Mathematics. Physics. Mechanics |
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Krupenin A. M., Martirosov M. I.
Object: the object of the research is dynamic characteristics of the three-layer rectangular symmetric plate with isotropic filler.
Topic: the research of impact interaction of a three-layer rectangular symmetric plate with isotropic filler of liquid.
Aim: to examine the influence of various factors on the dynamic characteristics of a three-layer rectangular symmetric plate with isotropic filler at a vertical fall of the liquid.
Researchmethod: dynamic characteristics of a three-layer rectangular symmetric plate with isotropic fillerinvestigated numerically in the software complex ANSYS AUTODYN, thus permitting the equations are equations of conservation of energy, momentum and mass. The solution is explicitsolver. The task is placed in the axisymmetric formulation of coherent, i.e. equations for plates and liquid are solved simultaneously. The obtained results are processed in software complexMathCad 14.
Results: as a result of the work are obtained dynamic characteristics of a three-layer rectangular symmetric plate with isotropic filler when it hit the water with different initial velocity of interaction, taking into account the gravitational forces and without. The air gap between the plate and the liquid are not taken into account.
Conclusions: the influence of gravitational forces depends on the initial velocity of the body, and the geometry of the model. When increasing the initial speed of interaction of the influence of gravitation on the dynamic characteristics of rapidly decreasing. On the considered section of the velocities of the initial interaction dependence of displacements, velocities, accelerations and stresses on the initial velocity of uniform. Maximum stresses appear in the first carrier layer of about 50 mm from the center of the plate (~1/5 a). Stresses in the fillera ten times less stress in the carrier layers, which allows to use more light and less durable materials. Maximum stresses in the second carrier layer a half times less than the maximum stress in the first, that allows to make in the construction of asymmetry in thickness.
Keywords: impact, three-layered plate, interaction with liquid, numerical simulation |
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Axisymmetric (n = 0) and non-axisymmetric (n = 1,2,...) vibrations of compound elastic orthotropic shells of revolution with ring frames are considered (n is the number of sine or cosine waves in the circumferential direction). The preliminary axisymmetric stress-strain state of the shell is taken into account. The deformation model of the shell is based on the Kirchhoff-Love hypothesis. The dimensions of the frame cross sections are considered like small in comparison with their radii. The eccentricities of the frame connections with the shells are taken into account. The ring frames with arbitrary solid cross sections which are assumed non-deformable are considered as curvilinear rods undergoing to tension-compression, bending in the two planes and torsion. The thin-walled frames with the arbitrary open or closed deformable cross section contours are considered as shells of revolution.
The finite element method (FEM) is used to calculate vibrations of a compound axisymmetric structure. The finite elements (FE) of the shells and thin-walled frames are considered as narrow ring conical belts. In the limits of the belt width the meridional and circumferential displacements are approximated by two-term linear functions and the normal displacement is approximated by four-term cubic polynomial. The shell of revolution poles are replaced by the circular plates or orifices with sufficiently small radius.
The amplitude values of the axial, radial and circumferential displacements as well as meridional angles of rotation for n-th harmonic on the FE junction circles and on the ring reference circles are considered as generalized coordinates. The equations of vibrations of the system in generalized coordinates are obtained by the Lagrange method taking into account the junction conditions between the rings and FE as well as the fixation conditions. Afterwards for practical calculations the obtained equations are transformed to uncoupled equations in the normal coordinates which represent to the motions for the normal modes of the system.
The developed by FEM algorithm is sufficiently general and can be used for calculation of vibrations of compound systems of arbitrary orthotropic shells of revolution with variable along the meridian thickness and with different ring frames. All coefficients of rigidity and inertia matrices of the FE and rings are written in formulas.
As an example free axisymmetric vibrations of a cylindrical shell fixed at the upper and connected at the lower via an elastic ring with a spherical shell with an attached massive load are considered. Calculations of the mode frequencies are fulfilled for two variants of the connecting ring with the same area but different shape of the cross section.
Keywords: shell of revolution, compound shells, circular frame, thin-walled frame, elastic vibrations, finite elements method |
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Kudimov N. F., Safronov A. V., Tretiyakova O. N.
Supersonic impinging jet presents practical interest for land development of rocket launch gasdynamic. The multiple supersonic turbulent jets of rocket engines are extremely important for land development, especially because of the fact that there are no experimental data for this kind of flow. The typical cases of interaction between single jets and a barrier are considered in works [1-3], but tasks on interaction between multiple jets and barriers are still under-investigated whereas they are essential during the technical issues solution. Some of these tasks are considered in [4,5]. With respect to distance between nozzles and barrier there are complex three dimensional turbulent flows with subsonic and supersonic flows areas, rarefaction waves, shock and viscous-inviscid interaction in turbulent mixing layer.
This paper presents wall surface pressure distribution at various distances from nozzles to the barrier.
Analysis findings of experimental data can be applied during the development of rockets with multiple configuration nozzles. The obtained data can be used for the verification of calculation programs for determination of multiple jets gas-dynamic impact on various configurations.
Keywords: experimental study, multiple jets, instability of flow |
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Kotel'nikov V. A., Kotelnikov M. V.
Plane electrode can be considered as an element of the surface of a satellite moving in the ionospheric plasma. It can be in front of the satellite, in which case the velocity vector is perpendicular to the plasma flux incident onto the surface thereof. If the plane electrode is disposed on the side surface of the satellite, the velocity vector of the plasma flow is parallel to its surface.
A mathematical model of the problem in both cases involves the kinetic Vlasov equations for ion and electron distribution functions and the Poisson equation for the self-consistent electric field. Maxwell distribution with appropriate values of directed velocities is used as the initial and boundary conditions for the distribution functions. The electrode surface potential is considered as given, while at the outer boundary of the computational domain the potential is assumed to be zero.
If the electrode is represented as an elongated rectangle, the problem is formulated in a four-dimensional phase space. Thus, the problem is time-dependent, multi-dimensional and multi-parameter. A numerical method of successive iterations in time is used to solve the problem. Kinetic equations are solved by the method of characteristics or the Davydov method of large particles, and the Poisson equation is solved by spectral methods. The computational algorithm is optimized and adapted for the computer of Pentium type with medium processing power.
Distribution functions for ions (IDF) and electrons (EDF) for two mentioned cases were obtained as a result of numerical modeling. The self-consistent electric field isolines were obtained also. With the known IDF and EDF, their moments were calculated. The presented velocity profiles of charged particles allow qualitative assessment for the end and edge effects that influence the distributions of ion and electron current densities over the plate in a complicated and non-linear way.
Keywords: parietal plasma, flat electrode, distribution function, satellite, a fully ionized plasma, Poisson equation, Vlasov equation |
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Blinkov Y. A., Ivanov S. V., Mogilevich L. I.
The coupled hydroelasticity problem formulation: the dynamic equations for the both geometrically and physically nonlinear elastic shell, the equations of dynamics of the viscous incompressible liquid being inside a cylindrical shell, and its boundary conditions has been considered. The equation for non-linear deformation waves in shell has been derived by the use of methods of solution for the mentioned hydroelasticity problem. The used asymptotic transition to the classical equation of hydrodynamic lubrication theory becomes possible when the radius of the shell midsurface is significantly smaller than the deformation wave length. The obtained equation has been solved as the generalized and modified Korteweg-de Vries equation including the term corresponding to the liquid impact inside the shell. In the absence of the liquid the equation has a known exact solution which can be considered as an initial condition for the numerical solution of the new equation.
The numerical solution of the Cauchy problem for the new equation considering the effect of the liquid media to the shell dynamics is shown. The formulation of the difference scheme is based on the construction of the predetermined system of differential equations derived from the integral approximation of conservation laws and the integral relations connecting the unknown functions and their derivatives. As a result, the difference scheme is defined as the condition for the compatibility of the system and automatically secures the fulfillment of the integral conservation laws in the domains composed form the basic finite volumes.
The presence of liquid inside the shell results a substantial change of longitudinal deformation waves propagation. If there is no liquid in the shell, a solitary wave (soliton) moves retaining its original shape and velocity. The presence of the liquid in the shell with the Poisson ratio less than one-half results the exponential increase of the wave amplitude under and to the absence of wave oscillations at the forefront due to the energy dissipation. In the absence of energy dissipation the oscillations would occur at the leading edge of the wave. Thus, it can be stated that the liquid contributes to a constant extra “feeding” energy (the original source of excitation), providing for the amplitude growth.
Consequently, the use of these models allows one a widening of experimental data analysis possibilities for various principally non-linear systems: fuel supply, cooling, blood and lymph stream pulsating waves etc.
Keywords: cylindrical shell, non-linear waves, hydroelasticity, viscous incompressible liquid, soliton |
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Development and modeling algorithm to compute the ephemeris prediction, which accounting the Earth rotation parameters in the problem of coordinate-time supporting for navigation satellites.
In order to improve the accuracy of navigation tasks was developed algorithm with the Earth rotation parameters, which are in the differential equations of the orbital motion of the satellite and the matrix of transition from terrestrial to celestial coordinate system and vice versa.
Theoretical modeling of the vibrational-rotational motion of the deformable Earth, appropriate observations and measurements are carried out by using the approximate methods of nonlinear mechanics, combining with numerical experiment. Oscillating process is described by model of the Earth’s pole, which is based on the considering gravitational-tidal torques from the Sun and the Moon. In implementing the transition from terrestrial to celestial coordinate system has been used numerical methods of the celestial mechanics for the calculation precession and nutation parameters, which are recommended by the International Astronomical Union (IAU).
Modeling the orbital motion of the navigation satellites was simulated on the basis of the constructed algorithm in inside revolution time interval within the models of Earth’s rotation parameters, which are adequate observations and measurements IERS and accepted theory of nutation IAU. The results of modeling is shown that the mathematical models used EOP (Earth's poles oscillating process and irregular rotation of the Earth) and the developed algorithms with their directly accounting on the basis of IERS, to extend the time interval and increase the prediction accuracy of the satellite ephemeris.
The developed algorithm for computing the prediction ephemeris within the Earth rotation parameters can be applied to solve the problems of coordinate-time supporting for navigation satellite and other tasks that associated with the movement of the satellites in medium and geostationary orbits. The implementation of the transition from terrestrial to celestial coordinate system with the forecasting ability not only solves the problems, which are associated with the orbital motion of the satellite, but also series of important geophysical, geodetic, astronomical and other tasks.
Keywords: earth’s pole, universal time, preccesion, nutation, navigation satellite, celestial coordinate system, terrestrial coordinate system |
Aviation technologies |
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Zherebin A. M., Toporov B. P., Gorlov V. M.
The paper focuses on pre-design of Complex Aviation Systems (CAS) as the initial stage in the process of creation (modernization, modification) of aircraft with different missions. This is the stage whenfunctional-and-technicalidea (requirements and possibility of creation)and concept of the CAS within the country's aviation areshaped and proved. This is also whenthe rational main performance and parametersas well as the type of the created CASaredetermined.Pre-design stage defines themodes of CAS rational operationand ways of itsinteraction with other systems and complexes, which are involved in the process of CAS creation and operation duringmission fulfillment.
The topic of the paper are the main methodological approaches and methods of solving the key pre-design problems: the problem of CAS synthesis (CAS fleet structure), which consists in determining the rational values of main CASperformanceand parameters (i.e. the performance and parameters that have the greatest influence on CAS mission effectiveness and cost)according to the adopted objective function; and the fleet-type problem, which consists indetermination of qualitative and quantitative composition of the CAS fleet structure under the requirement that this fleet should be able to successfully carry out the whole set of the missions allocated for aviation with the considered purpose.
The paper seeks to improve theeffectiveness and justifiability of the decisions madeduring pre-design via the use of scientifically proven methodology ofthe solution of main design problems.
The paper proposes to simultaneously solvethe problem of rational CAS fleet structure optimization in terms of quantity and type nomenclature together with the problem of optimization of the main performance andparameters of each type ofCASwithin this fleet as a two-level iterative optimization procedure. The first level of this procedure provides fora consecutive solution of two optimization problems: the problem of CAS synthesis for the given set of missions, which are assigned to the fleet and should be carried out by it; and the fleet-type optimization problem, which determines the fleet structureand the distribution of missions among the different CAS types.
The second level (cycle) of the iteration procedure is determined by the correction of the given multitude of missions according to the optimization results obtained at the first level.
The problem of CAS synthesis that is solved at the first level of the iterative cycle is a classical calculus of variations large-scale problem. A decomposition method is used to reduce the length of the control vector. At that structural CAS decomposition is coupled together with the operational decomposition, which aims at selecting main performance and parameters of the CAS subsystems at the lowest possible levels of the operation hierarchy that are described by simpler operation models.
The created hierarchical system of operation models is used during the process of pre-design for the evaluation of the CAS mission effectiveness. At that the method of reversed invariant standard etalon creation is used forproviding solvability of the problems of selection of optimum ways of the CAS operation, which are especially complex at the upper levels of the operation hierarchy. Thismethod allows making unequivocal reverse transition from the reference (etalon) phase coordinates of the operation process to natural ones.
The work resulted in the development of methodological approaches and methodsfor the solution of problems of synthesis and fleet-type structure optimization of CAS, which are intended for carrying out given missions during a conflict under the conditions of uncertainty. At that the missions themselves and the conditions, under which they must be carried out,can change during the considered planning period of time.
The paper describes the above mentioned methodological approaches and methods for the solution of the problems of CAS synthesis and fleet-type structure optimization. These methods allow substantiating the rational values of the main performance and parameters of advanced types of CAS. This justification essentiallymakes up the initial information, which is necessary tostart the design and development of these CAS. This initial information should be adduced in the request for proposal forCASconcept projects. Besides,thecreated methods allow developingversions of rational CAS fleet structurefor various values of the initial dataduringa short period of time.Such development can be carried out for the cases when the accurate forecast of the initial datafor the planned period of timegives only an interval estimate orisessentially impossible to make. The development of such versions of rational fleetsgives the necessary baseline for advanced planning of the creation and production of CAS. Keywords: external designing, synthesis, shape, type and park of aviation complexes, operation modeling, decomposition |
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Nyi N. H., Kyaw H. -., Markin L. V.
The subject of this research paper is the development of the mathematical methods and software of computer-aided design for aviation technology. We consider the computer-aided design system for connecting the routes between already placed objects, particularly electrical wiring, pneumatic and drainage systems, hydraulic systems; this problem seems to be more difficult that the development of the systems of automated arrangement of airplane’s technical compartment. The dimensions of the routes between already placed objects, the objects dimensions, and the minimal radii of curvatures can be compared and they must be variable; this is the main peculiarity of the considered problem.
The use of the discrete grid-based method based on the receptor geometric model which simulates the basis designs of the routes in layout space for the design algorithm is proposed. Advantages and disadvantages of the use of the receptor geometric models were also described in the presented paper. Thus, the advantage of the proposed method is the possibility of an effective direction search at each step of the route design, and its ability to determine the intersection of the projected route with the pre-composed objects. The drawback of this method is an inability to secure the smoothness of the projected track, and its high requirements to the computational power. However, the computational power of modern computers provides a practical implementation of this method.
The main obtained result consists in the development of the simulation software in C# and testing of routing algorithm between already placed objects. The possibility of the algorithm to find effective obstacle avoidance (as already arranged objects) is shown and more options are available to smooth the path to reach the required minimum radii of curvature. Due to the new data structure of algorithm in improvement for speed compared to traditional routing solution with discrete-tracing algorithm A* (A-star), new algorithm is about 1300 times faster than the classic A* and approximately 15% more effective compared to using the most effective modifications of A* algorithm by Masatomo Kanehara.
The scope of application of the obtained results is the computer-aided design system for aircrafts and other transport systems, i.e. technical objects with a high density layout. However, an additional difficulty of wide practical application of this method is the need to develop a transition module for the conversion of geometric parametric models used by designers and specified in drawings in a geometric model of the receptor (in fact, intra-machine), and need to use back and forth.
As a result of the investigations, the possibility of the use of a method of computer-aided design of the connecting lines of a given size and minimum radii of curvature of the objects is shown; a relatively short computation time is need (few minutes). The essential difference between the existing algorithms and proposed one is the ability to modify the size and length of the tracks directly in computation process. Another features and applications of the algorithm is beyond the scope of this article (e.g. related research - Masatomo Kanehara algorithm - was created to design the route obstacle avoidance robot manipulator).
Keywords: designing, route tracing, receptor geometric modeling, physical trace, canal surface, obstacle avoidance, path smoothing |
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Ignatkin Y. M., Makeev P. V., Shomov A. I.
The paper is focused on the problems of providing flight safety for a single-rotor helicopter at special flight modes. At these modes the tail rotor can be exposed to some conditions, under which its aerodynamic characteristics change drastically. In case of tail rotor thrust decay its effectiveness as a control unit decreases. This can lead to loss of directional trim of the helicopter, its uncontrolled rotation and crash.
The paper aims to carry out the computational study of main and tail rotor interference during vertical descent of the helicopter, including the range of vortex ring states of the main rotor.
The research was carried out by using the specially created software, which is based on the non-linear rotor vortical blade model developed at the “Helicopter Design” Department of MAI.
The research was carried out for a calculation model of main and tail rotor combination of Mi-2 helicopter. The case of horizontal flight with angle of attack of main rotor αн = 0º and flight speed V = 10 mps was modeled during the research.
The descent with the range of speeds Vу = 0…15 mps for angle of attack of main rotor αн =0º was considered. The shape of the free vortical wake of main and tail rotors was built for the mentioned above modes with and without taking into account interference. Diagrams of induced velocities of main rotor vortical wake in the area of tail rotor location were constructed. Reasons of interference effect emergence were analyzed and its influence on tail rotor aerodynamic characteristics was estimated.
As a result of the research it was established that main and tail rotor interference develops to a large degree at vortex ring state mode of the main helicopter rotor. At that the interference is determined by vortex wake structure of the main rotor and its location relative to the tail rotor. In addition the severity of exposure of the tail rotor to main rotor influence depends on the operation mode and rotation direction of the tail rotor. The research results show that the decrease of tail rotor thrust due to interference reaches its maximum of 26 % compared to the trust of the isolated tail rotor at Vy = 6 mps. At that the main rotor works in a mode of intensive vortex ring state and the tail rotor ends up in the core of the main rotor vortex ring and gets exposed to heavy influence of its inductive velocities field.
The research results can be used for estimating and choosing optimal direction of tail rotor rotation and determining directional control margin during design and modernization of helicopters.
Keywords: main rotor, tail rotor, computational methods of rotor's aerodynamics, non-linear vortical model, vertical descent, rotor interference, aerodynamic characteristics |
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Ignatkin Y. M., Makeev P. V., Shomov A. I.
The paper is focused on the problems of providing flight safety for a single-rotor helicopter at special flight modes. At these modes the tail rotor can be exposed to some conditions, under which its aerodynamic characteristics change drastically. Herewith in case of tail rotor thrust decay its effectiveness as a control unit decreases. This can lead to loss of directional trim of the helicopter, its uncontrolled rotation and crash.
The paper aims at carrying out the computational study of main and tail rotor interference during low-speed horizontal flight with sideslip.
The research was carried out by using the specially created software, which is based on the non-linear rotor vortical blade model developed at the “Helicopter Design” Department of MAI.
The research was carried out for a calculation model of a combination of main and tail rotor of Mi-2 helicopter. The case of horizontal flight with angle of attack of main rotor αн = 0º and flight speed V = 10 mps was modeled during the research.
The helicopter sideslip angles within the range of βн = -90…90º with pitch 10º were considered. The shape of the free vortical wake of main and tail rotors was built for the mentioned above modes with and without taking into account interference. Diagrams of induced velocities of the main rotor vortical wake in the area of tail rotor location were constructed. Reasons of interference effect emergence were analyzed and its influence on aerodynamic characteristics of the tail rotor was estimated.
As a result of the research it was established that main and tail rotor interference develops to a large degree at the considered flight modes. At that the interference is determined by the vortex wake structure of the main rotor, which forms two secondary vortex cores at horizontal flight modes, and the location of the mentioned vortex cores relative to the tail rotor. It was shown that the severity of exposure of the tail rotor to main rotor influence depends on the operation mode and rotation direction of the tail rotor. The research results show that the decrease of tail rotor thrust due to interference reaches its maximum of 26 % compared to the thrust of the isolated tail rotor at βн = -50. It was established that the counterclockwise direction of tail rotor rotation (upper blade moves backwards) is optimal in terms of influence of interference on its thrust.
The research results can be used for estimating and choosing the optimal direction of tail rotor rotation and determining directional control and stability margins during design and modernization of helicopters.
Keywords: main rotor, tail rotor, computational methods of rotor's aerodynamics, non-linear vortical model, horizontal flight mode with a sideslip, rotor interference, aerodynamic characteristics |
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Kuporosova E. S., Milehin L. N., Maksimov E. Y.
An oscillate-base shock-absorbing suspension of the payload on the oscillate platform.
Determination of the most optimal construction scheme for shock-absorbing suspensions of the payload on the oscillate platform. The mechanical movement model of the suspensions systems was developed by Lagrangian approach. The frequency-response characteristics of the models were researched by using the transfer functions. The disturbance motion of the shock-absorbing suspensions was simulated with the polyharmonic vibrations of the platform.
The operation quality parameters of the different suspension schemes are detected:
1) value of the amplitude-frequency characteristics;
2) root-mean-square error vertical coordinate for the shock-absorption object.
3) effectiveness factor of the vibration protection equal to ratio low bound of the frequency spacing of vibration to natural frequency of the shock absorption object.
This paper describes the different schemes developing of shock-absorbing suspensions of the payload with the oscillate platform. The best model parameters were reached for the three-stage scheme. This scheme has a following structure: shock-absorption object– intermediate frame (rubber cords), intermediate frame – support (rubber cords), support - platform (shock absorbers).
Keywords: polygarmonic, shockproof suspension, payload |
Space technologies |
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Modeling the fundamental components of the Earth’s rotation parameters for solving navigation problems.
Develop a few-parameters model for forecasting the movement trajectory of Earth's pole within short time intervals for some navigation problems.
Theoretical modeling of the vibrational-rotational motion of the deformable Earth, appropriate observations and measurements are carried out by using the approximate methods of nonlinear mechanics, combining with numerical experiment. Oscillating process described by model of the Earth's pole is based on the considering gravitational-tidal torques from the Sun and the Moon.
The numerical simulation for the model is made, providing a set of basic functions and the estimation of the unknown coefficients. The calculations were carried out by setting up the filtering algorithm of the International Earth Rotation and Reference Systems Service's (IERS) data observations with the least squares method. The length of interpolation's interval, or in the other words the number of the measurements processed, depends on the total estimation’s error for the given set of based functions in attempt to minimize the error.
Using the mathematical model of the Earth's polar motion, which is constructed by applying celestial mechanics’ methods, an interpolation and forecast of the trajectory of the Earth’s pole are obtained. Intervals of interpolation vary between 30 and 60 days and forecast based on such interpolations is made for short time intervals, from 15 to 40 days. The comparison between the constructed model for different time intervals and the IERS-provided observations is made. The value of the standard deviation of the theoretical curve from the experimental one, obtained by using IERS data observations during the respective time intervals of the filtering algorithm, the interval settings, proves the sufficient accuracy of the constructed model. When being placed into the real environment with the up-to-date IERS observations’ data the higher accuracy for the short-term forecast is achieved by taking into an account structural properties of the few-parameters model. One of the main perspective applications of the mathematical models of the Earth’s motion is to improve the orbital-rotating parameters of a flyby because for the modern the space technology and telecommunication systems the accuracy of the coordinate-time support is of a great importance.
The forecast of the fundamental components of Earth’s rotation parameters at a short time interval (up to 40 days) allows much more accurate estimation of the parameters of the satellite's orbit, which in turn provides a significant increase of the accuracy of the forecast of satellites’ ephemeris calculated for the following days.
Keywords: fluctuation, earth’s pole, alteration of latitude, prediction, gravitation tide |
Aerospace propulsion engineering |
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Rebrov S. G., Golikov A. N., Golubev V. A., Molchanov A. M., Yakhina G. R.
The object of the article is a research of the mixing process in the simulated combustion chamber with laser ignition for hydrogen-oxygen and methane-oxygen propellants.
The goal of this work was to confirm location of the initiation ignition zones and work conditions of the laser in experimental researches of the laser ignition system with hydrogen-oxygen and methane-oxygen propellants in the combustion chamber by the use of numerical simulation.
For validation of the choice of ignition zones, which were used in the experiments, the numerical simulation of the mixing process in the combustion chamber and analyses of mixture ratio before the laser cut in were conducted. ANSYS ICEM CFD was used for creating mesh model and ANSYS CFX was used for the fluid dynamic simulation. The cyclic sector of sixty degrees with symmetry condition was created. This decrease calculation time and computational capability of simulation process. The grid model consists of 547618 elements and 579059 nodes. The steady-state and transient problems were simulated. The solution of the steady-state problem shows the mixture parameters in stabilized conditions. The transient problem is useful for more detailed study of mixing process, when the components start to flow in the combustion chamber.
The results of the experimental researches are data on mixture ratio in focusing points of laser beam for hydrogen-oxygen and methane-oxygen propellants. According to the results a reliable ignition was achieved by initiating spark optical breakdown in the areas with excess oxidant ratio α = 0,4..0,5 and α = 0,75 for hydrogen-oxygen mixture and α = 0,3 and α = 0,6 for methane-oxygen mixture.
The results of the transient problem confirm the conclusion of experimental researches that the simultaneous fuel-feed and laser cut-in (regime 20Hz) provide “smooth” ignition without overpressure in the combustion chamber.
The researches confirm reliability of the laser ignition. It may be used in a full-scale rocket engine and in a gasifier of different purpose.
Thus, this work demonstrate that the results of numerical simulation of the propellant mixing process can be used for prediction of optimized focusing zones in a liquid rocket engine, which allows to ignite the propellant mixture with a minimum pulse energy.
Keywords: numerical simulation, laser ignition, combustion chamber, rocket engine, optical breakdown |
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Vazhenin N. A.
According to recent studies of the thin time structure of stationary plasma thruster (SPT) radiation, in addition to a purely thermal component this stochastic process contains a non-thermal one representing stochastic sequence of radio pulses with complicated internal structure. This radiation represents interference for the space communication systems.
The purpose of this paper is to discuss development and investigation of simulation models of the SPT non-thermal interference electromagnetic radiation.
In view of considerable mathematical complexities related to the adequate description of pulse interference and to the application of analytical methods of interference immunity investigation for various algorithms of reception, the development of simulation computer models for SPT radiation is of great practical and theoretical interest.
The specialized program complex has been developed for simulation modeling of SPT impulse electromagnetic radiation, allowing generating a random sequence of complex pulse signals with the given statistical characteristics.
The program complex developed on the basis of a complex envelope method allows generation of random sequence of radio pulses having the given distribution laws of amplitude characteristics, repetition intervals, duration, the given form of an envelope, duration and carrier frequency for each pulse.
The developed model of SPT radiation showed good agreement with test measurements of SPT radiation, and can be used for modeling and prototyping algorithms of signal procession in space communication systems.
This study provides a starting-point for further forming simulation models of stationary plasma thruster radiation.
The results obtained can be used to analyze the effects of stationary plasma thruster radiation on the operation of space radio communication systems.
Keywords: space communication, pulse noise, stationary plasma thrusters, mathematical model |
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Davydov A. V., Degtiarev S. A., Ivanov A. V., Leontiev M. K.
Annular seals in turbopumps influence their rotor dynamics significantly. They cause rotor autorotation and may result in the stability loss. The results of modeling for the rotor with hydrodynamic seal in the Dynamics R4 program system environment and their analysis are presented in this paper.
Rotor of the hydrogen turbopump on two supports was the subject of our study. Double deep-annular bearings were used in the supports. Circular vane-type dry-friction damper supports were placed between the case and the bearing outer rings. Tightness of the air-gas turbine and impellers may be provided by annular seals of different types including those with floating rings. Finite elements being the parts of the program library, such as the rod beam elements, inertia elements, elastic and rigid links, etc., were used for the rotor modeling. Every rotor component was simulated separately and was included into the complete rotor model as a separate subsystem. Links simulating junctions and fits in the rotor and its supporting units were specified between the subsystems. The bearings were loaded by axial forces.
The analysis was carried out in linearized and nonlinear statement. Linearized statement may be used only for typical annular seals or if friction forces stop a seal ring. Stiffness coefficients Kxx, K xy and damping ones C xx, C xy were calculated using the procedure developed by Childs for an annular seal. Such coefficients are the functions of seal geometry, rotor speed, liquid properties, and differential pressure. They are defined for the central shaft position in clearance and are used for the analysis in the linearized statement. In nonlinear analysis it is supposed that the ring has inertia, and it is affected by hydrodynamic and friction forces. With such statement, solution is found by direct integration of the rotor system motion equation with the determination of a seal reaction on the rotor and the ring at every integration step. To define the seal reaction, the algorithm, that allows determination of the annular seal hydrodynamic force with consideration of the rotor motion and tracing such force influence on the rotor and ring dynamics, was developed. It is shown that sometimes hydrodynamic force appearing in seals may exceed the rings friction, and they start moving, changing the rotor dynamic characteristics.
Keywords: rotor dynamics, nonlinear models, floating rings, Dynamics R4 |
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Volkov A. A., Mishchenko V. Y.
The paper adduces a method of determination of individual components of power losses in power supply units of hydraulic systems.
Determination of individual components of volumetric and mechanical losses in hydraulic pumps of power supply units allows to define the following: the temperature conditions of the hydraulic machine; loads acting on the structural elements, many of which (piston bearings, a flat fixed valve, a face seal) are essentially hydrostatic bearings. Besides such determination allows to select the right structure of the pressure and consumption unloading system, which leads to reduction of some individual components of the losses.
The paper presents a mathematical model of the hydraulic machine efficiency depending on dimensionless groups, which describe its mode of operation as well as structural and technological quality of its implementation. These groups include coefficients of working fluid leakages, dry and fluid friction coefficients. Coefficients of similarity of operation modes of the hydraulic machine depend on the statistical coefficients of individual types of losses, which can be defined on the basis of experimental research of various types of pumps.
The defined above dimensionless groups and their connection to the quality parameters (leakage and friction coefficients) indicate the areas of optimum operation of power supply units and hydraulic machines.
Experimental research, which is connected to volumetric losses via the pump control mechanism, was conducted. Pressure fluctuations in the pressure pump line, overpressure upon activation of hydraulic power consumers and service life of the pump depend on the performance capability of this pump control mechanism.
The operation of the pressure and consumption unloading system leads to the change of the control system configuration. A transition from the differential throttle control system to the direct acting regulator and vice versa takes place. This transition is accompanied by the change of loadings on the feeder control unit and change of the components of the volumetric losses, the value of which should be determined for the specified operation modes.
The results of the research can be used for the design of power supply units with pressure and consumption unloading. The application of the proposed method results in significant reduction of heat emission both in power supply unit and in the whole system. This in turn reduces the weight of the heat-exchanger devices respectively.
Keywords: the hydraulic machine, the axial-piston pump, operation mode coefficients, volumetric and mechanical losses, performance efficiency, pressure and consumption unloading, friction coefficient, volumetric losses coefficient, parameters of hydraulic machine control |
Control and navigation systems |
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Savchenko D. I.
The increasing of the efficiency of situation coverage in the information and control systems of various carriers is achieved by solving the task of association target data fed by all information sources. But for all that two results of this method sequential applications could be different, e.g. in consequences of mistaken decisions about associations. In condition of associated targets data being changed appears a need in maintenance of targets data identifiers (numbers), trying to keep them stable with the time.
The purpose of the work is to specify and analyze the requirements of the problem of the associated targets numbering in the information and control systems of various carriers, and create the algorithms that would solve the assigned task.
The method of system analysis and the method of formalization with set theory applied were used as the main instruments in the performed work.
The main results of the work are:
a) a specification of the requirements for getting a stable associated targets numbering system, for the easing of the situation estimation by an operator and ensuring tasks solution regularity in the information and control systems;
b) a combination of algorithms of the numbering task solution has been proposed, that satisfies original requirements.
The main algorithm to solve a problem of associated targets numbering has a linear complexity relative to amount of targets. Other algorithms have a linear complexity relative to amount of the sources or constant complexity.
The offered algorithms could be used in the information and control systems that need to process and associate the targets data, fed by the several sources, including the control systems of surface ships and vessels.
Offered requirements and algorithms are generic and could be used in many different information and control systems. For a given control system some requirements could be precised or reduced with an opportunity to simplify applied algorithm.
Keywords: information and control systems, association, information sources, target situation, tertiary processing, target numbering |
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Savchenko D. I.
The association of targets data fed by few information sources is an effective way to increase comprehensiveness and reliability of the covering situation in the information and control systems of various carriers.
In the real systems the association task is being solved regularly, what gives an opportunity to increase the probability of making correct decisions using accumulation and taking into account previous association results.
The purpose of the research is to develop a decision rule and an algorithm meant to increase probabilistic characteristics of target data association from two information sources with the help of accumulation and taking into account the decisions made in previous invocations of the task.
A graph theory and combinatorial optimization were used in the work. The decision rule is made by the generalization of the majoritarian decision rule, and the algorithm is made by the reduction to the Assignment problem. Mathematical modeling and simulation were used to check correctness of the proposed approach.
The main results of the work are the decision rule and the algorithm meant to increase the probabilistic characteristics of the target information association. The complexity of the algorithm is polynomial and it is the most efficient algorithm compared to other known analogues.
Modeling and simulations with experimental data have proved the increasing of the probabilistic characteristics. Particularly the usage of the proposed algorithm for conditions described in the paper resulted in the same probabilities of correct decisions in situations where the distances between targets have been reduced in 1.2 times.
In the great number of being upgraded and developed information and control systems of various carriers the association of targets data fed by several sources task is solved by reduction for the number of solving the task association of data fed by two sources. In this way proposed algorithms could be used in the real information and control systems, where the processing and association of the targets data fed by the several sources tasks are being solved, including the systems of surface ships and vessels.
The proposed approach allows increasing the probabilistic characteristics of target information association without increasing complexity of the association algorithm, which consequence in the increase of the efficiency of the situation coverage and solving of the typical tasks for given information and control systems. It means that described approach could be useful in practice.
Keywords: association, information sources, target situation, tertiary processing, information and control systems |
Electrotechnology. Electromechanics |
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Zhuk A. Z., Ilyukhina A. V., Pushkin K. V., Sevruk S. D., Farmakovskaya A. A.
The specific energy characteristics of air-aluminium (AA) electrochemical generator (ECG) with alkali electrolyte are higer than for nickel-cadmium and nickel-hydride batteries, which are traditionally used in aerospace techniques.
To provide the high efficiency index of aluminium as anode material in ECG it is necessary to decrease its corrosion rate in alkali electrolyte to the utmost without degradation or with certain increase of its activity in current-producing process.
On the basis of the research performed earlier it was discovered that the composition of anode (aluminium-indium alloy А995 + 0,6 масс.% In) and electrolyte (4М NaOH + 0,06M Na2SnO3⋅3H2O) have meet all the requirements. Indium in the anode alloy fulfils a function of depassivating agent and ion stannates in alkali electrolyte inhibit its corrosion.
However in the ECG working process the tin from electrolyte deposits in the metal form on aluminium surface. In the anode corrosion process it precipitates onto the interelectrode gap in the form of a sludge that can result in interelectrode short circuit. Therefore, the critical task is to search the alkali corrosion inhibitors for aluminium anodes alternative to stannates and to examine their influence on the electric, energy and operational characteristics of AA ECG.
The paper contains the results of the experimental research of the influence of the admixtures of a number of organic aluminium corrosion inhibitors to AA ECG alkali electrolyte on these characteristics. The research was performed at the temperature of 333К. It were obtained polarization and corrosion characteristics for the following combination: A995 aluminium and Al-In anode alloy in 4M clear solution of NaOH with the addition of 0,052М potassium citrate; for the same alloy and for АП4Н protect alloy in 8M clear solution of NaOH; in the same solution with the admixtures of 0,06M Na stannate (for reference), 0,01M citrate and 0.01M sodium benzoate.
The research has shown that above mentioned admixtures decrease polarization characteristics of aluminium indium anodes reducing their corrosion rate. Besides, their usage leads to the negative difference effect as opposed to alkali stannate electrolytes that demonstrate the positive difference effect. Therefore, the organic inhibitors that have been examined could find limited application in AA ECG.
Keywords: aluminium, anode, air, corrosion, organic inhibitor, polarization, characteristic, electrochemical cell, alkali, electrolyte, electric power plant |
Radio engineering. Electronics. Telecommunication systems |
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Vovasov V. E.
Theobjectiveofthisworkisthecorrectionof radial velocityofhighly dynamic objects applying the signals of GLONASS and GPS navigation satellites, taking into account both thesatellite signal lags, andetherodynamics phenomena.
Allthemostessentialphenomena of relativitytheory onthereceivingofnavigationsignalssuchasthe gravitationalred shift, the rotation rate of GLONASS satellitesand planetsperihelion, the light deflection in the gravitational field have been considered.It has been also testified that all the corrections related to the effects of the special relativity theory should be substituted with the corrections of the theory of signallag and the corrections related to the effects of general relativity theory should be completed with the corrections of etherodynamics. The corrections to the Doppler frequency formulation related to the radial acceleration of navigation receiver and relative shift of signal frequency per distance unit occasioned by the viscosity of the ether have been obtained. Suchcorrections let explain the “red” shift of star and galaxyspectra without universe extension hypothesis and the implementation of these corrections requires the experimental verification by means the algorithms proposed in this work.
Comparative study of difference between the gravitational force acting on a body at rest and the Newtonian force has been carried out as in the frame of general relativity theory so in the theory of signal lag. It’s shown that the gravitational force formulation obtained on the basis of the theory of signal lag without introducing the concept of the “Dark matter”allows one to explain the existence of the radial marginal stars of galaxyacceleration greater than the acceleration evaluated by the gravitational attraction of the galactic center, calculated according to the formula of Newton.
Keywords: theory of delay of the signals, special and general relativity theory, GLONASS and GPS |
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Vazhenin N. A.
As investigations have shown, the electromagnetic radiation of stationary plasma thrusters (SPT) represents a broadband random process, the spectral power density of which is from some tens of Hz to some tens of GHz. This radiation represents interference for space communication system channels. The purpose of this paper is to assess influence of the SPT electromagnetic radiation on noise characteristics of space communication systems.
Space communication systems are relatively narrow-band ones in many cases. But according to the results of experimental studies, the SPT radiation is a broad-band process at the same time. For the preliminary analysis of interference immunity of such communication systems under the SPT radiation influence the model in a form of the additive white Gaussian noise in the receiver band can be used. As a first approximation, such approach allows rather simple quantitative assessment for the influence of SPT radiation on quality characteristics (reliability, operational range, data transmission rate, etc.) of communication systems.
Calculations show that under such assumptions for the operating SPT the signal-to-noise ratio may become worse by 2-8 dB at the initial noise temperature of the system from 100К to 10К. In this case, the maximum range of communication system Earth-SC can decrease by 1-4 dB that is potentially more than 2 times.
Thus, under certain conditions the SPT self electromagnetic radiation can interfere substantially the noise characteristics of space radio communication systems.
In this connection for minimizing the influence of SPT radiation on space communication systems it is necessary to undertake special measures.
Results obtained may be used to analyze the SPT radiation influence on the operation of space communication systems.
Keywords: space communication, stationary plasma thrusters, product resistance |
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Grubrin I. V., Ligina I. U.
In this paper, we propose the direct inversion of matrix interference algorithm with respect for the criteria of maximum signal-to-noise ratio as the solution of the adaptive interference filtering problem in the multi-channel on-board systems. The use of the proposed adaptive structure allows one to take into account the properties of the timing filter, unlike the known structures with gradient adaptive processing algorithms, which have a low rate of convergence as one of their disadvantages. The structure of adaptive processing is implemented on the basis of multiply-delay line weights in the channels of each tap, which are building not only matched filter, but also take into account the different properties of temporal frequency filter.
As the result of mathematical transformations, it can be shown that the proposed algorithm takes into account the frequency response of the temporal filter. When one changes the characteristics of the spatial filter it leads to the increasing of the signal-to-noise ratio in comparison with the known structures of adaptive signal processing.
The proposed algorithm can build the correlation matrix of the noise for a quick release to the extreme interval, and then it relies on the well-known gradient algorithm at regions of extremes. As a result, it will significantly reduce the computational error and increase the speed of convergence. Keywords: criteria of maximum signal-to-ratio, adaptation, algorithm, filtering, temporary filter |
Economics and management |
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Borisov Y. A.
The purpose of this work is to develop a price setting procedure based on conditions of total profit maximization.
Monitoring certain market characteristics viewed as a relationship of product demand to its price is taken as a basis of this study. The price setting procedure has been considered in a situation when a company cuts down its product costs as a result of improving its production process. A notion of profitability parameter depending on the profit rate is introduced as well as an equation of relative profit change depending on this parameter and relative changes in prices and product sales is derived. This equation defines how minimum gain in sales depends on a price cut provided that the company’s profit remains the same.
A market behavior characteristic in the form of at least two points in the coordinate plane is used to find a relative parameter of price reduction corresponding to maximum profit: relative price variance — relative change in sales. The data result from the analysis of answers given by a group of market experts or directly by the potential buyers of products. With two available reference points a second-degree polynomial is chosen as a market characteristic: an optimal price variance is found using standard methods for finding the maximum of a function.
Methods of analytical determination of an optimal product price if a real market characteristic is available.
The company management marketing policy in conditions of product cost reduction.
Keywords: increase in profits, product profitability, price forecasting, market analysis |
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Mikhailova E. A., Remizova N. A.
It is now one of the most progressive ways to improve cost management is the process of budgeting. Budgeting as the tool of financial planning is an effective way to improve the quality of cash flow management and activities of the enterprise as a whole.
The study of the problem formulation and implementation of the budgeting system was carried out at enterprises engaged in the development of radio electronic equipment, airborne and ground-based measuring complexes in the context of research and development. This sector was chosen because at the moment is one of the most promising and developing directions in the innovative sector of the economy.
The problem of budgeting system for the design organizations is very urgent, since the construction of the system must take into account the specifics of the sufficient conducting research and development at all stages of the life cycle by means of optimization of the management system.
The purpose of research is the study and development of the system of budgeting, as the directions of improvement of management of the project organization, and practically the methodology and its implementation.
Budgeting innovative projects of the enterprise will allow increasing the accuracy of planning of innovation expenses. As separately the control system of expenses for research and development is not allocated hence cost planning is static. Therefore, the study developed a mechanism to control costs. The main purpose of this mechanism is effective communication between the basic elements of management and information flows necessary for management by expenses at a stage of research and development.
For budgeting system design organizations was developed an algorithm for the formation of the process of budgeting and budget model with the release of project budgets and block budgets concerning budgeting of investment and innovation activity.
To ensure the above mentioned model of budgeting is necessary to change the organizational structure of management. For design organizations are invited to use the matrix structure in conjunction with venture capital management system of innovation. The matrix organization is a project management system, which avoids the disadvantages by providing a clear separation of management and professional liability insurance for the project. The main purpose of the venture management is to ensure the maximum responsibility of the progress of innovation by «the head of venture capital». Venture management together with a matrix management allows for the implementation of projects not only in contracts financed by external organizations, but also after the researches and development which are carried out from own means.
Initially budget model is built from the budget of the project, which allows for an assessment of the cost of the project and cost management throughout the entire life cycle of innovation. Data for individual projects are consolidated and aggregated at the level of groups of projects, directions of activity and the organization as a whole. On the basis of these data is held financial planning, planning of the balance sheet, the planning calculation result, the planning of cash flows for the organization as a whole.
On the basis of the organization’s strategy and the approved indicators of the planned investment budgets, with the subsequent formation of the budget for development. Development budgets are essentially of a portfolio of projects accepted for implementation and planning. On the basis of development projects is formed consolidated budget innovative enterprises. Taking into account the peculiarities of the stages of realization of the innovative project was developed scheme of sequence of the formation of the budget of development.
In the framework of implementation on the use of the system of budgeting and cost management mechanism is currently being developed model of evaluation and planning costs on themes and stages of research and development which would allow the management of deviations from the planned indices on stages to themes of research and development as a whole.
The pre-contractual stage to perform the work planning of volumes of expenses on budget periods is carried out on the basis of empirical data on the analog works or generalized method of cost allocation in accordance with the planned dates of execution of research and development.
Based on the planned structure of the price proposed to control costs by using an optimization model of cost management. The essence of the model is the application of the coefficients of similarity and prices, reflecting the changes of the corresponding indicator on the structural elements rates. Multivariate calculation at different levels of cost indicators is to allow the model impact on change in profit work, and, therefore, allows for analysis of the overall financial situation of the enterprise.
The direct control of expenses over performance of works on a theme is requested to using earned value cost index, which allows visualizing the cost savings and the backlog of work plan, as well as on the basis of the dynamics of these indicators to predict the actual performance of work and costs.
The developed method of budgeting and model evaluation and planning costs can first get an overview of the development of innovative business strategies, and then thoroughly investigate all significant deviations from targets in the context of each element of the cost structure.
Approbation of the developed tools of system of budgeting is carried out on OAO "KB"Lutch". Results of use of system show a significant increase in the reliability of estimates of planned costs and high reliability of their temporal distribution. This approach fully meets the requirements of the market, since its implementation costs for the project are managed in the early stages. The study shows that the use of budgeting increases the efficiency of management decisions by more than 50%.
Application of developed system allows is system to operate a concrete direction of research and development due to detailed forecasting both duly updating затратной and a profitable part of the budget, and also to lower financial risk.
Keywords: mechanism of budgeting, innovation project, management cost |
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Yampol'skii S. M., Golovin V. Y.
The research is to provide the delivery of supplies for aircraft after-sales service.
Subject matter of work are pressing questions of automation of delivery of supplies for aircraft after-sales service.
The analysis of existing Russian and foreign systems of information support of processes of operation of aviation technics has shown, that these systems have the limited application for planning of delivery of supplies for military aviation technics as do not consider accidental character of the training and combat tasks solved by the maintaining organizations.
Objective of work is to improve the delivery of supplies management on the basis of the automated planning. Thus it is offered to use the logistical approach to formation of the management strategy, consisting in integration of management functions into the uniform complex providing the maximal prize at the minimal losses.
The logistical approach in planning of delivery of supplies assumes reception of the actual information about required quantity of supplies for performance of training and combat tasks at any time as required. For realization of such approach automation of processes of daily activity of engineering-aviation service is required.
In work the automated planning engineering-aviation maintenance of an aviation unit with use of a software "Forecast" is spent. In a basis of this software used the likelihood analytical model of the engineering-aviation maintenance processes created on the base of markovsky discrete processes with continuous time.
For performance of objectives of work the functional model of process of planning supplies developed and presented, as well as the numerical example of the automated development of a plan of engineering-aviation maintenance of training and combat tasks of aviation unit is considered.
As a result of automated planning the strategy of delivery of supplies is defined on a considered temporary interval.
Such task can be solved by officials of engineering-aviation service, as at a stage of preliminary planning of engineering-aviation maintenance, and during training and combat tasks.
Keywords: delivery of supplies, material support, automated planning, model of the functioning, engineering-aviation maintenance, after-sales service |
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Opryshko N. V., Opryshko Y. V., Ruban N. V.
One of the main indicators of competitiveness of an air carrier is the low cost of airline tickets subject to compliance with safety and comfort standards. An aircraft corporation, which is be able to offer the cheapest aircraft to operate, can force the competitors out of the market and strengthen its position in the global market of civil aircraft.
The cost per flight-hour is the criterion that takes basic operating costs of the using a passenger aircraft (airport charges, ownership, fuel per flight-hour, flight crew and cabin crew, aircraft maintenance) into account. This criterion does not consider the time factor, and this can lead to unacceptable errors in the comparison of aircrafts with different flight technical and economic characteristics.
Research objective is creating a dynamic model to calculate the cost per flight-hour passenger aircraft, taking a time factor and variability of environment into account.
We use methods of forecasting and time discount.
To calculate the hourly cost of aircraft ownership, we have to divide the amount of discounted lease payments of wet leasing into aircraft cumulative life; the received sum will reflect the hourly cost of aircraft carrier ownership.
If the lease agreement provides that the lessee bears the operating costs, it is necessary to divide labor-intensive characteristic of regular service with the annual indexation and target price of materials for repair, given the current moment of discounting cash flow, into the frequency of the work performance.
The cost of the flight crew including stewards is offered for calculation as a sum of wages and insurance contributions, indexed with allowances made for inflation and modified to current point in time, divided by the cumulative life of aircraft in hours.
To calculate cost of aviation fuel per flight-hour we have to determine the average cost of 1 ton of fuel for the entire statutory service life of the aircraft and bring it to the current point in time. The calculated expected average cost of fuel inclusive of the dynamics of change in the price will reflect the actual cost of fuel over the operating life of the aircraft.
For the distribution of airport charges per flight-hour, we propose to multiply the amount of expenses tо ensure takeoff and landing by the statistical or normative number of takeoffs and landings and divide into the cumulative life of aircraft in hours.
The suggested model is focused primarily on airline executives to support decision making in choosing the aircraft. However, the use of this model will allow managers of Aircraft Corporation to assess the real competitiveness of aircraft manufactured by the corporation and looking for methods and ways to improve it.
Resulting from the use of this model of the flight-hour cost is probabilistic in nature and has a certain level of uncertainty associated with projected value of indicators which are used in the model. However the accuracy of cost accounting in this case would be much higher than using a fixed value of cost of flight-hour. Keywords: civil aircraft, competitiveness, operating cost, cost of flight-hour, lease payments |
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Кalugina G. A.
Aircraft production industry is a very knowledge-intensive sector. Its effective operation is very essential for provision of government social-economical development.
In the conditions of competitive market, such as Russian and world market of civil aircraft, the necessary condition for obtaining commercial success is an increasing of competitiveness of civil aerotechnics, that depends on variety of parameters: aircraft performance and operation characteristics, reliability, safety, economical characteristics, comfort and ease of maintenance, standardization and certification, additional services and guaranties.
Along with above mention there is a factor “aircraft family” that has influence on appeal of product proposal of aircraft production companies.
Marketing research plays an important role while definition of directions of aircraft family development. It is reasonable to you strategic analysis instruments for generalization of results of market and production resources analisys.
Therefore the subject of the article is definition of a role and possibilities of marketing research and marketing analysis in elaboration of strategic alternatives of product offering development of aircraft-production enterprise.
In consideration of the premises the theme of the article – marketing research of aircraft production enterprises aircraft family elaboration.
The objective of the work is to determine the civil passenger aircraft competitiveness increasing directions on internal and on the world market.
The method of the work is system analysis of internal and external environment while strategic decision making and complex estimation of market potential of variants, competitive environment perspectives changes, construction technological and operation characteristics of the current variants. This provides to select the most efficient aircraft family development variant taking into account a degree of creation possibility and influence intensity of above mentioned factors.
The results of the work are showed by the example of feasibility evaluation of SukhoiSuperjet 100 aircraft family development variant by Sukhoi Civil Aircraft Company.
The example characterize a result aria use, that could be determined as plans feasibility increasing of aircraft production company.
On the basis above mentioned it is possible to make a conclusion that company internal and external environment marketing research plays a key role as well as a proper interpretation of research results made with strategic analysis methods, during definition of aircraft production company output program. Keywords: aerospace industrial equipment, product offering, market research, strategic analysis, family of flyers |
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Ageyeva N. G.
Changes in organization and management of aviation systems design are connected with the need of transition of the design organizations to a new stage of development. At the entry into the world market it is desired not only to update and modernize the administrative system but also to change the process of life cycle of researches and developments in organization of the interaction between the organization and external of new products and technologies. Widely spread is a universal tendency to manage such interactions on the basis of the open innovations concept. This requires development of adequate tools for organization and management of domestic aviation systems design with sufficient organizational, financial and spatial flexibility.
The purpose of the work is to identify the factors defining the need for changes in organizational and administrative processes at aviation systems design, and to offer an approach to development and acceleration of design processes, to reduce a new planes development time cycle, and to improve the quality.
The approach which is responsible for the organization and management of proposed design processes, in work, is based on the of System Engineering theory and the theory of complex systems of aircraft industry.
Keywords: organization, V process of design, system engineering, management processes, life cycle model, strategy |