Vol 13, No 5-3 (2014): Special Issue

Full Issue

Development of methods of modeling and computer aided design of gas turbine engines
Krivosheev I.A., Kozhinov D.G.
Abstract

Methods of computer-aided design and modeling of GTE are discussed. The results of development of a universal, open technology for simulation of sophisticated technical objects are described. The proposed technology allows solving simulation tasks for modeling the performance of aircraft engines as a part of an aircraft. Other technical objects successfully simulated using this technology, include power plants of various types. The experience of automated selection of construction layout of gas turbine engines is shown. Co-modeling of gas turbine engine and its automated control system is described. The research was conducted using domestic PLM and CAD/CAE systems, such as SPRAD, Stalker, and a number of other applications for technological design of parts and components of gas turbine engines. The effectiveness of combining the functionality of the multi-level simulation with the means of CAD/CAE/PLM systems is shown. Shown use DVIG at seminatural simulation TVVD (D-27) and its ACS. A method for obtaining the characteristics of compressors, using the developed simulation systems blade rows, steps, compressors and dvigateley.V including new approaches to the design of turbomachinery (tracking method jets - ISO). Shows the results of the development of LSI components for the organization Operation Support GTD to-date. In particular, it is described developed IETM (Interactive Electronic Technical Manual) Operating GTR (gas turbine drive) AL-31ST used in Gazprom at compressor stations.

VESTNIK of Samara University. Aerospace and Mechanical Engineering. 2014;13(5-3):9-18
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Development of a technique of molding small complex parts of gas turbine engines from high-temperature alloys using additive technologies
Smelov V.G., Balyakin A.V., Agapovichev A.V., Vdovin R.A.
Abstract

Rapid prototyping technologies provide a unique opportunity to receive cost-effective solutions for the production of parts by investment casting. Research and development of rapid prototyping technologies allowed to move to a next level of optimization and the introduction of new processes in various areas of industry. At the stage of pilot production, which is characterized by frequent changes in design, the problem of the rapid production of cast components becomes crucial. This is mainly due to the complexity and the complexity of manufacturing foundry equipment. In turn, the research and development of rapid prototyping technologies have allowed a new level of optimization and the introduction of new technologies in the investment casting. The aim of this work is to identify opportunities and evaluate accuracy of the size of the casting during investment casting using rapid prototyping technology. The work was conducted with the use of cross-cutting design in CAM/CAD/CAE systems. The study size and precision parameters of the casting was conducted in coordinate measuring machine. The work has been verified the adequacy of the virtual simulation of the process of forming a casting in the casting simulation ProCAST, in comparison with those obtained castings. The study showed that the use of rapid prototyping technologies with investment casting can significantly reduce the time for making castings, reduce production costs and improve the accuracy of the size of the casting.

VESTNIK of Samara University. Aerospace and Mechanical Engineering. 2014;13(5-3):19-25
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Analysis of the results of thermal cycic tests using TC-maps and problems of investigating thermal fatigue of materials
Tikhomirova E.A., Sidokhin E.F.
Abstract

We present a method for the analysis of the progress of the deformation within a cycle by constructing the diagram TC-maps, where presented dependences of the temperature – free thermal deformation – elastic deformation, corresponding to the flow limit of the material. The diagram shows the magnitude of the plastic deformation attained at the maximal temperature (Tmax) and its changes in the cycles. The diagram allows permits one to choose the temperature mode required to obtain the desired deformation parameters in a test. An application of the diagram is presented in the case study analyzing the method and results of thermocyclic tests conducted on the high-heat resistant alloy used for the construction of the blades in the VNKNA-1V turbines. It has been concluded that under all possible modes the material is subject to plastic deformation within a cycle. Its presence does not allow one to conclude the dependence of the lifetime from the magnitude of the maximal stress registered within a cycle.

VESTNIK of Samara University. Aerospace and Mechanical Engineering. 2014;13(5-3):26-34
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Results of experimental studies of parameters of low-thrust rocket engines operating on gaseous oxygen-hydrogen fuel
Ageenko Y.I., Lapshin E.A., Morozov I.I., Pegin I.V., Ryzhkov V.V.
Abstract

The article presents the results of an experimental study of the thermal parameters and with-standing experimental samples rocket engines gaseous oxygen with thrust 25 N and 100 N. In experimental models rocket engines thrust 25 N and 100 N ignition fuel components arranged in the discharge chamber spark plugs. Scheme carburetion of engines characterized by the interaction of coaxial swirling flows of fuel and oxidant is carried out in two stages. At the same time, realized highly turbulent flow, contributing to the efficient mixing of fuel and oxidizer in a limited volume of the combustion chamber. Cooling chamber traction motor 25 H organized using a gas curtain of fuel from the mixing head and the application of high temperature structural material – boronsiliconized graphite, which is made of a combustion chamber and a nozzle. In rocket engines thrust 100N further organized subsonic curtain fuel located at the end of the cylindrical portion of the combustion chamber, but at the same time as the construction material used stainless steel type 12X18H10T. Experimental studies have been tested two structural variants of organization of the ignition process, evaluated the effectiveness of the scheme of mixing hydrogen and oxygen gases. In this case, the following values of specific impulse engines: for rocket engines thrust 25H with the geometric expansion ratio of the nozzle Fа = 45 - 3846 m/s; for rocket engines thrust 100N with Fа = 45 and Fа = 250 – respectively 3855 m/s and 4100 m/s. From the point of view of the thermal state in the study design rocket engines propellants, promising is the use of new construction materials, such as ceramics, graphite-based materials with the development of the technology for their production, as well as interfacing to the mixing head, made, usually made of stainless steel. In support of the above, in the use of the camera rocket engines thrust of 25N boron-siliconized graphite allowed during the test the engine for 100 seconds to get the maximum temperature of the outer surface of the chamber at ~ 1045 ° C.

VESTNIK of Samara University. Aerospace and Mechanical Engineering. 2014;13(5-3):35-45
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Verification of energy efficiency of a low-thrust liquid-propellant engine with the deflector-centrifugal injecting pattern
Ageenko Y.I., Pegin I.V.
Abstract

The article gives information about developed in Design Bureau Chemical Machinery behalf A.M. Isaev deflector centrifugal pattern mixing of propellants nitrogen tetroxide and unsymmetrical dimethylhydrazine, in which established liquid rocket engines (LREST) in a wide range of rods from 25 to 400 N. Design Bureau Chemical Machinery behalf A.M. Isaev on the basis of joint with KUAI (now SSAU named after Korolev, Samara) and studies on the characterization of the primary oxidant film on the deflector, the parameters of the secondary oxidant film on the inner wall of the combustion chamber, the parameters of the film cone spray nozzle centrifugal fuel in a venue with a secondary film oxidant parameters of the layer of liquid-phase mixing the oxidizer and fuel components on the inner wall of the combustion chamber was established mathematical model calculations of liquid-phase mixing of the components in the mixing element LREST with centrifugal deflection circuit mixing the components on the wall of the combustion chamber. Based on this Design Bureau Chemical Machinery behalf A.M. Isaev developed technique of calculations and design of LREST with centrifugal deflection circuit mixing fuel. Using this method in Design Bureau Chemical Machinery behalf A.M. Isaev designed iPart LREST 25, 50, 100, 200, 400N, with deflector centrifugal mixing scheme. Parametric studies were conducted LREST of 25, 50, 100, 200, 400 N to determine the degree of influence of various design and operational parameters of the element, such as the angle of leakage jets on the deflector angle leakage of primary films on the wall of the combustion chamber, the mean free path of the secondary oxidant film the wall of the chamber performance-liquid phase mixing of the fuel components. The results of experimental studies have confirmed the increased energy efficiency of small thrust jet engine thrust of 25, 50, 100, 200, 400 N with deflection centrifugal mixing scheme, expressed in a high specific impulse of more than 3000 m / s at the same time a large margin the temperature of engine components. Maximum temperature of the wall of the combustion chamber is at 1200 °С that is provided by a large margin – 600 °С (permissible material temperature chamber - niobium alloy with molybdenum coating bi-silicified MoSi2 – 1800 °С).

VESTNIK of Samara University. Aerospace and Mechanical Engineering. 2014;13(5-3):46-54
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Investigation of the vibration behavior of a gas turbine engine in icing conditions
Danilkin S.Y., Teleshev V.A.
Abstract

With respect to aeronautical engineering it is focused on the problems of the dynamic strength of parts and units of aircraft engines, namely the resistance of the material under the action of various oscillatory processes (vibration) arising from the operation of such engines. An important aspect of this problem is to ensure the safety of flight in atmospheric icing conditions. Relevance of study is determined, above all, the lack of study of the processes of icing. The paper summarizes the results of processing the experimental data obtained in a test of gas turbine engines in icing conditions at a specialized ground test rig. The stages of the process with regard to icing vibration condition of the engine. In the course of experiments on icing were found in the spectrum of the vibration diagnostic signs of the blades self-oscillations. One of the probable causes of such hazardous processes may be throttling the fan due to ice build-up on the blades straightener or on input parts of the fan. However, for a more detailed description of these phenomena occurring in icing conditions, additional studies, experiments, calculations. This article describes the features of the study of vibrating processes in the engine in such trials. It is discussed the directions for further research on this issue.

VESTNIK of Samara University. Aerospace and Mechanical Engineering. 2014;13(5-3):55-59
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Numerical simulation of tonal noise of a bypass engine fan stage
Pyatunin K.R., Arharova N.V., Remizov A.E.
Abstract

With the tightening of the norms of ICAO aircraft noise on the ground is necessary to pay more attention to the acoustic design of power plants. For modern civil aircraft engines with high bypass fan is characterized by a dominant influence on the overall noise level. Due to the fact that the design of the fan and LPC largely determines the design of the engine must still at the project stage to be able to assess the acoustic characteristics of this module. This provides an opportunity to use methods of computational aeroacoustics. The results of numerical simulation of fan tonal noise using commercial code were presented. The results of calculations include the sound pressure level and sound radiation directivity for approach. The simulation was carried out for full nonaxisymmetric case. The possibility of using this method for evaluation of acoustic characteristics aircraft engines fan are analyzed.

VESTNIK of Samara University. Aerospace and Mechanical Engineering. 2014;13(5-3):60-65
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Deformation and fracture strength of single-crystal superalloys under static and cyclic loading
Semenov A.S., Getsov L.B., Semenov S.G., Grishchenko A.I.
Abstract

The peculiarities of short-term resistance to tension/compression, creep, long-term strength and thermal fatigue of single-crystal superalloys for different crystallographic orientations and temperatures are considered. The failure criteria are proposed using a unified measures equivalent stress (strain) for the cubic system, allowing to compute adequate strength and durability of single crystal materials under complex multi-axial inhomogeneous stress state, which is characteristic for gas turbine engine blades during the operation.

VESTNIK of Samara University. Aerospace and Mechanical Engineering. 2014;13(5-3):66-75
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Influence of vibration conectedness on eigenmode shapes of bladed disks with non-identical blades
Ermakov A.I., Urlapkin A.V., Fedorchenko D.G.
Abstract

The paper discusses the vibrations of bladed disks with non-identical blades. Eigenvalues of this disks due to violation of rotational symmetry is always the case of the harmonic distortion of the distribution of the displacement along the circumference (the eigenvalues distortion). It has been established that the magnitude of distortion, and hence the degree of disruption of rotational symmetry of a wheel depends not only on how much different vanes from one another, but also from connection oscillations. By the calculation and experimental way it is studied distortion of eigenvaluesof bladed disks in violation of rotational symmetry with decreasing vibration connectedness up (by increasing the thickness of the disk) to its complete disappearance on an example of a model bladed disk.Introduced a coefficient of quantitatively assessing the value of the degree of violation of rotational symmetry. As an example of mode shapes represented by the bladed disks of the NK-12 compressor. A decrease in the vibration connectedness leads to a distortion in the beginning of the distribution of the harmonic offsets, and then to localize forms. It was noted that localized forms are not self-equilibrated and may lead to excitation of oscillations of the rotor.

VESTNIK of Samara University. Aerospace and Mechanical Engineering. 2014;13(5-3):76-81
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Significance and directions of development of rotary piston area of research
Okorochkov V.V., Okorochkova V.M., Shafranov V.V.
Abstract

The development of small and unmanned aircraft in Russia is hampered by the lack of production of domestic aircraft engines in the power range up to 200 h.p. The main requirement for the aircraft engine is minimal ratio of mass and overall dimensions to output. In a greater degree that is matched by the engines of rotor piston layout. The intensive work on rotor piston engines is carried out abroad by companies of many countries: Britain (UAV), USA (Freedom Motors), Austria (Austro engine) etc. In Russia, at SKBM the works on rotor piston engines were conducted for outboard motor application in cooperation with Rotor Piston Engines Design Bureau of AVTOVAZ. For the satisfaction of needs for small and unmanned aircraft a project of creation of rotor piston engines in the power range of 8-200 h.p. was developed.

VESTNIK of Samara University. Aerospace and Mechanical Engineering. 2014;13(5-3):82-91
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Development of methods of carrying out experimental research of measurement errors for sets of geometrical parameters on NC equipment as in the case of a turbine disk
Bolotov M.A., Alexeev V.P., Pronichev N.D.
Abstract

The technique of experimental studies of measurement error groups of geometrical parameters on CNC equipment on example radial-angular positions of turbine disk is developed. This technique consists of a series of successive stages: analysis of parts and groups of geometric parameters; calibration of the measurement system; binding to the details; selection of the measurement cycle; development of the control program to be measured; measurements on CNC equipment and KIM; comparison of measurement results; error analysis, the establishment of their causes and the proposal to reduce them. For the analysis of obtained results is used a statistical method for determining the total error. The random component was evaluated by multiple repetition of the process of measuring the centering holes on CNC equipment and statistical processing of the results. The systematic error was estimated by comparing the data obtained as a result of control on CNC equipment with reference values. As reference data taken measurements on coordinate-measuring machine Global Performance 07.10.07. Control radial-angular arrangement centering holes turbine disk is possible using standard measuring cycle equipment. It is worth noting the dependence of the accuracy of measurement of the nominal angle of the dowel holes. With the increase in the angle measurement error increases. This technique is universally applicable to the measurement of many geometric parameters of the different parts.

VESTNIK of Samara University. Aerospace and Mechanical Engineering. 2014;13(5-3):92-99
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Study of the structure of spherical roller surfaces in grinding
Nosov N.V., Mikhailova L.N.
Abstract

The methods of grinding the spherical ends of tapered rollers using the wheel end and periphery are considered. The ways of improving the accuracy of the spherical end when processing using the periphery of a grinding wheel, radially refilled, and ensuring the surface quality due to uneven wear of a wheel are shown. It has been established that increasing the efficiency of grinding the spherical surfaces of a roller is carried out by reducing random and systematic error components of processing. The results of grinding using the corrected radius and the processing device for continuous grinding of spherical roller ends are represented. The structure of surfaces of spherical roller ends using the optical-electronic complex that could reduce the influence of the cur vature of the surface under study on its image is investigated. An algorithm of using binarization of an original halftone image for analyzing the structure of the treated surface, which provides processing and output of the results on the PC screen is considered. The binary images of the surface structure of spherical roller ends with different roughness are shown. The studies of the effect of the average amplitude of oscillation of the autocorrelation function depending on the surface roughness are performed. Thus, the relationship of roughness of the surface profile with the parameters of the autocorrelation function is shown. The optimum parameters of the surface structure, the amplitude of the autocorrelation function and the mathematical expectation that will provide an increase in performance properties of the contact surfaces are determined.

VESTNIK of Samara University. Aerospace and Mechanical Engineering. 2014;13(5-3):100-105
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Research of machinability of heat resistant steels 10Х11НN23T3MР-ВД used in parts of gas turbine engines
Surkov O.S., Kondratiev A.I., Alexeev V.P., Haymovich A.I.
Abstract

In article questions the workability of heat-resistant chromium-nickel steel 10Х11Н23Т3МР-ВД are considered. To investigate the machinability of heat-resistant material used modern milling machines, CNC torque table Kistler, modern monolithic milling tool company Seco, in the form of the mandrel used termic clamping provides the highest rigidity fixing. Posed a series of experiments to measure the cutting forces that arise during processing. For the experiment were selected workpiece in the form of plates. The surface of each sample is pretreated so that the initial surface roughness for all samples was the same Ra 1,25. Materials blanks: Steel ЭП33 ВД (10Х11Н23Т3МР-ВД). As a cutting tool in the model used milling company Seco. The analysis and processing of the experimental results are provided. According to experimental data are constructed dependences of the cutting force on the speed, depth of cut and feed. Depending obtained using neural network models, linking cutting forces with the technological parameters.It is established that the neural network model provides a more accurate prediction of cutting forces, especially in the field of higher cutting speeds. Since the full-scale testing was costly for the purchase of an experienced tool and workpiece, the cutting process was modeled with the given experimental conditions for comparison of experimental data and modeling. For this purpose, it was used a virtual simulation of the machining in the environment DEFORM 3D.

VESTNIK of Samara University. Aerospace and Mechanical Engineering. 2014;13(5-3):106-112
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Computer-aided system of virtual gas turbine engine testing
Tkachenko A.Y., Rybakov V.N., Krupenich I.N., Ostapuk Y.A., Filinov E.P.
Abstract

The article describes the concept of a virtual lab that includes subsystem of gas turbine engine simulation, subsystem of experiment planning, subsystem of measurement errors simulation, subsystem of simulator identification and others. The basis for virtual lab development is the computer-aided system of thermogasdynamic research and analysis “ASTRA”. The features of gas turbine engine transient modes simulator are described. The principal difference between the simulators of transient and stationary modes of gas turbine engines is that the energy balance of the compressor and turbine becomes not applicable. The computer-aided system of virtual gas turbine engine testing was created using the developed transient modes simulator. This system solves the tasks of operational (throttling, speed, climatic, altitude) characteristics calculation, analysis of transient dynamics and selection of optimal control laws. Besides, the system of virtual gas turbine engine testing is a clear demonstration of gas turbine engine working process and the regularities of engine elements collaboration. The interface of the system of virtual gas turbine engine testing is described in the article and some screenshots of the interface elements are provided. The developed system of virtual gas turbine engine testing provides means for reducing the laboriousness of gas turbine engines testing. Besides, the implementation of this system in the learning process allows the diversification of lab works and therefore improve the quality of training.

VESTNIK of Samara University. Aerospace and Mechanical Engineering. 2014;13(5-3):113-119
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Criterion of optimization of slow fatigue crack growth in metals and alloys
Kol’tsoun Y.I., Molyavko D.P., Ignatovskiy A.D., Khibnik T.A.
Abstract

Based on macro structural analysis of a typical fatigue fracture of a cylindrical specimen of alloy D16T with an annular notch in bending is shown the technique of constructing the kinetic diagram of slow growth of fatigue cracks in the light of the third coordinate - the number of cycles. It is shown the quantification of growth up cracks in the projection plane: of quantity of cycles - the speed of the crack. A kinematic diagram of slow growth of a fatigue crack gives the possibility to assess the beginning of intensive increase to a stable crack growth of 10-6 – 10-4 mm/cycle. It is technically difficult to monitor fatigue crack growth at this level of growth rate. This is why the beginning stage of the transition from a slow-growing fatigue crack to a stably growing crack is an important technological safety parameter in the operation of parts with cracks. This work proposes a new criterion of assessing the optimality of slow fatigue crack growth on the example of the aluminum alloy D16T.

VESTNIK of Samara University. Aerospace and Mechanical Engineering. 2014;13(5-3):120-125
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Forecasting an increment in the parts’ endurance limit due to surface hardening
Pavlov V.F., Filatov A.P., Semyonova O.Y., Sazanov V.V., Mikushev N.N.
Abstract

Rolling with various forces influence on the endurance limit of specimens made of steel 20 of 50 mm diameter with cuts of various radiuses and pressurized bush has been examined. The estimation of the surface hardening influence on the specimens endurance limit has been carried out using two criterions, namely: residual stresses on the dangerous section surface and the average integral residual stresses through the dangerous section thickness, equal the fatigue non-propagating crack critical depth. On base of carried out experiments it’s been established that the employment of the average integral residual stresses criterion is more rightful for the endurance limit prediction of surface hardened cylindrical specimens made of steel 20 with diameter 50 mm with cuts and pressurized bush taking into account the concentration degree. The residual stresses on the concentrator surface is not acceptable as a criterion for the endurance limit prediction of surface hardened specimens made of steel 20 with cuts and pressurized bush because the corresponding coefficient of the criterion influence on the endurance limit has a essential dispersion. Besides, the dependence of the fatigue non-propagating crack critical depth on the specimen (part) dangerous cross-section sizes has been confirmed.

VESTNIK of Samara University. Aerospace and Mechanical Engineering. 2014;13(5-3):126-133
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Dynamic of the a safety vent valve
Makaryjants M.V., Kudyurov L.V., Mustafaev Y.K., Tumanov D.V.
Abstract

The mathematical model that simulates the running of drainage safety valve is concerned. The valve controls pressure through the sensor. The movement is discussed taking into account the following aspects: alterations of pneumatic capacities specified in device design, alterations of the pressure in pneumatic volumes at the permanent temperature, there is gas overflow occurring in special channels between specified volumes, there is the friction between the valve plate and its sliding rail, there are periodical external dithers of a variable frequency. The results of computational modeling and cause analysis of maintained pressure depreciation by the specified frequencies are provided.

VESTNIK of Samara University. Aerospace and Mechanical Engineering. 2014;13(5-3):134-141
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Technological processes of producing materials by specified criteria of forming the properties of aircraft assembly units
Tlustenko S.F.
Abstract

Results of formation of structure of an assortment from the technical cleanliness titan depending on coarse-grained or nanostructural state for maintenance of mechanical properties received by various ways of details of assemblages are presented. The structure of the titan depending on conditions and character saturation by hydrogen is studied at machining. It is established that modes on character of technological deformation of preparations render proskating rinks of strips and sheets hereditary influence on fluctuations of mechanical properties of metal on its area and a thickness. It is shown the results of studies link changes in crystallographic texture samples of titanium with the nature of the formation of the microstructure of the alloy in the technological processes of hot plastic deformation on the example of cylindrical samples of two-phase titanium alloy VT9 under various schemes application of stress and strain in machining, tension, torsion, ching.

VESTNIK of Samara University. Aerospace and Mechanical Engineering. 2014;13(5-3):142-147
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3D-kinetic characteristics of slow fatigue crack growth in the aluminum alloy D16T
Kol’tsoun Y.I., Molyavko D.P., Ignatovskiy A.D., Khibnik T.A.
Abstract

It is presented the technique based on macro structural analysis of a typical fatigue fracture of a cylindrical specimen of alloy D16T with an annular notch in bending of constructing the diagram of stress intensity coefficient defined the period growth of fatigue crack. Analytical calculation of the change in the exponent m in Peris’ formula for calculating the speed of fatigue crack growth with respect to depth a in a system with consideration of the increase in the number of cycles N of high-cycle fatigue has be established using experimental data of fatigue fractures of the aluminum alloy D16T. This made it possible to draw the kinematic diagram of a slow fatigue crack growth of D16T in a 3-dimensional coordinate system. Analyzed and numerically determine volumes are formed with the space curve the kinetic diagram of a slow fatigue crack growth. Installed a new kinetic characteristic of fatigue crack growth; i.e. the amount of work of the stress intensity coefficient used to connect parameters of low-cycle fatigue and high-cycle fatigue.

VESTNIK of Samara University. Aerospace and Mechanical Engineering. 2014;13(5-3):148-157
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Automated profiling of tool electrode in electrochemical pulse machining
Nekhoroshev M.V., Pronichev N.D., Smirnov G.V.
Abstract

Compressor blades are the most complex and critical parts of a gas turbine engine. It is driven by the cost of their production, as well as the requirements in terms of reliability and service life. A promising method for manufacturing the blades is a pulse electrochemical machining (ECM), the main advantages of which are the lack of power and thermal effects on the treated surface, the longevity of the tool, at low values of roughness parameters when working at high current densities in high-precision copy form and stability during operation of the process at a sufficiently small interelectrode gaps. In this paper we have set out the principles for the implementation of the model applied to the electrochemical shaping pulse echo that will deliver engineering simulation methodology for processing and profiling tool electrode in a real production. In solving the problem of electrochemical formation, taking into account the factors influencing the process was proposed algorithm describing the process of pulse echo, which was based on the use of a numerical method for sample processing in time and space. This algorithm will automate profiling tool electrode during pulse electrochemical treatment.

VESTNIK of Samara University. Aerospace and Mechanical Engineering. 2014;13(5-3):158-166
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Results of hot tests of an oxygen preburner of a liquid-propellant engine 11D58MF
Barsukov O.A., Strizhenko P.P.
Abstract

In this article results of LRE 11D58MF oxygen preburner development are considered. Preburner consist of two zones. In the first zone fuel is burned, in the second zone combustion products are mixed with the rest of oxygen. There were 39 hot test on five preburners performed. Tests were conducted with variable chamber pressure, propellant mixture and initial temperature of gas oxygen. Evaluation of temperature field distribution and uniformity in outer section was performed. Mean temperature of combustion products on the exit section of preburner, obtained from test results, agreed well with theoretical calculations. Operational stability of preburner with various input parameters is confirmed. Design of injection elements and fuel input chamber were improved on order to assure reliability of preburner. Ignition and stop sequence instructions were formulated. There’s need to test three more preburners to complete individual development test series.

VESTNIK of Samara University. Aerospace and Mechanical Engineering. 2014;13(5-3):167-175
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Estimation of mass-dimensional characteristics of a complex propulsion unit of earth remote sensing spacecraft
Kurenkov V.I., Kucherov A.S., Yakishik A.A.
Abstract

An estimation method for weight and size characteristics of complex propulsion unit (CPS) of the Earth remote observation spacecraft determination based on calculations of required characteristic velocity needed to carry out various kinds of maneuvering is proposed. Program complex for automated posing and solving of design problems by choosing the design characteristics of CPS is developed based on a problem-oriented programming and implementing the exact approximation concept. Within the concept, optimization of CPS basic design parameters is carried out in implicit form, without setting the mathematical programming problem, which requires formulation of objective functions and limitations. Software package developed in the programming language Java is described. Use of the package is illustrated by determination of CPS parameters needed to provide given characteristic velocity for the spacecraft with given mass. In order to perform quick comparative analysis of alternative design versions of CPS, the package provides import of calculated design parameters into 3D design system wherein original parameterized CPS model may be preliminarily constructed.

VESTNIK of Samara University. Aerospace and Mechanical Engineering. 2014;13(5-3):176-185
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Development of parameter-orientedmodels of bladed disks for static strength analysis
Shklovets A.O., Urlapkin A.V., Boyarov K.V.
Abstract

In today's competitive production is important shortening time-processing products, which can be achieved using modern digital technology. Work is devoted in creating parametric finite element models of the compressor and the low-pressure turbine rotor wheels and a free turbine of modernized gas compressor unit NK-36ST using the package ANSYS Mechanical. The developed models of blades and disks allow to control grid of finite elements and the geometrical parameters of the structure in a wide range: the geometry of the blade, shapes and sizes for radius transition, shank geometry, dimensions of structural elements of the disc. The geometry of the airfoil blades is read from the file received as a result of gas-dynamic calculations. Models rotor wheels consider contacting a locking connection. Approach to the creation of the finite element mesh is to use structured and hybrid scheme that reduces the amount of grids and as a consequence, reduces the calculation time. The use of such models for the calculation of static strength under changing the geometric parameters of the gas-dynamic optimization when allowed to make them as soon as possible. With the help of the developed models in the future produced calibration calculations and confirmed reserves of strength.

VESTNIK of Samara University. Aerospace and Mechanical Engineering. 2014;13(5-3):186-191
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A new approach to teaching descriptive geometry at higher school from the perspective of through preparation of a modern specialist
Ermakov A.I., Chempinsky L.A.
Abstract

The adaptation to a new design and manufacture technologies of products is related with necessity for forming а new of thinking of professionals. A more research should be given to learning 3D modeling. A description of processes of educational activities is presented in the form of contextual diagrams IDEF0 – models for preparing specialists at the Faculty of aircraft engines SSAU, its decomposition by type of training. The goals of the Engineering graphics department, in addition to knowledge of the creation 3D modeling, are learning the basics of document management and methods of standard models’ parameterization and their using. At the same time a number of problems is being solving: a gradual (from the beginning) familiarization with capabilities and a consequent acquisition of skills in an environment of modern integrated CAD / CAM / CAPP systems; an optimal solution of descriptive geometry, in particular, using and development of spatial imagination, the exact solution of the metric and positional problems; achievement the new level of geometrical-graphic preparation by using parametric models for performing 3D details, automated construction the drawings on a plane with GOST rules ESKD, which significantly reduces the routine work in creating technical documentation for the following departments. Realization of this approach in training specialists allows to use a 3D model constructions for engineering analysis of their functioning in the conditions of use, as well as to model a manufacturing process in the virtual space.

VESTNIK of Samara University. Aerospace and Mechanical Engineering. 2014;13(5-3):192-201
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Improving the accuracy of assessing the position deviation in coordinate measurements of GTE compressor and turbine blade profiles
Bolotov M.A., Pechenin V.A., Ruzanov N.V.
Abstract

The paper proposes a method for increasing the accuracy of the iterative closest point (ICP) algorithm used in metrology problems in determining position deviation. The target of using the method for determining deviation profiles were compressor blades of a gas turbine engine (GTE). We propose to formulate the problem of the optimal match in the developed method as a multicriterion task including the criteria of the minimum of squared distances, differences of normal vectors and difference values of the depth of camber at the appropriate points of the superposed profiles. Different variants of reducing the problem to the use of a single integral criterion including the above-mentioned ones are considered. The problems of optimization were solved using the quasi-Newtonian methods of sequential quadratic programming. The proposed new method of improving the ICP algorithm based on geometric features showed greater accuracy in comparison with the discussed methods for optimizing the distance between the fitting points, especially in the case of a small number of measurement points on the profiles.

VESTNIK of Samara University. Aerospace and Mechanical Engineering. 2014;13(5-3):202-211
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Development of the technology of diagnostics of turbo-jet aviation engines by a filtering element with a diagnostic layer
Drokov V.V., Drokov V.G., Muryshenko V.V., Mukhutdinov F.I., Khaliullin V.F.
Abstract

The possibility to use the Dirt Alert diagnostic layer to diagnose PS-90A engines equipped with QA-07930-01 filter elements by Pall Corporation is shown. Division of Dirt Alert diagnostic layer into parts according to their height allows to get wash samples and to make diagnostics of PS-90A engine without disassembly and replacement of main filter element before completion of its mission. Device and ultrasound methodology of wear debris particles extraction from diagnostic layer are developed. It is determined that wash sample presentability is provided by single passage of diagnostic layer in tape drive during 20 minutes. The possibility to use a statistical model of operational PS-90A engine equipped with the filter element without diagnostic layer that had been previously developed basing on wash sample analysis in order to make a diagnostic decision on PS-90A engines equipped with QA-07930-01 filter element is considered. In this model, wear debris particles ratings are used as diagnostic parameters. It is shown that parameters of wash sample wear debris particles extracted from diagnostic layer of QA-07930-01 filter element do not differ from QA-07930 filter element wash sample particles parameters. It means that PS-90A engine equipped with QA-07930-01 filter element technical state evaluation is possible with use of the statistical model of operational PS-90A engine equipped with the filter element without diagnostic layer developed basing on scintillation analysis of wash sample taken from QA-07930 filter element. The conclusion is made that perspective direction to get express and reliable results of technical state evaluation for PS-90A engine lubrication system is to equip engines of this type with QA-07930-01-type filter element.

VESTNIK of Samara University. Aerospace and Mechanical Engineering. 2014;13(5-3):212-218
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