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scientific edition of Bauman MSTU

SCIENCE & EDUCATION

Bauman Moscow State Technical University.   El № FS 77 - 48211.   ISSN 1994-0408

Aeronautical and Rocket Space Engineering

A problem of propellant oscillations in cylindrical and conical tanks
# 11, November 2013
DOI: 10.7463/1113.0623923
M.I. D'yachenko, V.V. Orlov, A.N. Temnov
A problem of fluid oscillations in tanks of space launch vehicles is quite well known and has been investigated extensively during the last decades. This is caused by the fact that the major mass of a liquid-propellant rocket is fluid and its forced motion affects vehicle controllability significantly. In their recent works the authors considered small oscillations in tanks with a propellant intake and with fuel reallocation inside a vehicle. Such problems have arisen due to the purpose of increasing efficiency and output performance of multistage cluster rockets by central stage fueling from side stages of a cluster. The problem of propellant free oscillations in cylindrical and conical tanks was considered, and solutions were presented with boundary conditions on a free surface and the surface of intake that, figuratively speaking, provides resistance to the fluid descent. Eigen-frequencies and Eigen-values of perturbed motion equations with dissipation on boundary surfaces were found. It was shown that slow fluid decent and intake surface boundary conditions may affect both oscillating and damped terms of the solution.
Influence of distribution of specific magnetic flux in thrusters with anode layer on distribution of plasma potential over the accelerator channel
# 11, November 2013
DOI: 10.7463/1113.0620593
M.K. Marahtanov, D.V. Duhopel'nikov, S.G. Ivakhnenko
The authors consider influence of distribution of magnetic field induction on distribution of gas discharge parameters in crossed electric and magnetic fields in the passage of a thruster with an anode layer. The authors proposed a flow model of the electron component, where the flow is perpendicular to the magnetic field, with the use of the specific flux value. The authors also obtained a ratio between distribution of plasma potential over the passage with distribution of the specific flux, and a ratio that allows to determine the position of the low-voltage anode boundary layer. An example of calculating plasma potential distribution over the channel of a thruster with an anode layer, and of determining the position of a low-voltage anode boundary layer was given in this article.
Analysis of design features of large-scale inflatable solar energy concentrators
# 10, October 2013
DOI: 10.7463/1013.0618788
V.V. Leonov, I.S. Jarenov
All these approaches were illustrated by an example of mirror concentrating systems. Special attention was paid to design features of inflatable (pneumatic) solar concentrators and approaches that provide high geometric accuracy of a reflecting surface form when it deploys, fixation and shape stability during operation. It is of particular interest for design, manufacturing and operation of large-sized mirror concentrating systems for high-temperature solar power plants for both ground and space applications. Main design features of inflatable structures are related to the fact that they need to be pressurized for their deployment. But it is also necessary for maintaining (saving) the shape of such structures, which requires presence of structural elements under constant internal inflation pressure and, generally, in a strain state. A number of approaches to minimize problems caused by these design features were discussed, such as use of thermosets, introduction of additional structural elements, etc. Some approaches to design of large-scale space structures were considered in this paper.
Development of mathematical and algorithmic support for determination of internal stresses in thin reflectors made of carbon-epoxy composite during the technological process of manufacturing
# 08, August 2013
DOI: 10.7463/0813.0612095
K.V. Mihailovskii, S.V. Reznik
The main stage of manufacturing precision reflectors is hardening of polymeric matrix which determines the final geometric shape of a product as well as its characteristic. Often, this process takes place in a rigid tool set which restraints changes in the geometric shape. In this connection, during the specified process internal technological stresses appears in the reflector’s material; these stresses could influence precision geometry. This article concerns development of mathematical and algorithmic support for determination of internal stresses and optimization of geometric models in the "reflector – snap" system.
Main approaches to formation of a thermal vacuum test program of precision mirror reflectors of space antennas
# 08, August 2013
DOI: 10.7463/0813.0612062
S.V. Reznik, O.V. Denisov, I.V. Chudnov
An obligatory element of mirror space antennas is a reflector which is a thin-walled shell of a parabolic or hyperbolic form. When a spacecraft enters the area of the Earth's shadow, temperature changes may cause temperature deformations; this may lead to distorting the shape and interfering with radiocommunications. For this reason, design decisions regarding mirror reflectors of space antennas must be confirmed by ground tests. A new method for the thermal vacuum test of a full-scale precision space reflector made of carbon fiber-reinforced plastic was proposed in this work. Stability of the reflector’s shape within a wide range of temperatures was estimated by a contactless method; this method is based on heating of a reflector with a solar radiation simulator in a vacuum chamber with its walls cooled by liquid nitrogen.
Estimation of diamond-like protective coatings resistance to high-energy ion impact
# 08, August 2013
DOI: 10.7463/0813.0605449
Y.B. Volkova, P.A. Mihalev, A.S. Osipkov, E.M. Tomilova, A.V. Fedorchenko
This work deals with the possibility of using diamond-like coatings as protective layers applied to structural elements of a spacecraft. A technique for evaluation of thin coatings resistance to effects of ion radiation with the use of a focused ion beam was described. Results of stability studies of samples of diamond coatings on a substrate made of mono-crystalline silicon using the specified method are presented in this paper. The structure and mechanical properties of the coatings were investigated; the coefficient of diamond-likeness was also determined. It was shown that the resistance of coatings is greater than the resistance of a silicon substrate by not less than 2.5 times. A relation between the resistance of coatings to high-energy ion impact, the degree of diamond-likeness of a coating and its micro-hardness was established.
Numerical modeling of vortex non-steady flow field of viscous gas and acoustic characteristics based on the open source project for calculating the flow around aircraft
# 08, August 2013
DOI: 10.7463/0813.0605410
V.T. Kalugin, A.S. Epihin, M.V. Kraposhin, E.G. Stolyarova
This paper shows the possibility of using the open source CFD software package OpenFOAM and developed methods for calculating unsteady vortex flow fields and acoustic fields in studying the flow around aircraft. Numerical calculations of aerodynamic characteristics of an airbrake mounted on the fuselage of an aircraft were conducted. A hybrid model of turbulence using RANS and LES approaches was defined. Curle’s acoustic analogy was used for calculation. Flow fields of the aircraft and acoustic performance were obtained. Pulsations acting on the tail fin induced by an airbrake were also analyzed. It was determined that pulsations of a lateral force on the fin of an aircraft caused by airbrake was 6 times more than pulsations in absence of the airbrake; and the sound pressure level was more than 50 dB.
Optimization of dynamic characteristics of a ground catapult for minimizing the guide’s length
# 07, July 2013
DOI: 10.7463/0713.0602237
V.A. Sereda
A problem of obtaining the best dynamic performance of a ground launching device (GLD) for starting unmanned aircraft vehicles (UAVs) was formulated in this paper. A well-known catapult construction, allowing to smooth the regressive law of traction, and thereby reduce the boost phase of UAVs, was considered. The author proposed an improved version of GLD; this version is based on the well-known principle of action which is implemented in a flexible transmission. A complex conjugate thermal-gas-dynamical and mechanical model of GLD was developed. With regard to the proposed scheme of the catapult an optimization problem was formulated and optimal characteristics of the cable angles, which allow one to approximate the constant law of overload to high precision, were determined. A number of numerical experiments which helped to obtain the best configuration were carried out on the basis of the model of GLD. The author analyzed physical parameter fields in the cylinder of an expansion engine and their effect on characteristics of the stratum. Dynamic characteristics of the proposed type of GLD were also presented in this paper.
Calculating parameters of flow and acoustic noise for a tandem of cylinders
# 09, September 2013
DOI: 10.7463/0913.0602256
M.V. Kraposhin, I.N. Sibgatullin, S.V. Strijak
The goal of this work is verification of turbulence models and acoustic analogy for flow simulation and calculation of noise for a tandem of cylinders. In the scope of this work numerical results of flow simulation around a tandem of cylinders with different turbulent models were presented. Problem definition and computing methods were also defined. The RANS equations were closed with k-e, k-ω SST, SA turbulence model. Large eddy simulation was based on one sub-grid turbulence model equation. Curle’s acoustic analogy was also used. The computational method is based on the finite method algorithm. The calculation of aerodynamic coefficients of bodies was conducted with different grids and turbulence’s models. Comparison of the obtained results with the experimental results received also by the authors was carried out. On the basis of the obtained results recommendations on calculations of 3D cases could be given.
Problems of minimizing summary characteristic velocity required for maintenance and replenishment of satellite systems at non-coplanar circular orbits
# 09, September 2013
DOI: 10.7463/0913.0598333
A.A. Baranov, D.A. Grishko
This article describes cost estimations of summary characteristic velocity (SCV) required for replenishment of satellite systems at circular and near-circular orbits. TSCV costs optimization for maneuvering is based on using a parking orbit. All possible combinations of values of initial and final orbit parameters were investigated sequentially. The accompanying effects were analyzed; consideration of these effects allows to minimize SCV costs significantly. Analytical relations which determine a number of passive circuits at a parking orbit representing a compromise between time and SCV costs for coplanar flights were found. The obtained results could be used for minimization of temporal and energetic costs while designing and exploiting specified types of satellite systems. In addition, these results are applicable in exploitation of maneuvering space vehicles designed for collecting large-sized space debris.
Monitoring condition of agricultural fields based on prediction of NDVI with the use of multi-spectral and hyper-spectral data from space imagery
# 07, July 2013
DOI: 10.7463/0713.0577991
V.I. Maiorova, A.M. Bannikov, D.A. Grishko, I.S. Jarenov, V.V. Leonov, A.G. Toporkov, A.A. Harlan
Problems of condition monitoring of agricultural fields based on prediction of NDVI dynamics considering climate and atmospheric influence were studied. Different algorithms for preparing initial data were proposed. The research was conducted for the regions of Russia which are notable for different relief, climate and environment. Initial data for simulation were formed by combining the information from the multi-spectral and hyper-spectral space imagery. The conducted mathematical simulation showed a principal opportunity to use Earth observing systems for appropriate short-time predicting of vegetation processes.
Controlling angular movement of a small spacecraft
# 10, October 2013
DOI: 10.7463/0613.0574636
M.V. Palkin, R.A. Petuhov
This authors briefly describe a promising active-passive control system of angular movement of a small spacecraft (by an example of nano-satellites) based on a construction with a gravitational stabiliser and micro-thrusters. Operating modes of the micro-thrusters’ control block were proposed; they were passive mode, initial stabilisation mode, stabilisation and orientation modes. Formulas for determining the required number of micro-thrusters for a small-sized spacecraft in each mode were presented. The main advantages of the proposed active-passive control system of angular movement and applications of a small-sized spacecraft equipped with this system were also described.
Influence of liquefied natural gas composition and functional specifications of storages of launching equipment on rollover phenomenon time
# 02, February 2013
DOI: 10.7463/0213.0552136
N.S. Korolev
The urgency of liquefied natural gas applications as long-range rocket fuel is connected with better characteristics in comparison with rocket kerosene. However, if liquefied natural gas is stored in ground facilities it can be affected by the negative phenomenon called rollover. Studying causes of occurrence of this phenomenon is the primary design task for creating safe storage systems. In this article major factors influencing the start time of the rollover phenomenon are described. The results of the research can be used at designing fueling systems of spaceport ground facilities.
Swaging of extremely thin-walled pipe shells
# 03, March 2013
DOI: 10.7463/0313.0542068
A.A. Shishkin
This article covers problems relative to reduction of extremely thin-walled pipe shells in a rigid die with the use of a tooling shell. This problem was solved by an engineering method of prediction based on the stress equilibrium equation, approximate plasticity condition and the Laplace equation of momentless theory of shells. For calculation of this process, mathematical expressions were obtained and verified experimentally. Experimental researches were conducted with the use of tube shells made of aluminum alloys. It was found that contact friction between an extremely thin-walled shell and a tooling shell influence the process.
Determining constructive-technological parameters of polyamide film-wound pipelines
# 03, March 2013
DOI: 10.7463/0313.0541990
M.A. Komkov, Yu.Z. Bolotin, T.V. Vasil'eva
The authors consider application of polyamide films with fluoroplastic coating for production of film-wound pipelines of aircraft power plants which use cryogenic propellant components. Design problems of multi-layer covers for straight and curvilinear pipelines made of polyamide films were considered; operating and kinematic parameters of spinning and heat treatment of pipelines were determined. The authors proposed a method of connecting the flange shank end of the pipeline with a film cover; specific geometrical dimensions were provided. Results of strength and leakproofness tests of pipe samples made of polyamide film PMF-352 by inner pressure of liquid nitrogen are given in this article. Possibility of their usage in devices that operate on cryogenic fuel is described.
Calculation of loads on truss frames of launching plant units caused by gas-dynamic and wind influence
# 03, March 2013
DOI: 10.7463/0313.0541205
V.A. Zverev, V.V. Lomakin, A.V. Yazykov
 This article describes how to set wind and gas-dynamic loads on truss frames of units of a space rocket launching plant. For automating formation of nodal static loads in finite element software systems, the authors consider a distribution algorithm for non-uniform pressure of wind or the jet of a space rocket propulsion system on rod finite elements. In this paper the authors propose an algorithm for determining load values ​​ for a given cross-section plane of an axisymmetric gas flow. The proposed algorithms and mathematic models can be applied to all units consisting of truss frames. The obtained results were used for calculating bearing assemblies of the launching plant for the space rocket "Soyuz" under the influence of a gas-dynamic jet propulsion of the space rocket "Soyuz-2" at stage 1c.
Simulation of variables in time and rolling load, caused by gas-dynamic influence of a space rocket propulsion pack
# 02, February 2013
DOI: 10.7463/0213.0539497
V.A. Boshnyak, V.A. Zverev, A.V. Ul'yanenkov
The authors consider the problem of parameter representation of gas-dynamic influence of the rocket power-plant jet on structural elements of the launching system for space rockets. Vectors of nodal loads and time dependences are used for modeling this type of influence; these vectors correspond to the rocket position when moving along the calculated trajectory, while time dependences establish a connection between those vectors. The obtained results reflect time and type varying load, which is a distinct feature of this publication. This approach may be applicable for modeling other variables in time and for load point modeling.
Simulation technique of fuel consumption from aircraft fuel tanks in the presence of alternating g-loads
# 02, February 2013
DOI: 10.7463/0213.0533503
A.E. Novikov, G.F. Resh, M.Yu. Ivanov
The aim of this work is to simulate operating process in the aircraft fuel systems, with consideration of external influencing factors. The authors propose a new technique of simulating fuel consumption from fuel tanks during the flight along the trajectory and maneuvering; this technique is based on application of CAD systems and a specially developed finite element FuelTanks solver. The efficiency of this method was demonstrated on a specific example; calculation results were confirmed experimentally. Application domain for the developed method and mathematical software is a wide class of aircraft pneumatic-hydraulic systems along with ground systems which use pressure feed systems. Further development of the work presupposes software product development that follows the whole cycle of creating pneumatic-hydraulic systems from front-end engineering to diagnostic engineering during the operation.
Possible ways to reduce the mass of an aircraft’s rudder control system
# 02, February 2013
DOI: 10.7463/0213.0531715
I.S. Shumilov
Nowadays reduction of the mass of an aircraft’s rudder control system (RCS) still is an important problem for designers, which can be solved by structured design methods or selection of optimal parameters of control system’s different elements. It’s also essential not to degrade the required flight safety and reliability level and meet the demands of airworthiness (AP25), including the influence of the so-called “human factor” on the flight safety. That’s why, to reduce the mass of MCS, one can try to reduce the mass of each element; one has to deal with working levers and control-loading devices, remote signal transmission, rudder gears, energy supply systems and mass and geometry optimization system for several elements of RCS. This article provides analyses and necessary recommendations for designers on every of listed directions.
Influence of interaction of gas masses on efficiency of intermittent-cycle engines
# 01, January 2013
DOI: 10.7463/0113.0522954
D.S. Khantalin
 The article presents results of numerical investigation of mass interaction influence on propulsion performance characteristics of a spherical resonator of an intermittent-cycle engine. Analysis of the resonator’s flow features compared to the theory of unsteady outflow was conducted. Main attention was paid to research of influence of joining cyclic and external masses on traction performance. A problem of improving the numerical method for fast processes was formulated while comparing calculation data with experimental results. Impact on propulsion performance characteristics of mechanical and geometrical relations, intensification of the process of joining masses and elasticity of high-temperature gas was also investigated. On the basis of the obtained results the need for more integrated studies of non-stationary effects of the oscillatory pulsing process was indicated.
 
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