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The formation of high and stable yields is the main value of sowing peas (Pisum sativum L.) as a leguminous crop. The aim of the research was to study the influence of plant growth regulators on the processes of growth and development, formation of productivity, and grain quality of peas. The study of the influence of plant growth regulators on the productivity and quality indicators of peas was conducted according to the following scheme: control (without treatment with preparations), at the budding stage treatment with Humifield VR-18 w.s. (0.4 L ha-1), at the pod formation stage treatment with Fulvigrin Bor (0.5 L ha-1), at the budding stage treatment with Humifield VR-18 w.s. (0.4 L ha-1) + at the pod formation stage treatment with Fulvigrin Bor (0.5 L ha-1). The maximum yield was obtained in the variant with treatment of pea plants at the budding stage with Humifield VR-18 + at the pod formation stage with Fulvigrin Bor, amounting to 3.81 t.ha-1. According to the research results, the highest protein content was obtained from treatment at the budding stage with Humifield VR-18 + at the pod formation stage with Fulvigrin Bor - 23.2%. Based on the research results, it was established that to obtain a pea yield of 3.81 t.ha-1 with a protein content of 23.2%, it is proposed to use plant growth regulators at the budding stage with Humifield VR-18 + at the pod formation stage with Fulvigrin Bor. [ABSTRACT FROM AUTHOR]

This research explores the hydrodynamic processes within the flow section of a low-flow thermopressor as a jet-type heat exchanger that utilizes the instantaneous evaporation of highly dispersed liquid in accelerated superheated gas flow resulting in reducing gas temperature with minimum resistance losses in contrast to conventional surface heat exchanger. The efficiency of thermopressor, as a contact heat exchanger, is highly dependent on the design of the flow section and the water injection nozzle. Geometric characteristics perform a crucial role in shaping gas-dynamic processes along the length of the thermopressor's flow section, influenced by resistance losses and local resistance in the tapering and expanding channel segments. Therefore, the optimum thermopressor design has to ensure minimize pressure losses. Using Computational Fluid Dynamics (CFD), the prototype thermopressor models were simulated and the results were compared with experimental data. The empirical equations for local resistance coefficients of thermopressor diffuser and confuser were received to evaluate the impact of various design parameters. The obtained local resistance coefficients for the confuser ranged from 0.02 to 0.08 and for the diffuser - from 0.08 to 0.32. The practical recommendations on geometric and operating parameters and characteristics for enhancing the efficiency of hydrodynamic processes in thermopressor flow part were given. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The experiment studied the effectiveness of fertilizers in the foliar application of Rhizum, Leanum, and Gumisil-A in the field of barley which contain organic substances, macro- and micronutrients, amino acids, phytohormones. Of the three fertilizers, only Leanum contained nitrogen-fixing, phosphorus-forming, and potassium-mobilizing, lactic acid bacteria, decomposers, beneficial fungi. Soil of the experimental plot has low content of humus and nitrogen, medium content of labile phosphorus and exchangeable potassium with pH H2O 6.7. The highest yield was obtained with Leanum, exceeding the control without foliar application by 10.2%. As a result, using Leanum, the level of profitability is 6.44%. The application of Rhizum and Gumisil-A was not profitable due to the insignificant increase in yield and the cost of preparation, transportation and applying. Expensive fuel lubricating materials currently offset farmers' profits. [ABSTRACT FROM AUTHOR]

The grain industry in Ukraine is the most important component of the agro-industrial complex. At the same time, spring wheat grain production remains low and unstable due to insufficient efficiency of cultivation technology. The purpose of the research was to establish optimal seeding rates for soft spring wheat (Triticum aestivum L.) seeds of the Shirocco variety. The study of the influence of the seeding rate on the productivity and quality indicators of soft spring wheat was carried out according to the scheme: 3.5 million pcs ha-1, 4.0 million pcs ha-1, 4.5 million pcs ha-1, 5.0 million pcs ha-1; 5.5 million pcs ha-1; 6.0 million pcs ha-1. As a result of the research, it was found that the highest density of standing was obtained on the variant with a seeding rate of 6.0 million pcs ha-1 - 522 pcs m2 with plant preservation during the growing season of 86.8% (453.1 pcs m2). The maximum yield was observed on the variant with a seeding rate of 6.0 million pcs ha-1 - 5.63 t ha-1. At a seeding rate of 3.5, 4.0, 4.5, 5.0, 5.5 pcs m2 the yield was 4.07, 4.58, 4.76, 5.00, 5.30 t ha-1, respectively. According to the results of the research, it was studied that at a seeding rate of 6.0 million pcs ha-1, the highest yield of spring wheat grain was obtained - 5.63 t ha-1, and the maximum quality indicators of gluten and protein content at a seeding rate of 5.5 million pcs ha-1 - 25.5, 13.82%, respectively. [ABSTRACT FROM AUTHOR]

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 the practically instantaneous evaporation of highly atomized liquid droplets in accelerated superheated air, the pressure drop is reduced to a minimum. A further increase of the air pressure takes place in a diffuser. 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 is 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, and gas and internal combustion engines. [ABSTRACT FROM AUTHOR]

One of the most effective methods aimed to improving the environmental safety is fuel oil combustion in the form of specially prepared water-fuel emulsions. The combustion of water-fuel emulsion in internal combustion engines makes it possible to reduce a rate of low-temperature corrosion at wall temperatures below the dew point temperature of sulfuric acid vapor, to install a condensing lowtemperature heating surface in the exhaust gas boiler that leads to increase the efficiency of boiler. Therefore, it is of great importance to assess the effect of the presence of condensate (water, acid) and pollution on these surfaces on the processes of NOx, SO2 absorption from exhaust gases. Investigations of SO2, NOx and particulate matter emission were carried out on the experimental installation for fuel oil and water-fuel emulsion combustion with different water content. Using condensing heating surface enables to reduce the concentration of NOx and SO2 by 65 %. Experimental studies have shown that condensing heating surface ensures the capture of up to 30 % of particulate matter from the exhaust gas flow.

One of the most attractive reserves of enhancing the energetic efficiency of air conditioning systems (ACS) is to provide operation of compressors in closed to nominal modes by choosing the rational design refrigeration capacities and their distribution according to current thermal loading to provide closed to maximum annual refrigeration energy generation. Generally, the overall thermal load band of any ACS comprises the unstable load range, corresponding to ambient air precooling with significant load fluctuations, and a comparatively stable load part for further air conditioning from a threshold temperature to a target value. The stable thermal load range can be covered by operation of conventional compressor in closed to nominal mode, meantime ambient air precooling needs load modulation by applying a variable speed compressor. A proposed ACS enables a wide range of refrigerant flow variation without heat flux drop in air coolers and can be considered as advanced alternative to variable refrigerant flow systems.

The fuel efficiency of cooling air at the inlet of marine low speed diesel engine with water-fuel emulsion combustion by ejector chiller utilizing the heat of exhaust gas along the route line Mariupol– Amsterdam–Mariupol was estimated. The values of available refrigeration capacity of ejector chiller, engine intake air temperature drop and corresponding decrease in specific fuel consumption of the main diesel engine at varying climatic conditions along the route line were evaluated. Their values for water-fuel emulsion were compared with conventional fuel oil combustion.

The majority of integrated energy systems (IES) for combined electricity, heat and refrigeration generation, or trigeneration, are based on gas engines. The fuel efficiency of gas engines are strictly influenced by intake air temperatures. Practically in all IES the absorption lithium-bromide chillers (ACh) are applied for conversing the heat removed from the engine into refrigeration in the form of chilled water. The peculiarity of trigeneration in food industries is the use of chilled water of about 12°C for technological needs instead of 7°C as typical for ACh. This leads to a considerable great potential of engine intake air deeper cooling not realized by ACh, that can be used by ejector chiller (ECh) as the low temperature stage of two-stage absorption-ejector chiller (AECh) to provide engine cyclic air deep cooling and enhancing engine fuel efficiency. To evaluate the effect of gas engine cyclic air cooling the data on fuel consumption and power output of gas engine JMS 420 GS-N.L were analyzed.

The general trend to improve the fuel efficiency of gas turbines (GT) at increased ambient temperatures is turbine intake air cooling (TIAC) by exhaust heat recovery chillers The high efficiency absorption lithium-bromide chillers (ACh) of a simple cycle are the most widely used, but they are not able to cool intake air lower than 15°C because of a chilled water temperature of about 7°C. A two-stage hybrid absorption-ejector chillers (AECh) were developed with ejector chiller as a low temperature stage to provide deep air cooling to 10°C and lower. A novel trend in TIAC by two-stage air cooling in chillers of hybrid type has been proposed to provide about 50% higher annual fuel saving in temperate climatic conditions as compared with ACh cooling. The advanced methodology to design and rational distribute the cooling capacity of TIAC systems that provides a closed to maximum annual fuel reduction without oversizing was developed.

Cogeneration or combined heat and power (CHP) has found wide application in various industries because it very effectively meets the growing demand for electricity, steam, hot water, and also has a number of operational, environmental, economic advantages over traditional electrical and thermal systems. Experimental and theoretical investigations of the afterburning of fuel oil in the combustion engine exhaust gas at the boiler inlet were carried out in order to enhance the efficiency of cogeneration power plants; this was achieved by increasing the boiler steam capacity, resulting in reduced production of waste heat and exhaust emissions. The afterburning of fuel oil in the exhaust gas of diesel engines is possible due to a high the excess air ratio (three to four). Based on the experimental data of the low-temperature corrosion of the gas boiler condensing heat exchange surfaces, the admissible values of corrosion rate and the lowest exhaust gas temperature which provide deep exhaust gas heat utilization and high efficiency of the exhaust gas boiler were obtained. The use of WFE and afterburning fuel oil provides an increase in efficiency and power of the CPPs based on diesel engines of up to 5% due to a decrease in the exhaust gas temperature at the outlet of the EGB from 150 °C to 90 °C and waste heat, accordingly. The application of efficient environmentally friendly exhaust gas boilers with low-temperature condensing surfaces can be considered a new and prosperous trend in diesel engine exhaust gas heat utilization through the afterburning of fuel oil and in CPPs as a whole. [ABSTRACT FROM AUTHOR]