bluuebunny/crossref_metadata_2025_split huggingface dataset:
ЭКОНОМИЧЕСКАЯ НЕОБХОДИМОСТЬ СОЗДАНИЯ МОДИФИКАЦИЙ ОТЕЧЕСТВЕННЫХ ВОЕННО-ТРАНСПОРТНЫХ САМОЛЕТОВ
Authors: Лось Александр Васильевич 
Published: August 2019

The state enterprise "Antonov" is one of the leaders in the world in the development and commissioning of modifications of transport-grade aircraft, including military transport aircraft. The cost of developing and mastering serial production of new MTA and aircraft engines is, as a rule, several billion dollars, so for the project to pay off, it is necessary to implement it through the creation and commissioning of modifications to the already existing basic options. This inevitably raises the problem of correct comparison of the operated MTA and its modifications.Currently, there is no acceptable methodology for determining the level of competitiveness of complex industrial products, including aviation. Product competitiveness is a complex concept that requires a multi-faceted assessment. An important component of such an assessment is the cost indicators of the newly created modification, such as: the cost of modifying a new aircraft, the cost of aircraft hours, hourly fuel costs, etc.The paper shows that the cost parameters of the modifications largely depend on the type of aircraft (light, medium or heavy) and on the year the modification was presented in the air transportation market.The analysis of changes in prices of domestic light, operational-tactical and heavy MTA in the comparative setting with competitors-analogues is given. It follows from the analysis that these domestic aircraft were competitive at their price until 2012, and now there is an economic problem of increasing their competitiveness by carrying out profound modification in the wing and in their power plant in these previously created aircraft.The solution of this problem is carried out by geometrical rearrangement of the wing (to improve its aerodynamic quality) and the replacement of cruise engines with lower specific fuel consumption. Modifications were created in this way: on the basis of An-32B – An-132D with specific fuel consumption of 223 g/t∙km, on the basis of An-148 – An-178 with specific fuel consumption of 222 g/t∙km and on the basis of An-70 – An-188 with a specific fuel consumption of 154 g/t∙km at maximum capacity.Considering that the cost of hourly fuel consumption takes about 70 % of the cost of an air-hour, the results obtained significantly increase the competitiveness of the above-mentioned MTA.
SELECTION AND OPTIMIZATION OF FUSELAGE COMPONENTS FOR MODERN AIRPLANES
Authors: Makarov Ihor Andriyovych , Ignatovich Sergey Romualdovich 
Published: August 2019

Nowadays the level of development of airplane materials shows the tendency of usage of advanced composite structures. However, these materials have plenty of advantages and disadvantages, the most crucial is the ability to absorb water from the environment and because of this layers of composite structures disbonded and consequently became useless. This issue demonstrates the limitation of usage of advanced composite structures. Despite this fact application of conventional materials (such as Aluminum or Titanium alloys) are limited by the weight of structure and manufacturability. In given article question of optimization for choosing of the airplane, the material is considered. The necessity to maintain equilibrium between minimal weight and appropriate strength pushes designers to develop new advanced materials, mechanical properties of which satisfy strict criteria of strength, despite lightweight of the material. The goal of this research elaborating work is to estimate the necessity of usage of advanced composite structures vs well known conventional materials. It was researched sizing and optimization of choosing of structural materials for the primary structure. On top of this, properties and peculiarities of conventional materials (such as Aluminum and Titanium alloys) and advanced composite structure. It was demonstrated that the usage of conventional materials for primary structure has a significant advantage in comparison with advanced composite structures. Additionally, manufacturability and maintainability of materials were discussed in the given article. As a result, the application of conventional materials for primary airplane structure is the most suitable way for the design of modern airplanes. Today, the structural designer no longer chooses a material solely based on its strength qualities, but on its proven ability to withstand minor damage in service without endangering the safety of the aircraft. The residual strength after damage, described as the toughness, is now uppermost in the engineer’s mind when he chooses alloys for airframes. Damage caused by fatigue is the main factor because it is difficult to detect and can disastrously weaken the strength of critical components. So whereas about a decade ago aluminum alloys looked as if they had reached a technical plateau, engineers have now been able to clarify their needs as a result of the work done on fracture mechanics, and metallurgists have changed their composition and treatment techniques to meet the new toughness requirements. The best option to consider the usage of both advanced composite structure (for secondary structures) and conventional material (for primary structures).
МАЛОИНЕРЦИОННЫЙ ТЕПЛООБМЕННИК АММИАК-АНТИФРИЗ ДЛЯ ИССЛЕДОВАНИЯ ПЕРЕХОДНЫХ ПРОЦЕССОВ В ЭЛЕМЕНТАХ ДВУХФАЗНОЙ СИСТЕМЫ ТЕРМОРЕГУЛИРОВАНИЯ СПУТНИКА
Authors: Годунов Артем Михайлович , Роговой Евгений Эдуардович , Орлов Роман Сергеевич , Турна Рустем Юсуфович 
Published: August 2019

Technical progress entails the use of more powerful equipment on satellites. In connection with the growth of heat generation onboard the spacecraft, the task is to develop thermal control systems based on two-phase mechanically pumped fluid loop (2PMPFL). The advantage of such systems is the ability to transport a greater amount of heat, reduced to a unit of flow, than when using circuits with a single-phase coolant. The study of two-phase thermal control systems in terrestrial conditions is difficult because gravity affects the hydraulics and heat transfer of two-phase flows. Particularly difficult is the study of transients. This article presents the results of tests of a recuperative heat exchanger, which allows to study transient processes in 2PMPFL with high accuracy.It was designed and manufactured the heat exchanger of simple “tube in tube” type design. The thermal characteristics of the heat exchanger were determined on the experimental stand, which is a prototype of a closed-type 2PMPFL with ammonia coolant. Single-phase “liquid” modes, two-phase modes with low mass vapor content (up to 0.04), and single-phase transient modes were investigated. It has been experimentally determined that a heat exchanger under given conditions is capable of removing up to 1323 W of heat in a single-phase mode and up to 1641 W of heat - when operating in a two-phase mode. The data obtained in the course of the experiments allowed us to select the most appropriate known correlation for calculating the stationary characteristics of the heat exchanger with an error not exceeding 5%, which is a high indicator of accuracy for engineering calculations.The heat exchanger has low thermal inertia. The conclusion is relevant for the range of parameters: the ammonia temperature at the inlet is 24...60 ⁰C; antifreeze inlet temperature 5… 16 ⁰C; ammonia mass flow rate 8...17 g / s; mass flow rate of antifreeze 1...4 kg/min.Due to the low thermal inertia of the heat exchanger, it can be used to study transients with the rate of change of the coolant temperature at the inlet up to 1.85 K / min. You can use the stationary method of thermal calculation, i.e. calculate the transient process in the quasi-stationary approximation.
ЗАСТОСУВАННЯ ГАЗОДИНАМІЧНОГО ОХОЛОДЖЕННЯ В СИСТЕМАХ РЕЦИРКУЛЯЦІЇ ВІДХІДНИХ ГАЗІВ СУДНОВИХ ДИЗЕЛІВ
Authors: Коновалов Дмитро Вікторович 
Published: August 2019

There are many ways and methods to reduce exhaust gases emissions on modern ships. One of the most effective ways to reduce NOx and SOx emissions is to use of exhaust gas recirculation (EGR technology). The EGR system disadvantage is an increase in back pressure through additional pressure losses in the scrubber and heat ex-changer, which entails an engine fuel efficiency deterioration. Creating a reliable and efficient heat exchanger for cooling recirculation gases is a complex task due to deposits and pollution emitted by these gases. In the pre-sent work, the jet apparatus effectiveness named aerothermopressor is analyzed in the scheme with exhaust gases recirculation of the ship low-speed two-stroke engine. Aerothermopressor is a two-phase jet for contact disperse cooling, in which by increasing the heat from the gas stream the gas pressure and cooling are increased. The calculation of the characteristics of the engine was carried out, both in nominal, and in operating modes and in all possible range of partial loads. The installation of the aerothermopressor before the scrubber is pro-posed, which allows reducing engine thermal load. Increasing the pressure in the aerothermopressor by 0.2-0.4 ∙ 105 Pa (6-12 %) allows reducing the back pressure in the gas exhaust system and thus reducing the load on the exhaust gas recirculation fan and when the engine load is higher than 75% in the cold zone, the fan is not need-ed, which additionally allows to reduce the specific fuel consumption. The parameters of the exhaust gases that are going to be recirculated and the processes of their gas-dynamic cooling in the aerothermopressor are based on the developed technique and program using the thermodynamic and gas dynamics equations. The proposed scheme-design solution allows at a high environmental friendliness of the existing exhaust gas recirculation sys-tem to provide a certain reduction in specific fuel consumption. It was determined that the engine specific fuel consumption has been decreasing when the aerothermopressor is used to Dge = 2.5-3.0 g/(kW·h) (1.5-1.7%).
ПАРАМЕТРИЧЕСКАЯ ОПТИМИЗАЦИЯ ПО КРИТЕРИЮ ОБЪЕМА ДВУХСТУПЕНЧАТОГО ПЛАНЕТАРНОГО МЕХАНИЗМА ТИПА AI–II
Authors: Матусевич Владимир Анатольевич , Шарабан Юрий Владимирович , Шехов Александр Владимирович 
Published: August 2019

The task of parametric optimization on the criterion of total volume is considered for the two-stage planetary mechanism of type AI–II. The objective function of optimization is built as a sum of two dimensionless parametric functions of volume (analogs of volume) of the separate stages of planetary mechanism of type AI–II. Construction of analogs of volume of simple planetary mechanisms of type AI and II, corresponding the first and second to the stages of planetary mechanism of type AI–II, it is based on their presentation as conditional disks. Thus the volume of the conditional disk is equivalent to the volume of a simple planetary mechanism. The mathematical model of analogs of the volume is built taking into account the terms of the durability of the toothed hooking of the sun gear and planetary gears of simple planetary mechanism, and also taking into account an area possible his transmission relation. Considering terms of contact and bending durability of the toothed hooking, get the analogs of volume at a calculation on contact and bending to durability. Depending on the condition of durability (contact or bending) and type of simple planetary mechanism the analog of his volume appears as a parametric function of corresponding parameters of his kinematics diagram. As parameters transmission relation attitude of simple planetary mechanism, parameters of bringing a mechanism over, toward a conditional disk, and also the relation of reference diameters of planetary gears of the mechanism is chosen. An analysis over of influence of each is brought of parameters of the function of analog of volume on the pattern of behavior to it. On the basis of this analysis of function of analogs of volume of the stages of planetary mechanism of type AI–II appear as parametric functions of the guided parameters. For the simple planetary mechanism of type AI one guided parameter is chosen, namely transmission relation of mechanism. For the guided parameters of function of analog of volume for the simple planetary mechanism of type II a transmission relation and relation of reference diameters of planetary gears of mechanism are chosen, i.e. two guided parameters. Offered approach for the decision of optimization task, based on research of differential properties of objective functions of volume (analogs of volume) of the separate stages of planetary mechanism of type AI–II. It is given the example of the optimal designing of construction of minimum volume of planetary mechanism of type AI–II.
ОПРЕДЕЛЕНИЕ КОЭФФИЦИЕНТА КОНВЕКТИВНОГО ТЕПЛОПЕРЕНОСА В ГИДРОАККУМУЛЯТОРЕ С ТЕПЛОВЫМ РЕГУЛИРОВАНИЕМ ДЛЯ УСЛОВИЙ НЕВЕСОМОСТИ
Authors: Коваль Полина Сергеевна , Решитов Эдем Русланович , Турна Рустем Юсуфович 
Published: August 2019

In the modern world with the increasing power of spacecraft heat dissipation, the need has arisen to use efficient heat removal systems with two-phase heat transfer contours. Their advantages are determined by the fact that they can carry a much larger amount of heat per unit of consumption than when using a single-phase coolant. The energy consumption of the pump for pumping the coolant is insignificant, and the use of heat exchange during boiling allows you to maintain the temperature of objects almost the entire length of the circuit close to the saturation temperature. All heat transfer processes occurring with a change in the state of aggregation of a substance (boiling, condensation) occur much more intensively than during convective heat exchange in a single-phase liquid. A feature of this system is the change in mass of the coolant in the circuit when changing the operating modes of the two-phase heat transfer system. To regulate the amount of coolant in the circuit, as well as to maintain a predetermined pressure (boiling point), a hydraulic accumulator with thermal regulation (HCA) is used. The actual processes of heat and mass transfer in HCA are non-equilibrium, which complicates the calculation of the thermal control system. This paper describes the concept of a nonequilibrium mathematical model for calculating heat and mass transfer processes in HCA. It is shown that the nonequilibrium of processes can be taken into account by the convective heat transfer coefficient “k” in the mathematical model of HCA: k = 1 corresponds to the absence of convection; k > 100 corresponds to an equilibrium process. Based on the analysis of the flight space experiment for heating HCA, a prediction was made of the value of the convective heat transfer coefficient k under zero-gravity conditions. To assess the influence of the “k” value on the process of regulating the two-phase heat transfer contour under weightless conditions, it is recommended to use the values k = 30 ± 15. In ground-based experiments at high-intensity convection in HCA, processes are much more equilibrium than in zero gravity. It is concluded that the equilibrium process (high values of k) can be considered as more conservative concerning the regulatory process in weightlessness.
УЛУЧШЕНИЕ ЭКОЛОГИЧЕСКИХ ПОКАЗАТЕЛЕЙ ДВИГАТЕЛЯ ВНУТРЕННЕГО СГОРАНИЯ ИСПОЛЬЗОВАНИЕМ СКРУББЕРНЫХ ТЕХНОЛОГИЙ И ЭФФЕКТА "МИКРОВЗРЫВОВ" КАПЕЛЬ ВОДОТОПЛИВНОЙ ЭМУЛЬСИИ
Authors: Корниенко Виктория Сергеевна , Радченко Роман Николаевич , Щербак Юрий Георгиевич 
Published: August 2019

The rules of international organizations in the field of environmental protection are consistently tightening the requirements for the level of harmful emissions into the atmosphere from both stationary and ship power plants (SPP). To ensure this level, it is necessary to use wet scrubber technology and a hybrid system when used simultaneously or sequentially. The study aims to develop a wet scrubber scheme for сomplex exhaust gas cleaning system for an internal combustion engine (ICE). Experimental studies have shown that at the end of the combustion zone of a water-fuel emulsion (WFE) with a water content of 30 % due to the influence of intense turbulence created during microexplosions of WFE droplets in the zone of active combustion in gases, an equimolar NO2 : NO ratio is created automatically (or almost this). It is required to enhance the absorption properties of exhaust gases in front of the scrubber. It is established that when WFE is burnt with water content Wr = 30 %, the content of toxic ingredients in the exhaust gases in front of the scrubber will be at a much lower level compared to the cleaning system at Wr = 2 %. A scheme of a wet scrubber has been developed, which allows to clean exhaust gases from three toxic exhaust gas ingredients simultaneously with heating water to exhaust gas boiler and drying wet gases after a wet scrubber due to the heat of the intermediate coolant. It has been established that the heat of this intermediate coolant is sufficient not only to heat the feed water of the exhaust gas boiler, but also to provide a hot water supply system for the ship, since in the scrubber, as a result of exhaust water vapor condensation up to 8 % of the lower combustion heat of the fuel burned power units. Analysis of the calculated studies showed that the using of a wet scrubber reduces the NOx content from 258 ppm to 52 ppm, SO2 - from 107 ppm to 22 ppm, CO2 - from 3.1 % to 0.93 %. The developed wet scrubber scheme can be used to clean the exhaust gases of internal combustion engines from toxic ingredients and to provide the necessary level of exhaust gas purification recommended by the IMO (International Maritime Organization).
РЕЗУЛЬТАТЫ ОЦЕНКИ ДИНАМИЧЕСКОЙ УСТОЙЧИВОСТИ К ДОЗВУКОВОМУ ФЛАТТЕРУ ЛОПАТОЧНЫХ ВЕНЦОВ КОМПРЕССОРОВ НЕКОТОРЫХ АВИАЦИОННЫХ ГАЗОТУРБИННЫХ ДВИГАТЕЛЕЙ
Authors: Зиньковский Анатолий Павлович , Стельмах Анатолий Леонидович , Кабанник Сергей Николаевич 
Published: August 2019

The paper outlines the results of the investigation on the verification of the express method of prediction of dynamic stability for subsonic flutter using the blade assemblies of individual stages of the compressor of some types of aircraft gas-turbine engines at different modes of their operation. The paper gives a brief overview of the basic concepts of the developed express estimation method, possibilities of the determination of the stability limit for the blade assemblies for a subsonic flutter, as well as the results of the assessment of the dynamic stability of the compressor stages of some modern aircraft gas-turbine engines. Firstly, the reduced frequencies of vibrations of the blade assemblies under investigation and their critical values coincide practically. The mentioned critical values were determined from the test data for the straight cascades of the blade airfoils corresponding to two sections of the height of the blade airfoil portion. Hence it follows that the task can be solved employing only gas-dynamic parameters of the flow for one of the sections of the airfoil within the specified range of its height. Secondly, the prediction of dynamic stability for the subsonic flutter of the blade assemblies of separate compressor stages of some types of aircraft gas-turbine engines and the comparison of the obtained results with the data of bench tests, as well as the data obtained using other methods, were made. It was implied that the developed method allows one to determine the flutter limit with high accuracy, as well as make an optimal selection of the values of the reduced frequency of the blade vibrations for the specified range of the angle of attack of the sections of the blade assemblies upon the condition of its occurrence. Thirdly, the possibility to determine the nature of vibration excitation for the blade assemblies is considered using the analysis of the initiation of cracks in the blade root of the first compressor stage of the high-pressure gas-turbine engine. Moreover, it is shown that at large angles of attack (≥ 10°) an insignificant displacement of the dynamic stability limit of the blade assemblies may occur in the direction of large values of the reduced frequency of their vibrations.
ВОЗМОЖНОСТИ ПРОГРАММНОГО КОМПЛЕКСА ДЛЯ ПРОЕКТИРОВАНИЯ ИМПУЛЬСНЫХ ТЕХНОЛОГИЙ МЕТОДОМ «БЛИЖАЙШЕГО СОСЕДА»
Authors: Третьяк Владимир Васильевич , Онопченко Антон Виталиевич , Федорова Анастасия Сергеевна 
Published: August 2019

In aircraft and engines details are used for implementation of difficult functions: providing of bearing strength of knots and good on the whole; differentiations of different environments – working and surrounding, having different parameters on pressure, temperature, closeness, speed, providing of minimum losses at the flowline around by threads of different environments and etc Power functions in most cases execute the details of obolochkovoy form or inflexibilities flat with elements, and functions of differentiation of environments – details with the channel surfaces. The given details can be made methods of the impulsive stamping. A program complex is developed, allowing to design impulsive technologies by the method of «next-door neighbour». Data about details are presented at a few informative levels – level of general form, fragments and additional elements, relief and exactness. At level general form to present data about details as an aggregate of three basic components: bottom, walls and flanets. On the given components fragments are executed and additional elements, perceiving loading, and also local elements for placing and fastening in them of sensors, devices, key units. A program complex allows to use a few possible variants of planning: without the change of structure of analogue and parametricheskoy tuning (method of the complete borrowing of analogue); without the change of structure of analogue (method of borrowing of analogue with the parametricheskoy tuning); with the change of structure of analogue. At the near analogue of detail a revision in analogue is taken mainly to adjustment of the modes of treatment. In default of such, a few analogues are used, and all analogue is exposed to the revision and its structural units on the basis of synthesis of new technological decisions. For the tract steady in production of land of details with the near designer-technological properties a model technological process is created for the complex detail, in which are reflected basic to the aggregate of surfaces and their elements, characteristic for all tract of land. In the program a few algorithms are used of search of «next-door neighbour». Algorithms are used to the program on the Evklid distance, on the square of Evklid distance, on the distance Chebisheva and sedate distance Minkovskogo. Basic algorithms are presented, screen forms of program complex and possibilities of program complex.