scholarly journals ВЗАИМОВЛИЯНИЕ ИЗМЕНЕНИЙ В СИЛОВОЙ УСТАНОВКЕ И В ГЕОМЕТРИИ КРЫЛА У ЛЕГКИХ ВОЕННО-ТРАНСПОРТНЫХ САМОЛЕТОВ

2020 ◽  
pp. 15-20
Author(s):  
Александр Васильевич Лось
Keyword(s):  
Power Plant ◽  
Carrying Capacity ◽  
Load Capacity ◽  
Scientific Basis ◽  
Flight Performance ◽  
Load Range ◽  
Continuous Growth ◽  
Transport Aircraft ◽  
Military Vehicles ◽  
Matching Models

An analysis of the main directions of the development of military transport aircraft (MTА) showed that, as applied to light military vehicles, a tendency to increase their carrying capacity in a narrow range corridor was revealed. The required increase in carrying capacity inevitably entails an increase in the starting mass of modifications, which leads to a deterioration in take-off and landing characteristics, and acts as a serious limitation, especially for light military-technical complexes, according to their conditions of basing. The solution of such problematic problems can be carried out using profound modification changes in the system of load-bearing surfaces of the modification, and also in its power plant, the scientific basis for the coordination of which is based on three principles: continuous growth of performance modifications; geometric rearrangement of the wing, taking into account its ellipticity coefficient; coordination of the parameters of the power plant with an increased load capacity of the modification and with the modified geometry of its wing. The development of such models is based on the use of the weight balance equation, taking into account the fact that the components of the starting mass are not statistically determined, but there are functions of target parameters, such as load capacity, range, speed characteristics, parameters of marching engines, etc. Taking into account restrictions on take-off weight, load capacity, take-off length, etc., models were obtained for evaluating the “load-range” characteristics of light military-transport vehicles, as well as the take-off value for one engine that failed. The performance assessment of the obtained models was tested on modifications of the domestic An-26, An-32, and An-32B aircraft by evaluating their “load-range” characteristics when replacing their marching engines with increased power. An analysis of these dependencies showed that the process of matching the wing parameters and changes in the power plant (with the same external contours) leads to a significant increase in carrying capacity, and hence, flight performance. An analysis of the comparative assessment of the parameters of the basic version of the An-26 with its modifications An-32 and An-32B also revealed that the matching models obtained in the work allow already at the stage of preliminary designing more productive modifications to form their main parameters that meet the requirements of the customer.

scholarly journals НОВЕ ПОКОЛІННЯ ВІТЧИЗНЯНИХ ВІЙСЬКОВО-ТРАНСПОРТНИХ ЛІТАКІВ

2020 ◽  
pp. 5-11
Author(s):  
Олександр Васильович Лось ◽  
Віктор Іванович Рябков
Keyword(s):  
Power Plant ◽  
Carrying Capacity ◽  
Maximum Load ◽  
The State ◽  
Light Transport ◽  
Aviation Industry ◽  
Transport Aircraft ◽  
Comprehensive Program ◽  
The Creation ◽  
Passenger Aircraft

According to European experts, only the USA and Ukraine can produce a full line of military transport aircraft of all weight categories (light, medium, and heavy).At the time of the creation of the “State comprehensive program for the development of the aviation industry of Ukraine until 2020” Ukraine had:- light transport aircraft An-32 with a carrying capacity of 6.7 tons and a range of 2500 km;- operational and tactical military passenger aircraft (MPA) with a carrying capacity of 30 tons and a range with a full load of 4300 km;- regional passenger aircraft Аn-148-100В (An-148-100V) with a maximum payload of 9.0 tons and a range of 2600 km.Through the efforts of the entire Antonov Company team, prototypes have been designed, manufactured, and partly tested such modifications as An-132D, An-178, and An-188, the implementation of which is based on the use of the new “Methodology for Designing Military Transport Aircraft Modifications, Taking into Account Profound Changes in the Wing and in the Power Plant”.Given the scientific provisions of this "Methodology ...":- based on the An-32 aircraft, a modification of the light aircraft MTA An-132D with a carrying capacity of 9.1 tons, with an increased range of up to 2400 km and with a fuel efficiency index higher than that of the base model, has been created through profound changes in the power plant, i.e. using PW150 engines and an increase in fuel mass by one and a half times;- based on the An-148 passenger aircraft, by means of profound changes both in the wing geometry and in the power plant, a modification of the mid-range military transport An-178 aircraft has been created with a carrying capacity of 18 tons and a range with a maximum load of 1.200 km, which provides a niche to this modification not occupied by competitors;- ensuring the complete superiority of the An-188 modification among analog competitors is also based on the profound changes: replacement the D27 turboprop engine for a turbofan CFM LEAP-1Ain the power plant; the use of a discrete geometric twist of the local wing chords, which ensured the aircraft range of 3200 km with a payload of 47 tons and significantly increased its combat readiness due to the use of turbofan engines.A comparative assessment of these military transport aircraft with their basic models shows that the team of the Antonov Company has honorably implemented the “State comprehensive program for the development of the aviation industry of Ukraine until 2020” in part of the creation of a new generation of military transport aircraft that is competitive in all technical and economic parameters.

scholarly journals ДОСВІД І ОСОБЛИВОСТІ ФОРМУВАННЯ МАСОВИХ ХАРАКТЕРИСТИК МОДИФІКАЦІЙ ВАЖКОГО ТРАНСПОРТНОГО ЛІТАКА

2021 ◽  
pp. 4-14
Author(s):  
А. З. Двейрин
Keyword(s):  
Distinctive Feature ◽  
Carrying Capacity ◽  
Mass Gain ◽  
Flight Performance ◽  
Wing Area ◽  
Flight Tests ◽  
Transport Aircraft ◽  
Class 1 ◽  
Design Production ◽  
Special Approach

Heavy transport aircraft are built and operated by US airlines (C-5A, C-5B, B-747-400), the European Concern Airbus (A-380), and the ANTONOV domestic state-owned enterprise. Such heavy aircraft as An-22, An-124 and An-225 have received worldwide recognition as the most efficient in their class [1, 2, 3]. It should be noted that such outstanding compatriots as O. K. Antonov, P. V. Balabuev, S. A. Bychkov, V. I. Tolmachev, V.F.Eroshin, O.K.Bogdanov made a decisive contribution to their improvement (including formation of mass characteristics).The main path of development of domestic heavy transport aircraft is to create modifications that meet the ever-increasing requirements of the time and customers to improve their transport and economic performance.The article shows that one of the ways to improve this type aircraft efficiency is the formation of their mass characteristics (i.e., mass of the aircraft modification itself and its individual units), which significantly affect all flight technical and economic parameters.It is proposed to take into account possible changes in four groups of parameters when assessing the starting mass (formed at the initial stages of creating a modification):T - a group of parameters that determine the level of requirements for a new modification;U - a group of parameters that determine the achievement of the stated goals at the stages of creation and operation of the modification;O - a group of parameters that determine the appearance of the future modification;P - a group of parameters that determine the mass and its density in the created modification.Division of the parameters into four groups makes it possible to evaluate and minimize the effect of the objective "square - cube" law on the mass gain in the design, production of a prototype and its flight tests and to represent it in the form of the starting mass of the modification (m0).The effectiveness of using the proposed approach to the formation of mass characteristics is shown on examples of the development of modifications of the An-124-100M and An-124-100M-150 airplanes.A distinctive feature of these modifications are: they were developed twenty years after creation of the base An-124 aircraft, carrying capacity has been increased by 30 tons, takeoff weight has been increased by 7%, the wing area, as well as the takeoff roll and landing run remained unchanged. The empty aircraft mass also remained unchanged, which indicates a special approach to the formation of mass characteristics. At the same time, in these modifications, the carrying capacity and flight performance increased by 25%, which is the highest achievement in the practice of creating aircraft of this type

Study of the Influence of the Beam-Column Line Stiffness Ratio on the Frame Structure Load Capacity Based on MATLAB

2011 ◽  
Vol 71-78 ◽  
pp. 4194-4198
Author(s):  
Shao Qin Zhang ◽  
Hua Hu Cheng
Keyword(s):  
Engineering Design ◽  
Carrying Capacity ◽  
Calculated Result ◽  
Load Capacity ◽  
Frame Structure ◽  
Stiffness Ratio ◽  
Displacement Method ◽  
Structure Form ◽  
The Matrix ◽  
Internal Forces

Statically indeterminate frame, composed of beams and columns, is a widely used structure form in civil engineering. The frame carrying capacity under various actions is related to the absolute stiffness of frame components and relative beam-column line stiffness ratio. The matrix displacement method and programming based on MATLAB were employed in this study to calculate the internal forces and displacements of a 2-bay 2-story frame structure under the action of horizontal loads. The influence of the beam-column line stiffness ratio on the frame load capacity was discussed based on the calculated result. Furthermore some advises were provided about the reasonable beam-column line stiffness ratio for engineering design.

scholarly journals The stress-strain state of gondola mounting bracket of a transport aircraft

2020 ◽  
pp. 117-123
Author(s):  
Sergii Trubachev ◽  
Olga Alexeychuk
Keyword(s):  
Finite Element ◽  
Power Plant ◽  
Strain State ◽  
3D Model ◽  
Stress Strain ◽  
Transport Aircraft ◽  
Finite Element Grid ◽  
Stress Strain State ◽  
Heavy Loads

The bracket is used to attach the gondola, which is an important part of the aircraft power plant. The gondola is constantly subjected to heavy loads when starting the engine, in flight, takeoff and landing. Therefore, the strength of the brackets of its attachment is very important. The geometric 3D model was built in SOLIDWORKS and imported for further calculations in ANSYS. A grid of tetraidal elements was created by the program. Thanks to the obtained FE (finite element) grid, we make the calculation of the stress strain state. Comments are provided on changes in the geometric and mass parameters of the bracket, based on the results of calculations.

scholarly journals Analysis on the influence of sinusoidal wind on the structure of pumping unit based on dynamics of solid-fluid interaction

2021 ◽  
Vol 69 (5) ◽  
pp. 165
Author(s):  
Zheng Liang ◽  
Luo-ming Zhao ◽  
Li-qin Tan
Keyword(s):  
Wind Speed ◽  
Wind Field ◽  
Research Work ◽  
Scientific Basis ◽  
Wind Load ◽  
Load Range ◽  
Pumping Unit ◽  
Stress And Deformation ◽  
Fluid Interaction ◽  
Field Area

China National Petroleum Corporation Dingbian oilfield is located in the wind field area of the beam pumping unit affected by the wind load, occurred several pumping unit bracket bending, beam fracturing, horsehead off and horsehead drop and other serious accidents, endanger the equipment and personnel safety. However, there is little research on the influence of beam pumping unit under wind load. Based on the dynamics of solid-fluid interaction theory and the standard k- turbulence model, this paper calculated the polished rod load range of the pumping unit according to the actual working condition of Dingbian oilfield, and established the CYJ10-4.2-53 numerical model of wind field. Under the sinusoidal variable wind speed conditions, the stress and deformation of the beam loader with different sizes of wind load on the beam loader were compared to those of the different sorts. The stress and deformation of the two different types of pumping unit were compared under the wind load. The results show that under the influence of wind load, the rig of the pumping unit bracket has a serious bending deformation, and the safety risk of the front end of the horsehead along the wind load is deformed. When the wind speed reaches 24.48m/s, the horsehead and barcket’s offset is the largest to the top dead point by the wind load, The minimum impact is affected by the wind load at the bottom dead center, The maximum offset of the horsehead and the bracket reached 8.5 mm and 2.16 mm. The research work of this paper provides a scientific basis for the improvement of safety structure for pumping unit in the wind field area.

scholarly journals Особенности деформаций главных балок железобетонных пролетных строений автодорожных мостов при их усилении внешней арматурой

2020 ◽  
Vol 44 (3) ◽  
pp. 151-158
Author(s):  
S. Tomilov
Keyword(s):  
Carrying Capacity ◽  
Load Capacity ◽  
Reinforced Concrete Beams ◽  
Main Beam ◽  
Relative Deformation ◽  
Operational Parameters ◽  
The Road ◽  
External Reinforcement ◽  
Bridge Structures ◽  
High Degree

Так как в настоящее время в эксплуатации находится достаточно много автодорожных мостов, запроектированных и построенных в различные периоды, их, как и всю дорожную сеть, необходимо поддерживать в состоянии, соответствующем нормативам, а для этого проводить ремонт с использованием элементов усиления несущих конструкций. При качественном возведении и надлежащем уходе высокая степень сохранности мостов позволяет продлить срок их службы путем решения ряда конструктивных вопросов, наиболее актуальным из которых считают обеспечение нормативной грузоподъемности. Усиление с целью повышения грузоподъемности эксплуатируемых мостов достигается путем добавления элементов внешних или внедренных в состав существующего конструктива в зависимости от типа сооружения, его состояния и доступной технологии производства. Однако не только грузоподъемность, но и подверженность конструкций деформациям определяет транспортно-эксплуатационные параметры сооружения, характеризующие послеремонтное состояния моста. Цель настоящего исследования – анализ известного и широко востребованного способа усиления железобетонных балок внешним армированием как обеспечивающего минимальное вмешательство в существующие основные конструкции, технологичного и доступного в исполнении. Впервые дана оценка влияния стадийности включения в работу элементов усиления на общие деформации – прогибы главных балок. Ключевые слова: главная балка, грузоподъемность, усиление, внешняя арматура, свободная затяжка, стадийность работы, относительная деформация, прогиб. Currently, there are quite a lot of road bridges in operation, designed and built in different periods. It is necessary to maintain the road network including bridge structures in a condition that meets up-to-date standards, and for this repair should be carried out using reinforcing elements of the supporting structures. With high-quality construction and proper maintenance, a high degree of safety of bridges allows to extend their service life by solving a number of design issues, the most important of which is considered to be the provision of standard load capacity. Strengthening in order to increase the carrying capacity of operated bridges is achieved by adding elements external or incorporated into the existing structure, depending on the type of structure, its condition and available production technology. However, not only the carrying capacity, but also the susceptibility of structures to deformations determines the transport and operational parameters of the structure, which characterize the post-repair state of the bridge. The purpose of this study is to analyze the well-known and widely demanded method of reinforcing reinforced concrete beams with external reinforcement as providing minimal interference with the existing basic structures, technological and affordable in execution. For the first time, an assessment of the influence of the staging of the inclusion of reinforcement elements in the work on the general deformations – deflections of the main beams. Keywords: main beam, carrying capacity, reinforcement, external reinforcement, free rod, staging of work, relative deformation, deflection.

Thermohydrodynamic Modeling of a Tapered-Land Thrust Bearing With Validation Against Experimental Data

2021 ◽  
Author(s):  
Seckin Gokaltun
Keyword(s):  
Heat Transfer ◽  
Transfer Problem ◽  
Load Capacity ◽  
Solid Surfaces ◽  
Fluid Film ◽  
Transfer Model ◽  
Analysis Model ◽  
Load Range ◽  
Benchmark Data ◽  
Computational Fluid Dynamics Cfd

Abstract In this work, a computational fluid-film bearing analysis model has been utilized in order to investigate the conjugate heat transfer problem for a tapered-land bearing using computational fluid dynamics (CFD) analysis. The academic model is based on the 2D Reynolds equation for the pressure distribution in the film the 3D energy equation is solved for the the bearing pad and the fluid film; therefore, the lubricant properties such as viscosity and density could be made temperature-dependent. The runner is modeled using a 2D axisymmetric mesh. The current analysis excludes the mechanical or thermal deformations of the bearing and the runner since it was observed that the results for output quantities such as film temperature, film pressure, torque and load capacity were within reasonable agreement with the benchmark data obtained from the experiments for the majority of the speed and load cases studied. Comparisons of modeling results against the benchmark data was obtained for cases ranging from 2000 rpm to 10,000 rpm at loads varying from 1000 N to 8000 N. The importance of proper boundary conditions used in the heat transfer model is emphasized as well as the coupling of heat transfer between the film and the solid surfaces of collar and the bearing is described. The results obtained here yielded that a thermohydrodynamic (THD) model that includes the energy transfer into the structures surrounding the fluid film is sufficient enough to predict the performance of a tapered-land bearing at a wide speed and load range in the case where the runner is thick enough that the effect of deformations on the results can be ignored.

Influence of geometric parameters on the bump foil bearing performance

2019 ◽  
Vol 234 (7) ◽  
pp. 1017-1026
Author(s):  
Sadanand Kulkarni ◽  
Soumendu Jana
Keyword(s):  
Carrying Capacity ◽  
High Speed ◽  
System Development ◽  
Load Capacity ◽  
Radial Clearance ◽  
Load Carrying Capacity ◽  
Foil Bearings ◽  
Foil Bearing ◽  
Load Carrying ◽  
Lift Off

High-speed rotating system development has drawn considerable attention of the researchers, in the recent past. Foil bearings are one of the major contenders for such applications, particularly for high speed and low load rotating systems. In foil bearings, process fluid or air is used as the working medium and no additional lubricant is required. It is known from the published literature that the load capacity of foil bearings depend on the operating speed, viscosity of the medium, clearance, and stiffness of the foil apart from the geometric dimensions of the bearing. In case of foil bearing with given dimensions, clearance governs the magnitude of pressure developed, whereas stiffness dictates the change in radial clearance under the generated pressure. This article deals with the effect of stiffness, clearance, and its interaction on the bump foil bearings load-carrying capacity. For this study, four sets of foil bearings of the same geometry with two levels of stiffness and clearance values are fabricated. Experiments are carried out following two factor-two level factorial design approach under constant load and in each case, the lift-off speed is measured. The experimental output is analyzed using statistical techniques to evaluate the influence of parameters under consideration. The results indicate that clearance has the maximum influence on the lift-off speed/ load-carrying capacity, followed by interaction effect and stiffness. A regression model is developed based on the experimental values and model is validated using error analysis technique.

scholarly journals A statistical method for predicting the eccentric load capacity of rectangular concrete filled steel tubular columns

2020 ◽  
Vol 313 ◽  
pp. 00031
Author(s):  
Glib Vatulia ◽  
Maryna Rezunenko ◽  
Dmytro Petrenko ◽  
Yevhen Balaka ◽  
Yevhen Orel
Keyword(s):  
Carrying Capacity ◽  
Load Capacity ◽  
Experimental Studies ◽  
Integrated Approach ◽  
Steel Shell ◽  
Eccentric Load ◽  
Concrete Core ◽  
Eccentric Compression ◽  
The Impact ◽  
Longitudinal Strains

The article deals with the integrated approach to the study of the behaviour of rectangular CFST columns under eccentric compression. Such an approach includes the development of methods for assessing the magnitude of the carrying capacity, assessing the degree of reliability and credibility of the obtained results, as well as studying the nature of the development of columns deformations at various stages of loading. The authors developed a mathematical model for calculation of columns carrying capacity under eccentric compression based on statistical methods. Substantial amount of experimental data collected by the world leading laboratories enabled obtaining a regression dependence of the columns carrying capacity that takes into account the impact of the physical and geometric characteristics of such structures. High degree of model confidence is confirmed by a comparative analysis with experimental results that are not involved in the development of the model, as well as with calculations performed according to Eurocode, Japanese and Chinese regulatory documents. The article presents experimental studies of the nature of deformations development on the surface of the steel shell and inside the concrete core of various lengths rectangular columns. As a result of the experimental tests, it was established that the longitudinal strains of the compressed area of the shell have the most significant impact on the bearing capacity of eccentrically compressed steel concrete samples.

Static characteristics of misaligned multiple axial groove water-lubricated bearing in the turbulent regime

2016 ◽  
Vol 231 (3) ◽  
pp. 385-398 ◽  
Author(s):  
Ravindra Mallya ◽  
Satish B Shenoy ◽  
Raghuvir Pai
Keyword(s):  
Reynolds Number ◽  
Friction Coefficient ◽  
Carrying Capacity ◽  
Journal Bearing ◽  
Load Capacity ◽  
Turbulent Regime ◽  
Load Carrying Capacity ◽  
Static Characteristics ◽  
Load Carrying ◽  
Turbulence Effects

The static characteristics of misaligned three-axial water-lubricated journal bearing in the turbulent regime are analyzed for groove angles 36° and 18°. Ng and Pan’s turbulence model is applied to study the turbulence effects in the journal bearing. The static parameters such as load-carrying capacity, friction coefficient, and side leakage are found for different degree of misalignment (DM). The change in flow regime of the lubricant from laminar to turbulent and the increase in misalignment, improved the load capacity of the bearing. For lightly loaded bearings, the friction coefficient of the bearing increased with the increase in Reynolds number.

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