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Experimental study of dispersed flow in the thermopressor of the intercooling system for marine and stationary power plants compressors

Konovalov Dmytro, Kobalava Halina, Radchenko Mykola, Løvås Terese, Pavlenko Anatoliy, Radchenko Roman, Radchenko Andrii

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2024

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Vol. 72, nr 1

art. no. e148439

EN

This study investigates the use of a thermopressor to achieve highly dispersed liquid atomization, with a primary focus on its application in enhancing contact cooling systems of the cyclic air for gas turbines. The use of a thermopressor results in a substantial reduction in the average droplet diameter, specifically to less than 25 μm, within the dispersed flow. Due to practically instantaneous evaporation of highly atomized liquid droplets in accelerated superheated air the pressure drop is reduced to minimum. A further increase of the air pressure takes place in diffuser. In its turn, this allows for the compensation of hydraulic pressure losses in the air path, thereby reducing compressive work. Experimental data uncover a significant decrease in the average droplet diameter, with reductions ranging from 20 to 30 µm within the thermopressor due to increased flow turbulence and intense evaporation. The minimum achievable droplet diameter is as low as 15 µm and accompanied by a notable increase in the fraction of small droplets (less than 25 µm) to 40–60%. Furthermore, the droplet distribution becomes more uniform, with the absence of large droplets exceeding 70 µm in diameter. Increasing the water flow during injection has a positive impact on the number of smaller droplets, particularly those around 25 μm, which is advantageous for contact cooling. The use of the thermopressor method for cooling cyclic air provides maximum protection to blade surfaces against drop-impact erosion, primarily due to the larger number of droplets with diameters below 25 μm. These findings underline the potential of a properly configured thermopressor to improve the efficiency of contact cooling systems in gas turbines, resulting in improved performance and reliability in power generation applications. The hydrodynamic principles explored in this study may have wide applications in marine and stationary power plants based on gas and steam turbines, gas and internal combustion engines.

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Advanced fuel system with gaseous hydrogen additives

Shalapko Denys, Radchenko Mykola, Pavlenko Anatoliy, Radchenko Roman, Radchenko Andrii, Pyrysunko Maxim

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2024

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Vol. 72, nr 2

art. no. e148837

EN

The advancement of contemporary internal combustion engine technologies necessitates not only design enhancements but also the exploration of alternative fuels or fuel catalysts. These endeavors are integral to curbing the emission of hazardous substances in exhaust gases. Most contemporary catalyst additives are of complex chemical origins, introduced into the fuel during the fuel preparation stage. Nonetheless, none of these additives yield a significant reduction in fuel consumption. The research endeavors to develop the fuel system of a primary marine diesel engine to facilitate the incorporation of pure hydrogen additives into diesel fuel. Notably, this study introduces a pioneering approach, employing compressed gaseous hydrogen up to 5 MPa as an additive to the principal diesel fuel. This method obviates the need for extensive modifications to the ship engine fuel equipment and is adaptable to modern marine power plants. With the introduction of modest quantities of hydrogen into the primary fuel, observable shifts in the behavior of the fuel equipment become apparent, aligning with the calculations outlined in the methodology. The innovative outcomes of the experimental study affirm that the mass consumption of hydrogen is contingent upon the hydrogen supply pressure, the settings of the fuel equipment, and the structural attributes of the fuel delivery system. The modulation of engine load exerts a particularly pronounced influence on the mass admixture of hydrogen. The proportion of mass addition of hydrogen in relation to the pressure of supply (ranging from 4–12 MPa) adheres to a geometric progression (within the range of 0.04–0.1%). The application of this technology allows for a reduction in the specific fuel consumption of the engine by 2–5%, contingent upon the type of fuel system in use, and concurrently permits an augmentation in engine power by up to 5%. The resultant economic benefits are estimated at 1.5–4.2% of the total fuel expenses. This technology is applicable across marine, automotive, tractor, and stationary diesel engines. Its implementation necessitates no intricate modifications to the engine design, and its utilization demands no specialized skills. It is worth noting that, in addition to hydrogen, other combustible gases can be employed.

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Microbiological Activity of Soil Under the Influence of Post-Harvest Siderates

Mishchenko Yurii, Kovalenko Ihor, Butenko Andrii, Danko Yuriy, Trotsenko Volodymyr, Masyk Ihor, Radchenko Mykola, Hlupak Zoya, Stavytskyi Andrii

Journal of Ecological Engineering

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2022

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Vol. 23, nr 4

122--127

EN

The results of research on the activation of the microflora by using post-harvest green manure crops were presented. As a result of the conducted studies, the positive effect of sidereal crops of Raphanus sativum and Phacelia tanacetifolia on activity increase of microflora in black soil with little humus was revealed. Application of post-harvest siderates increased the number of non-sporous species of bacteria and actinomycetales, contributed to improvement of soil environment under the influence of siderates, which had a positive effect on creating more comfortable conditions for growing potatoes. The usage of green fertilizers had a positive influence on microbiology activity of soil.

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Efficiency analysis of the aerothermopressor application for intercooling between compressor stages by using CFD model

Kobalava Halina, Radchenko Mykola, Konovalov Dmytro

Journal of New Technologies in Environmental Science

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2021

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Vol. 5, nr 4

129--134

EN

A study of the aerothermopressor operation for air intercooling between the stages of a multistage compressor as part of a modern gas turbine (LMS100 brand from General Electric) was carried out in the article. A calculation method has been developed using numerical modeling for the evaporation of fine water droplets in the air flow. The main characteristics of the two-phase flow at the aerothermopressor outlet have been determined. It has been found that jet apparatus provides efficient atomization of the liquid, and hence, more efficient isothermal compression process in a high-pressure compressor. The aerothermopressor applying allowed to reduce the temperature of the compressed air between the compressor stages to 50-70°C. Such a decrease in temperature under the thermo-gas-dynamic compression conditions allowed to increase the pressure at the aerothermopressor outlet up to 12-28 kPa (4-9%).

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Enhancing the exhaust heat recovery in integrated energy plant

Radchenko Mykola, Radchenko Andrii, Mikielewicz Dariusz, Forduy Serhiy, Zubarev Anatolii, Khaldobin Viktor

Journal of New Technologies in Environmental Science

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2020

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Vol. 4, nr 4

157--165

EN

The efficiency of exhaust heat recovery in typical integrated energy plant on the base of reciprocating gas engines with absorption lithium-bromide chiller for combined electricity, heat and refrigeration supply of the factory Sаndorа-PepsiCо Ukraine is analyzed. The reserves of decreasing the heat exhausted into atmosphere are revealed on the base of monitoring data and their realization through conversion into refrigeration for cooling the engine cyclic air is proposed. Some scheme decisions of improved and innovative exhaust heat recovery systems providing deep heat conversing into refrigeration for engine cyclic air cooling are developeded.