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Документ Assessment of Light Transmission for Comfort and Energy Efficient Insolation by “Green Structures”(Springer, 2020-12-02) Tkachenko, Tetiana; Mileikovskyi, ViktorInsolation is one of the most important factors of human comfort and health in premises. Nevertheless, in a cooling period, the solar radiation brings additional heat gains decreasing the energy efficiency of buildings. The best practice is to allow the maximum solar radiation in heating and transition periods, and to limit it to the minimum permissible level during a cooling period. Usually, the problem is solved by technical measures, such as automated sun-blind-transformers, automatic jalousie or south orientation of glazing, equipped by a non-transformed canopy. In a previous work of the authors, a solution using “green structures” with deciduous plants was proposed. It avoids automation, allows using the most of orientations for glazing, does not decline the view, provides emotional comfort by the most natural appearance, and also improves the sanitary conditions by phytoncides. The goal of the work is the provision of minimum normative insolation in a cooling period by the design of a “green structure”. A geometric model is used for the sunrays, which passed through the planting. The model considers the shape of plant crowns and light transmission through them avoiding direct simulation of the shape of each leaf. An approach for the simple determination of the light transmission through different plants without special apparatus is proposed. The light transmission through different plant crowns was determined for different plants, which can be used in “green structures”. The best practice is a combination of plants with dense and openwork crowns.Документ Agrocenoses Air Improvement For Longer and Healthier People Life(Latvia University of Life Sciences and Technology, 2023-05-24) Tkachenko, Tetiana; Mileikovskyi, Viktor; Satin, Ihor; Ujma, AdamIn 2019, 99% of people in the world lived in areas violating WHO’s recommended air quality indicators. By WHO’s estimation, in 2019, air pollution caused 4.2 million premature deaths worldwide. The most harmful are PM2.5 particles, which penetrate the blood through the aerogematic barrier causing cardiovascular and respiratory diseases and cancer. PM10 can pass deeply into the lungs, but they are not so harmful. People always believed that rural air is healthy. Research at the University of Minnesota showed that 18 000 Americans die every year due to air pollution by agriculture, primarily, ammonia (NH 3) from the decomposition of fertilizers and livestock waste (12.4 thousand deaths), and PM2.5 particles (4.8 thousand deaths). In polluted areas, plants have more aggressive allergenic pollen. Agricultural waste management and optimization of landscapes are effective ways of solving the problem. In this work, solutions are proposed to improve the air safety of agrocenoses. Minimization of contact of waste with air and its utilisation as soon as possible allows for avoiding decomposition. Converting to gasification boilers/ovens avoids releasing PM2.5 by heating. In addition, plants capable of purifying the air from relevant pollutants should be introduced in agrocenoses. The places for planting are forest protection strips, free places near roads, residential and administrative buildings, etc. In particular, the use of hedges with such plants can provide a local oasis of clean air around houses. In the case of dense land use and lack of free space, it is possible to introduce “green structures” on buildings. An assortment of plants for different regions of Ukraine is offered.Документ Agrocenoses Air Improvement for Longer and Healthier People Life(Latvia University of Life Sciences and Technologies. Faculty of Engineering, 2023-05) Tkachenko, Tetiana; Mileikovskyi, Viktor; Satin, Ihor; Ujma, AdamIn 2019, 99% of people in the world lived in areas violating WHO’s recommended air quality indicators. By WHO’s estimation, in 2019, air pollution caused 4.2 million premature deaths worldwide. The most harmful are PM2.5 particles, which penetrate the blood through the aerogematic barrier causing cardiovascular and respiratory diseases and cancer. PM10 can pass deeply into the lungs, but they are not so harmful. People always believed that rural air is healthy. Research at the University of Minnesota showed that 18 000 Americans die every year due to air pollution by agriculture, primarily, ammonia (NH 3) from the decomposition of fertilizers and livestock waste (12.4 thousand deaths), and PM2.5 particles (4.8 thousand deaths). In polluted areas, plants have more aggressive allergenic pollen. Agricultural waste management and optimization of landscapes are effective ways of solving the problem. In this work, solutions are proposed to improve the air safety of agrocenoses. Minimization of contact of waste with air and its utilisation as soon as possible allows for avoiding decomposition. Converting to gasification boilers/ovens avoids releasing PM2.5 by heating. In addition, plants capable of purifying the air from relevant pollutants should be introduced in agrocenoses. The places for planting are forest protection strips, free places near roads, residential and administrative buildings, etc. In particular, the use of hedges with such plants can provide a local oasis of clean air around houses. In the case of dense land use and lack of free space, it is possible toДокумент Precise Explicit Approximations of the Colebrook-White Equation for Engineering Systems(Springer, 2020-08-17) Mileikovskyi, Viktor; Tkachenko, TetianaModern automated engineering systems have variable hydraulic/aero- dynamic conditions with Reynolds number from zero to hundred thousand with a wide range of roughness. Simple approximations of the Colebrook-White equa- tion cannot give enough precision. The aim of the work is a universal simple precise approximation of the Colebrook-White equation. The methods are se- lected by the analysis of the equation curve. In the whole range of turbulent flow, it is near to linear. Thus, Newton’s method is very effective. The algorithm is proposed for getting high-precision approximations. The results are two simple explicit ones for rough and careful calculations with a deviation of 5.36 % and 0.00072 % in a wide range of parameters. It is shown on the examples of the objects: the highest building “Biotecton” and researches of “green roofs” in a wind tunnel. The scientific novelty is that we scientifically grounded the effective usage of Newton’s method, which provides new universal, precise and simple explicit approximations of Colebrook-White equation. The practical value is that the approximations are covered different practical tasks of hydraulic and aerody- namic calculations in the whole range of turbulent flow.Документ Research of Deformation of Valve Throttling Characteristics under Gravitational Influence in Hydraulic Systems(Wydział budownictwa Politechniki częstochowskiej, 2019-12-23) Mileikovskyi, ViktorControl valve operation influences the efficiency of hydraulic systems. The deformation of the throttling characteristics in control valves by hydraulic resistances in a single-circuit regulated circuit is well studied. Nevertheless, there are other significant reasons for the deformation. This paper will focus on gravitational influences. The results show significant deformations. They are described by multiplying the valve authority by 0.6-1.7.Документ Field Study of Air Quality Improvement by a “Green Roof” in Kyiv(Sciendo, 2019-03) Tkachenko, Tetiana; Mileikovskyi, Viktor; Ujma, AdamCurrently, a very big problem of cities in Europe and the world is air pollution with combustion products of car fuels, generation of heat and electricity. These impurities affect the microclimate of cities significantly. Pollution not only affects the area outside buildings, but getting into their interior through ventilation systems, which has an adverse effect on the indoor environment of buildings. High concentrations of CO2, cause a weakening of concentration in working people, which affects the deterioration of safety and work efficiency. For assessing air quality improvement on "green roofs", a field study of CO2 content has been carried out on the "green roof" of a four-storey building, on a completely identical non-greened building, and on a highway with high-density traffic near them in Kiev. It was found that greening the roof significantly reduces the CO2 content from 501 ppm on the road and 452 ppm on the roof without protection to 410-415 ppm. It improves the conditions in which people work and restДокумент New Approach for Refined Efficiency Estimation of Air Exchange Organization(Science Publishing Corporation, 2018) Dovhaliuk, Volodymyr; Mileikovskyi, ViktorIn the modern conditions, energy efficiency is one of the most important world problems. One of the important factors influencing the overall energy efficiency of buildings is air distribution in rooms. Literature review shows different options of efficiency estimation of air exchange with significant limitations. Some of them have non-obvious physical meaning. Certain of them do not take into account possible room zoning. Consideration of turbulence intensity in the efficiency estimation was not found. In this work, we propose an approach to estimate the air exchange efficiency in different kind of rooms. It is a relation of minimum room demands and inlet air potentials. Additional definitions are introduced for the parameters and demands estimation. The mechanical energy of the air is used for the estimation, which includes the energy of averaged motion and turbulent pulsation. Special approach is offered for turbulence intensity computation for energy calculations. The example of efficiency estimation of air exchange in a museum room with constant air volume system of air conditioning is solved.Документ New Approach for Estimation of Zonal Efficiency of Air Exchange Organization(Science Publishing Corporation, 2018) Dovhaliuk, Volodymyr; Mileikovskyi, ViktorEnergy efficiency of buildings is dependent on air exchange organization. There are different methods for efficiency estimation of it. As it is shown in literature review, they have significant limitations including non-obvious physical meaning, which cause problems in validation of the results. Certain of them are not acceptable for zonal ventilation in rooms. Previous author’s work introduces new approach for the efficiency estimation of air exchange in a single-zone or multi-zonal rooms, which has obvious physical meaning – relation of demands and supplied potentials. It provides the efficiency value for whole room only. In this work, by the similar approach, a method is proposed for estimation of zonal air exchange efficiency in different kind of rooms for each occupied zone separately. Additional definitions are introduced for the parameters and demands estimation in each occupied zone. The example of efficiency estimation of air exchange in a museum room with constant air volume system of air conditioning is solved. Sheltering of the keeping zone is recommended for the maximum air exchange efficiency.Документ The Macrostructure Analysis of the Turbulent Mixing Boundary Layer Between Flows with the Same or Opposite Direction(Vilnius Gediminas Technical University, 2014) Mileikovskyi, ViktorThe approach to calculate large-scale vortexes boundary layer using approach of Professor A. Tkachuk is offered. It based on geometrical analysis of idealized macrostructure shown as a growing or constant radius vortex sheet. The small vortices in flows with a large-scale macrostructure plays secondary roles because they have incommensurably less energy than big vortices. They can be eliminated from consideration. We specify the velocity and temperature profile that differs from the jet boundary layer profile and better coincides with experiment. We find a growth law for a free boundary layer and length of currents cores. This approach help us to solve the actual task for energy efficient heating systems. We found the heat exchange coefficient between flows. It allows simulating the back flow effect in onepipe radiator nodes. The results of calculations coincides with well-known literature data.Документ Geometric Analysis of Turbulent Macrostructure in Gets Laid on Flat Surfaces for Turbulence Intensity Calculation(University of Belgrade, Faculty of Mechanical Engineering, 2017) Gumen, Olena; Dovhaliuk, Volodymyr; Mileikovskyi, Viktor; Lebedieva, Olha; Dziubenko, VolodymyrEuropean Norms for ventilation contain turbulence intensity requirements in rooms. One of the determining factors is turbulence intensity in ventilation jets. We found an approach for geometric analysis of turbulent macrostructure for subsonic flows with large-scale vorticity i.e. ventilation jets and boundary layers between flows. This approach requires building of simplified turbulent macrostructure chart and performing geometrical analysis of it. In previous works, using the approach we analytically found averaged characteristic of free jets, jets in flows and jets laid on different shape surfaces without requirements of any experimental data. The results of geometrical analysis of heat transfer between flows are used in Ukrainian norms. In this work we found turbulence intensity of wall jets on flat surfaces such as room walls or ceiling without any experimental values. The results coincide with known experimental data and may be used in flow calculation in rooms.