reynolds continues to be the velocity and pressure fluctuations averaging method for some timespan. The suggested model of fluid movement enables to prognosticate conditions under which in cross-sections of the boundary layer reshaping of velocity profile takes place, to carry out analytic calculation of such hydrodynamic characteristics as mean velocity of motion, layer thickness and shearing stresses acting on the wall. The difference between the suggested methods developed for calculation of flow parameters from the well-known ones is in that that calculations are made based on an integrated approach regardless of such conceptual definitions as laminar and turbulent regimes widely used in modern hydrodynamics. Obtained results and design formulas known in the literature have been compared. It has been found that the thickness of the sliding layer, determine by the proposed calculation formula, 1.17 times smaller than that determined by the currently used formul

    Experimental research on the filtration properties of an untamped mixture with "PMM" polymer mineral material

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    Polymermineral material "PMM" has multiple cycles of swelling and drying. It does not decompose under soil, biological and atmospheric influences and is environmentally safe. By adding the proportion of up to 30 g/kg of PMM additive to soil and tamping, we get a waterproofing material that can be used in urban construction and water supply. Taking into account the fact it is not always technically possible to carry out high-quality ramming when repairing channel walls, the task was to conduct an experimental study in order to determine the total moisture content of the mixture of PMM additive with soil. Experimental results of laboratory studies show that when PMM is added to the soil at a ratio of 30 g/kg under evaporation conditions, the mass of excess water in the substrate increases with time

    Experimental research on the filtration properties of an untamped mixture with “PMM” polymer mineral material

    No full text
    Polymermineral material "PMM" has multiple cycles of swelling and drying. It does not decompose under soil, biological and atmospheric influences and is environmentally safe. By adding the proportion of up to 30 g/kg of PMM additive to soil and tamping, we get a waterproofing material that can be used in urban construction and water supply. Taking into account the fact it is not always technically possible to carry out high-quality ramming when repairing channel walls, the task was to conduct an experimental study in order to determine the total moisture content of the mixture of PMM additive with soil. Experimental results of laboratory studies show that when PMM is added to the soil at a ratio of 30 g/kg under evaporation conditions, the mass of excess water in the substrate increases with time

    Abstracts of The Second Eurasian RISK-2020 Conference and Symposium

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    This abstract book contains abstracts of the various research ideas presented at The Second Eurasian RISK-2020 Conference and Symposium.The RISK-2020 Conference and Symposium served as a perfect venue for practitioners, engineers, researchers, scientists, managers and decision-makers from all over the world to exchange ideas and technology about the latest innovation developments dealing with risk minimization
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