One of the problems that has been solved for more than 80 years is the dynamic behavior both during the development of a rocket engine and during operation, these are oscillations that occur in the combustion chamber. Gas vibrations and mechanical vibrations of the rocket engine elements can cause vibration loads, which, under certain conditions, leads to resonance phenomena. This can cause engine failures. An analysis of the behavior of a rocket engine as a dynamic system with an assessment of frequency interactions over the entire time of its operation has not been completely resolved today. Various options for studying the dynamic behavior of a rocket engine, algorithms for determining natural oscillation frequencies are considered. The analysis of existing approaches for solving the problem of determining the dynamic behavior of the rocket engine was carried out. In various works, the mechanical vibrations of the engine housing or its elements, such as a sliding nozzle, are calculated using various methods. In a number of works, the structure is considered as a model of discrete masses, where the elements are connected through the stiffness and viscosity coefficients. In other cases, fluctuations of the gas flow during combustion in the combustion chamber are considered, methods of numerical simulation of the process are developed that take into account the features of vortex formation and instability of the gas flow, as well as dependence on the shape of the charge. However, the joint problem has not been solved; in the presented works, the mutual influence of the vibrations of the rocket engine case with the fuel and gas flow during operation is not considered. To get a complete picture of the dynamic loads experienced in a solid propellant rocket engine, this interaction must be taken into account.

Keywords: natural frequencies, vibrations, resonance, gas flow, amplitude, deformation, shell, dissipation, acoustic instability, pressure.

Daniil A. Mironov (Perm, Russian Federation) – PhD Student of the Department of Rocket and Space Engineering and Energy Systems, Perm National Research Polytechnic University (29, Komsomolsky av., 614990, Perm), design engineer, Scientific and Production Association «Iskra» (28, Akademika Vedeneeva str., 614038, Perm, e-mail: daniil284@gmail.com).

Aleksey F. Salnikov (Perm, Russian Federation) – Doctor of Technical Sciences, Professor of the Department of Rocket and Space Engineering and Energy Systems, Perm National Research Polytechnic University
(29, Komsomolsky av., 614990, Perm, e-mail: afsalnikov_1@mail. ru).

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Axisymmetric aircraft can be adversely affected by asymmetries of various types, such as mass asymmetry, aerodynamic and combinations thereof. This influence can manifest itself in off-design modes of motion, increased overloads, and trajectory deviation. On the other hand, the deliberate introduction of asymmetry, in particular mass asymmetry, can compensate for the negative impact of both mass-inertial and aerodynamic asymmetries, and will also allow the creation of aerodynamic forces for spatial maneuvering. This can be implemented using the center of mass displacement system installed on board the product.

The paper presents the results of a study of the motion of an aircraft with a center-of-mass displacement system. This system is implemented in the form of a balancing load fixed on a movable platform with a drive based on a mechanism with parallel kinematics of the hexapod type. The considered design generally provides 6 degrees of freedom of the balancer – three linear movements of the center of mass relative to the aircraft frame and three angles of rotation of the balancer around its center of mass. This allows displacement the center of mass of the aircraft and compensating for three centrifugal moments. A mathematical model for determining the mass-inertial characteristics of an aircraft is presented, describing the structure as a system of two solids: the body is a balancer. A scheme is proposed for changing the position of the balancer to displacement the center of mass of the system and compensate for centrifugal moments. The case of a transverse displacement of the center of mass of the aircraft along the axis of the coordinate system associated with the aircraft frame according to the law, allows the aircraft to be installed in the equilibrium position at the required angle of attack is considered. The mass-inertial characteristics of the aircraft over the entire period of time of the displacement of the center of mass are determined. The inverse kinematics problem for determining the lengths of the rods of a movable platform is solved.

Keywords: axisymmetric aircraft, asymmetry, angle of attack, displacement of the center of mass, motion model, mass-inertial characteristics, balancing, mechanism with parallel kinematics, hexapod, inversekinematicsproblem.

Evgenii A. Mikhailov (Chelyabinsk, Russian Federation) – Postgraduate Student of the Department “Aircraft and Rockets”, South Ural State University (76, Lenin av., 454080, Chelyabinsk, e-mail: evgeniy-mihaylov-09@mail.ru).

Viktor B. Fedorov (Chelyabinsk, Russian Federation) – Ph. D. in Technical Sciences, Deputy Head of Department “Aircraft and Rockets”, South Ural State University (76, Lenin av., 454080, Chelyabinsk, e-mail: vbf64@mail.ru).

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A modern gas turbine engine must meet a large list of requirements that are included in the parameters, resource and performance indicators. To increase the service life of a gas turbine engine at elevated temperatures of the gas flow, it is expendable to use thermal barrier protection on explosive structural materials. Cyclic tests of materials and thermal barrier coatings of gas turbine engines at temperatures above 1500 ºС are proposed to be carried out on a stand in which a hot gas flow is generated by an air-methane burner. In order to reduce the emission standards for nitrogen and carbon oxides, it is necessary to develop and use in stationary gas turbine engines fundamentally new technologies for organizing combustion and, as a result, designs of combustion chambers.

From a detailed analysis of the current requirements, it follows that the newly designed low-emission combustion chamber for advanced gas turbine engines and installations should be accompanied by an increase in gas temperature by 200–300 K, an increase in the durability of the flame tube by 3–4 times, with a twofold decrease in the proportion of air for cooling the walls, a twofold or more reduction in the emission of harmful substances.

In this article, heat-resistant coatings of structural elements of gas turbines are considered. The concepts of low-emission fuel combustion are described by organizing the working process according to the "DLE" - Dry Low Emission scheme. As an alternative method for organizing low-emission combustion, stoichiometric combustion is proposed, which also makes it possible to provide the required temperature of the gas jet. A review of low-emission combustion chambers has been carried out. The existing methods of cooling the combustion chambers of gas turbine and liquid rocket engines are described. The analysis of the collected information made it possible to determine the concept of designing a high-temperature air-methane burner.

Keywords: low-emission combustion chamber, metal coating, ceramic coating, low-emission combustion, cooling system, fuel-air mixture, gas turbine engine, liquid-propellant rocket engine, flame tube, microturbine, recuperator, combustion products.

Ekaterina V. Kharlina (Perm, Russian Federation) – Postgraduate Student, Department of Rocket and Space Technology, Perm National Research Polytechnic University (29, Komsomolsky av., 614990, Perm, e-mail: katerinka_bev@mail.ru).

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Increased vibrations of a gas turbine engine reduce the reliability and overall service life of the engine. The main reason for the appearance of increased vibrations is the dynamic imbalance (dynamic imbalance) of one or more engine rotors. Dynamic unbalance in its turn is a cumulative manifestation of static and moment unbalance of the rotor.

One of the reasons for the appearance of unacceptable values of rotor imbalances is the imperfection of the geometric parameters of the parts, that is, the manufacturing errors of these parts. Despite the fact that at present there are strict requirements for the accuracy of manufacturing parts of a gas turbine engine, it is impossible to manufacture a part without errors.

When joining several rotors, the summing errors in the manufacture of parts may lead to a shift in the center of mass of the rotors, as well as to a misalignment of their axes, which in turn leads to an increase in the imbalances of the assembled rotor. As a result of the vibration of the assembled engine significantly exceed the permissible.

The problem of the influence of errors in the manufacture of parts on the unbalances of the gas turbine engine rotor during its assembly is analyzed. A review analysis of the methods for solving this problem, presented in modern scientific papers, is carried out. A technique for 3D modeling of the GTE rotor assembly is given, taking into account the beat vectors to predict the static and moment imbalances of the assembled rotor. Based on the simulation results, the displacements of the center of mass of the analyzed rotor and the distortions of its axis are calculated for different positions of the beat vectors. The conclusion is made about the expediency of applying the considered methodology in the design of modern gas turbine engine.

Keywords: gas turbine engine, vibration, imbalance, rotor, detail, assembly, end and radial runouts, manufacturing error, assembly, 3D modeling.

Daniil G. Sainakov (Perm, Russian Federation) – Vibration Research Engineer, UEC-Aviadvigatel
(93, Komsomolsky av., 614010, Perm, e-mail: sainakov-dg@avid.ru).

Ilya L. Budnickiy (Perm, Russian Federation) – Vibration Research Engineer, UEC-Aviadvigatel
(93, Komsomolsky av., 614010, Perm, e-mail: budnickiy-il@avid.ru).

Artem P. Kozlov (Perm, Russian Federation) – Head of Vibration Research Department, UEC-Aviadvigatel (93, Komsomolsky av., 614010, Perm, e-mail: kozlov-ap@avid.ru).

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15. Ryzhenkov V.M., Tikhomirov V.V. Pogreshnosti balansirovki rotorov gazoturbinnykh dvigateley [Balancing errors of rotors of gas turbine engines]. Bulletin of the Voronezh State Technical University, vol. 15, 2019, no.2, pp. 145-150.

When milling the profile of the flow path of the vanes of a gas turbine engine on multi-axis machines, a technological scheme of transverse line shaping is used, according to which the vane is rotated around its own axis and processed with a tool with a spherical working surface that performs rotation and interpolated axial movement. The required indicators of the surface quality of the vane airfoil profile (profile accuracy and surface roughness) are provided by assigning a combination of controlled parameters of the milling mode. However, at present there are no recommendations on the calculation and assignment of a combination of controlled parameters for the milling of complex-profile surfaces, which is the profile of the flow path of the gas turbine engine compressor vanes. The accuracy of the profile of the vane feather for each line and the angle of its rotation will be determined by the value of the vane deformations, which should not exceed the tolerance for its manufacture. From the analysis of geometric relationships in the contact zone of the mill with a spherical working surface and a curved profile of the flow path of the vane, dependencies were established for calculating the component of the milling force and its projection on the Y axis, as well as the effective diameter of the mill necessary to calculate the total deformation of the vane. The methodology is described and analytical expressions are obtained for calculating and assigning a combination of controlled parameters of the milling mode that provide the required accuracy of the vane airfoil profile when developing a control program and milling a vane on a Computer Numerical Control machines.

Keywords: flow path, vane profile milling, mill effective diameter, cutting forces, contact arc length, parameters of the transverse line milling mode.

Valentin I. Svirshchev (Perm, Russian Federation) – Doctor of Technical Sciences, Professor, Department “Innovative technologies of mechanical engineering”, Perm National Research Polytechnic University (29, Komsomolsky av., 614990, Perm, e-mail: svirshchev@pstu.ru).

Stepan V. Tarasov (Perm, Russian Federation) – C.Sc in Technical Sciences, Associate Professor, Department “Innovative technologies of mechanical engineering”, Perm National Research Polytechnic University
(29, Komsomolsky av., 614990, Perm, e-mail: tarasovsv100@mail.ru).

Vladislav V. Merezhnikov (Perm, Russian Federation) – Post Graduate Student, Department “Innovative technologies of mechanical engineering”, Perm National Research Polytechnic University (29, Komsomolsky av., 614990, Perm, e-mail: merejnikov.v@yandex.ru).

1. Krymov V.V. Yeliseyev Yu.S., Zudin K.I. Proizvodstvo lopatok gazoturbinnykh dvigateley [Production of blades for gas turbine engines]. Moscow: Mashinostroyeniye, 2002, 376 p.

2. Poletayev V.A. Tekhnologiya avtomatizirovannogo proizvodstva lopatok gazoturbinnykh dvigateley [Technology of automated production of blades for gas turbine engines]. Moscow: Mashinostroyeniye, 2006, 256 p.

3. V.I. Svirshchev, I.G. Bashkatov, D.V. Okoneshnikov, Yu.N. Stepanov, S.V. Tsypkov. Sposob strochnogo frezerovaniya pera lopatki gazoturbinnogo dvigatelya [Method for line milling of a blade feather of a gas turbine engine]. Patent 2354508, MKN V23S3/18 Rossiyskaya Federatsiya., №2007124229/02; 5 p.

4. Sulima A.M., Noskov A.A., Serebrennikov G.Z. Osnovnyye tekhnologii proizvodstva gazoturbinnykh dvigateley [Main technologies for the production of gas turbine engines]. Moscow: Mashinostroyeniye. 1996, 480 p.

5. Rakhmarova M.S., Mirer YA.G. Vliyaniye tekhnologicheskikh faktorov na nadezhnost lopatok gazovykh turbin [Influence of technological factors on the reliability of gas turbine blades]. Moscow: Mashinostroyeniye, 1966, 223 p.

6. Semenchenko I.V., Mirer Ya.G. Povysheniye nadezhnosti lopatok gazoturbinnykh dvigateley [Improving the reliability of gas turbine engine blades]. Moscow: Mashinostroyeniye, 1977, 160 p.

7. Suslov A.G. Tekhnologicheskoye obespecheniye parametrov sostoyaniya poverkhnostnogo sloya detaley [Technological support of the state parameters of the surface layer of parts]. Moscow: Mashinostroyeniye, 1987, 208 p.

8. V.F. Bezyazychnyy, V.N. Krykhov, V.A. Poletayev, etc. Avtomatizatsiya tekhnologii izgotovleniya gazoturbinnykh aviatsionnykh dvigateley [Automation of manufacturing technology for gas turbine aircraft engines]. Moscow: Mashinostroyeniye, 2005, 566 p.

9. Yu. S. Yeliseyev, etc. Tekhnologiya proizvodstva aviatsionnykh gazoturbinnykh dvigateley: uchebnoye posobiye dlya vuzov [Production Technology of Aircraft Gas Turbine Engines: textbook for universities]. Moscow: Mashinostroyeniye, 2003, 511 p.

10. Svirshchev V.I., Tarasov S.V., Tukachev D.V., Cherepanov S.E. Sposob strochnogo frezerovaniya pera lopatki gazoturbinnogo dvigatelya na mnogokoordinatnykh stankakh s CHPU [The method of line milling of the blade feather of a gas turbine engine on multi-axis CNC machines]. Patent 2607880 Rossiyskaya Federatsiya: MKN V23S3/18, № 2015124625, 5 p.

11. G.M. Itskovich, A.I. Vinokurov, L.S. Minin and etc. Rukovodstvo k resheniyu zadach po soprotivleniyu materialov [A Guide to Solving Strength of Materials Problems]. Moscow: Vysshaya shkola, 1970, 544 p.

12. Svirshchёv V.I., Tarasov S.V., Merezhnikov V.V. Normativnyye geometricheskiye parametry secheniy protochnoy chasti kompressornykh lopatok gazoturbinnogo dvigatelya, neobkhodimyye dlya prognozirovaniya i tekhnologicheskogo obespecheniya pokazateley kachestva [Normative geometric parameters of the sections of the flow part of the compressor blades of a gas turbine engine, necessary for forecasting and technological support of quality indicators]. PNRPU Aerospace Engineering Bulletin, 2017, no. 49, pp.103-117.

13. Merezhnikov V.V. Metodologiya i raschetnyye znacheniya radiusov spinki i koryta kompressornykh lopatok GTD dlya obespecheniya tochnosti protochnoy chasti pri poperechnom strochnom frezerovanii na stankakh s CHPU [Methodology and calculated values of the radii of the back and trough of the GTE compressor blades to ensure the accuracy of the flow path during transverse line milling on CNC machines]. Collection of articles of the International Scientific and Practical Conference «Nauchnyye issledovaniya po prioritetnym napravleniyam dlya sozdaniya innovatsionnykh tekhnologiy», Kirov, 2022, pp. 96-99.

14. G. Korn, T. Korn, Spravochnik po matematike dlya nauchnykh rabotnikov i inzhenerov [Handbook of mathematics for scientists and engineers]. Moscow: Nauka, 1984, 831 p.

15. Ya. L. Gurevich, M.V. Gorokhov, V.I. Zakharov and etc. Rezhimy rezaniya trudnoobrabatyvayemykh materialov: Spravochnik [Cutting Conditions for Difficult-to-Machine Materials: A Handbook]. Moscow: Mashinostroyeniye, 1968, ed. 2, 240 p.

16. A.M. Dalskiy, A.G. Suslov, A.G. Kosilova, R.K. Meshcheryakov. Spravochnik tekhnologa-mashi­nostroitelya [Handbook of the technologist-machine builder]. Moscow: Mashinostroyeniye-1, 2003, vol. 2, 944 p.

17. Merezhnikov V.V., Svirshchev V.I. Analiticheskoye opisaniye uprugikh deformatsiy lopatki kak dvukhopornoy balki ot poperechnykh normalnykh sostavlyayushchikh sil rezaniya pri strochnom frezerovanii [Analytical description of elastic deformations of a blade as a two-bearing beam from transverse normal components of cutting forces during line milling]. Collection of articles of the International Scientific and Practical Conference «Aktualnyye problemy teorii, metodologii i praktiki nauchnoy deyatelnosti», Ufa, 2022, pp. 74-78.

18. Merezhnikov V.V., Svirshchev V.I. Opredeleniye funktsionalnoy zavisimosti fakticheskogo znacheniya plecha prilozheniya normalnoy sostavlyayushchey sily frezerovaniya otnositelno osi vrashcheniya lopatki pri poputnom poperechnom strochnom frezerovanii protochnoy chasti kompressornykh lopatok GTD na stankakh s CHPU [Determination of the functional dependence of the actual value of the shoulder of the application of the normal component of the milling force relative to the axis of rotation of the blade during associated transverse line milling of the flow path of the GTE compressor blades on CNC machines]. Innovative scientific research, Ufa, №2-1(16), 2022, pp. 23-37.

19. Merezhnikov V.V. Analiz geometricheskikh svyazey v zone kontakta frezy so sfericheskoy rabochey poverkhnost′yu i krivolineynym profilem protochnoy chasti kompressornykh lopatok GTD i opredeleniye funktsionalnoy zavisimosti dlya raschetnogo znacheniya plecha prilozheniya normalnoy sostavlyayushchey sily frezerovaniya pri vstrechnom poperechnom strochnom frezerovanii na stankakh s CHPU [Analysis of geometric relationships in the contact zone of the cutter with a spherical working surface and a curvilinear profile of the flow path of the GTE compressor blades and determination of the functional dependence for the calculated value of the shoulder for applying the normal component of the milling force during counter-cross line milling on CNC machines]. Collection of articles of the IV International Scientific and Practical Conference «Aktualnyye nauchnyye issledovaniya», Penza: MTSNS «Nauka i prosveshcheniye», 2022, pp. 101-109.

The experimental research of the peripheral unevenness of air-blast atomizer with different fuel sprayers has been conducted on a hydraulic stand. The experimental research of fuel atomizers based on laser anemometer’s readings has been conducted. Parameters of atomization characteristics and circular velocity have been analyzed. Based of those findings and relevant research information, hypotheses have been made that is capable to properly describe experimental results. Basic guidance’s to future investigations has been given.

Keywords: air-blast atomizer, liquid film, fuel jet, diameter of fuel drop, spray irregularity.

Ilya M. Aleksandrov (Perm, Russian Federation) – Mechanical engineer, Department of Combustion Chambers, UEC-Aviadvigatel (93, Komsomolsky av., 614990, Perm, e-mail: aleksandrov-im@avid.ru).

Danil A. Krinitsyn (Perm, Russian Federation) – Mechanical engineer, Department of Combustion Chambers, UEC-Aviadvigatel (93, Komsomolsky av., 614990, Perm, e-mail: krinitsyn-da@avid.ru).

Aleksey M. Sipatov (Perm, Russian Federation) – Doctor in Technical Sciences, Head of Department, Department of Combustion Chambers, UEC-Aviadvigatel (93, Komsomolsky av., 614990, Perm, e-mail: sipatov@avid.ru).

1. Aviatsionniye pravila. Chast 34. Okhrana okruzhaushcey sredy. Emissiya zagryaznzyzushih veshestv aviatsionnimy dvigatelyami. Normy I ispitanya [Aviation rules. Part 34. Environmental protection. Emissions of pollutants from aircraft engines. Norms and tests]. Moscow: Aviaizdat, 2003, 84 p. URL: http:/­www.aviadocs.net/docs/2003_AP_ch34.pdf (Date of access: 07/15/2022).

2. Lefebvre A. Processes in the combustion chambers of gas turbine engines. McGraw-Hill Book Company, 1986, 566.

3. Launder B.E., Spalding D.B. The numerical computation of turbulent flows // Comput. Method. Appl. M, 1974, Vol. 4, No. 2, pp. 269-289.

4. Inozemtsev A.A., Nikhamkin M.A., Sandratskiy M.L. Osnovy construirovaniya aviatsionnyh dvigateley I energeticheskih ustanovok [Fundamentals of designing aircraft engines and power plants]. Moscow: Mashinostroyeniye, 2008, vol. 2, 365 p.

5. Dityakin Yu.F., Klyachko L.A., Novikov B.V., Yagodkin V.I. Raspylivanie zhidkostey [Spraying liquids]. Moscow: Mashinostroyeniye, 1977, 208 p.

6. GOST 10227-86. Topliva dlya raketnyh dvigateley. Tecknicheskiye uslovia [Fuel for jet engines. Specifications.]. Мoscow, 2008, 14 p.

7. OST 1.76118-71. Stendy prolivochnye dlya contrlya gidravlicheskogo soprotivlenya I propusknoy sposobnosty. Raschet na tochnost [Stands pouring for control of hydraulic resistance and throughput. Calculation for accuracy]. Ufa: National Institute of Aviation Technology, 1971, 137 p.

8. Chelebyan O.G., Vasilyev A.Y., Sviridenkov A.A., Loginova A.A. «Researches of two-phase stream by methods of registration of fluorescence of drops of liquid and Shadowgraph» // Journal of Physics: Conference Series, no. 1421(1), art. 012009.

9. Chelebyan O.G., Siluyanova M.V., Vasilyev A.Yu., Loginova A.A., Maslov V.P., Zakharov D.L. Graniysy primeneniya metoda tenevoy anemometrii tchastits dlya issledovania dvuhfaznyh potokov [Limits of application of the method of shadow anemometry of particles for the study of two-phase flows]. Aerospace MAI Journal, 2017, vol. 24, no.1, p 14-18.

10. A.M. Sipatov, S.A. Karabasov, L.Yu. Gomzikov, T.V. Abramchuk and G.N. Semakov. Primeneniye metodov trehmernogo modelirovanya pri konstruirovanii pnevmaticheskih forsunok [Application of 3D modeling methods in the design of pneumatic nozzles]. Computational continuum mechanics, 2013, vol. 6, no. 3, pp. 346-353.

11. Batalov V.G., Kolesnichenko I.V., Stepanov R.A., Sukhanovskii A.N. Primenenie polevykh metodov izmerenii dlya issledovaniya dvukhfaznykh potokov [Application of field measurement methods for the study of two-phase flows]. Vestnik permskogo universiteta. Seriya: Matematika. Mekhanika. Informatika, 2011, no. 5 (9), pp. 21-25.

12. Batalov V.G., Kolesnichenko I.V., Sukhanovskii A.N. Izmerenie razmerov chastits v fakele forsunki metodom IPI [Particle size measurement in the nozzle jet by the IPI method]. Proceedings of the All-Russian Conference of Young Scientists (with international participation) «Neravnovesnye protsessy v sploshnykh sredakh», Perm, 26-27 noyember 2010, pp. 27-30.

13. Batalov V.G., Sukhanovskii A.N. Izmerenie kharakteristik dvukhfaznogo potoka v fakele forsunki metodami PIV i IPI [Measurement of characteristics of two-phase flow in the nozzle jet using PIV and IPI methods]. XI International Scientific and Technical Conference "Optical Methods for Investigating Flows". Moscow: National Research University "Moscow Power Engineering Institute", 2011, no. 61. 6 p.

14. Tokarev M.P., Makarovich D.M., Bilskiy A.V. Adaptivnye algoritmy obrabotki izobrazheniy chastits dlya rascheta mgnovennyh polei skorostey [Adaptive Particle Image Processing Algorithms for Calculating Instantaneous Velocity Fields]. Computational Technologies, Vol.12, no.3, 2007, pp. 109-131.

To reliably determine the characteristics of cooled turbines in CFD simulation, it is necessary to take into account the interaction of film cooling jets with the main flow. For a correct description of such processes, it is necessary to refine the grid of finite volume mesh, which requires significant resources for the calculation and high qualification of the engineer. An attempt to simplify the model reduces the reliability of the results obtained. There are no systematic recommendations in the available publications on the choice of settings for numerical models of film-cooled turbines.

This paper presents results aimed at finding optimal settings for numerical models that allow accurate and cost-effective simulation of the workflow in cooled film-cooled turbines. As a result, practical recommendations were obtained on the choice of mesh parameters and turbulence models for such problems.

– the value of y+ is not more than 2;

– number of elements in the near-wall layer: at least 20;

– cell growth factor in the near-wall layer: not less than 1.2.

The use of these recommendations will make it possible to obtain results close to real ones while reducing the required time and computational costs.

Keywords: axial turbine, cooling, nozzle blade, film cooling, numerical modelling, accuracy, verification, accuracy estimation, statistic criteria.

Andrey A. Volkov (Samara, Russian Federation) – p.h.d. student, Department of Engine Theory, Samara National Research University (34, Moskovskoye shosse, 443086, Samara, e-mail: a44rey@gmail.com).

Grigoriy M. Popov (Samara, Russian Federation) – CSc in Technical Sciences, associate professor Department of Engine Theory, Samara National Research University (34, Moskovskoye shosse, 443086, Samara, e-mail: grishatty@gmail.com).

Oleg V. Baturin (Samara, Russian Federation) – CSc in Technical Sciences, associate professor Department of Engine Theory, Samara National Research University (34, Moskovskoye shosse, 443086, Samara, e-mail oleg.v.baturin@gmail.com).

Vasiliy M. Zubanov (Samara, Russian Federation) – CSc in Technical Sciences, associate professor Department of Engine Theory, Samara National Research University (34, Moskovskoye shosse, 443086, Samara, e-mail waskes91@gmail.com).

Sergey A. Melnikov (Samara, Russian Federation) – engineer, Scientific and Educational Center of Gas Dynamic Research, Department of Engine Theory, Samara National Research University (34, Moskovskoye shosse, 443086, Samara, e-mail: m.asergey196@gmail.com).

1. Inozemcev A.A., Nihamkin M.A., Sandrackii V.L. Osnovy konstruirovanija aviacionnyh dvigatelej i jenergeticheskih ustanovok [Fundamentals of designing aircraft engines and power plants]. Moscow: Mashinostroenie, 2008, 207 р.

2. Ho K., Liu J.S., Elliott T., et al. Coupled Heat Transfer Analysis for Gas Turbine Film-Cooled Blade, Proceedings of the ASME Turbo Expo 2016: Turbomachinery Technical Conference and Exposition. Volume 5A: Heat Transfer., 2016, рaper No: GT2016-56688, V05AT10A003. URL: DOI.org/10.1115/GT2016-56688 (Accessed: 09/01/22)

3. Ke Z., Wang J. Coupled heat transfer simulations of pulsed film cooling on an entire turbine vane. Applied Thermal Engineering, 2016, vol. 109, pp. 600-609.

4. Insinna M, Griffini D, Salvadori S., et al. Coupled Heat Transfer Analysis of a Film Cooled High-Pressure Turbine Vane Under Realistic Combustor Exit Flow Conditions. Proceedings of the ASME Turbo Expo 2014: Turbine Technical Conference and Exposition. Volume 5A: Heat Transfer, 2014, рaper No: GT2014-25280, V05AT11A007. URL: DOI.org/10.1115/GT2014-25280 (Accessed: 09/01/22)

5. Wróblewski W. Numerical evaluation of the blade cooling for the supercritical steam turbine. Applied Thermal Engineering, 2013, № 51, рр. 953–962.

6. Bonini A., Andreini A., Carcasci C., et al. Coupled Heat Transfer Calculations on GT Rotor Blade for Industrial Applications: Part I–Equivalent Internal Fluid Network Setup and Procedure Description. Proceedings of the ASME Turbo Expo 2012: Turbine Technical Conference and Exposition. Volume 4: Heat Transfer, Parts A and B, 2012, рaper No: GT2012-69846, рр.669–679. URL: DOI.org/10.1115/GT2012-69846 (Accessed: 03.09.22)

7. Shevchenko I.V., Rogalev N., Rogalev A., et al. Verification of Thermal Models of Internally Cooled Gas Turbine Blades. International Journal of Rotating Machinery, 2018, Article ID 6780137, 10 p. DOI: 10.1155/2018/6780137

8. Duchaine F., Corpron А., Pons L. Development and assessment of a coupled strategy for coupled heat transfer with Large Eddy Simulation: Application to a cooled turbine blade. International Journal of Heat and Fluid Flow, 2009, no. 30, рр. 1129-1141. DOI:10.1016/J.IJHEATFLUIDFLOW.2009.07.004

9. Hylton L.D., Mihelc M.S., Turner E.R., et al. Analytical and Experimental Evaluation of the Heat Transfer Distribution over the Surfaces of Turbine Vanes // NASA technical report: NASA-CR-168015, 1983, 225 p.

10. Popov G., Matveev V., Baturin O., et al. Selection of Parameters for Blade-To-blade Finite-volume Mesh for CFD Simulation of Axial Turbines. MATEC Web of Conferences, 2018, Vol. 220, No. 03003(2018), 8 p. DOI:10.1051/matecconf/201822003003

The paper considers the possibility of switching the existing AL-31ST gas turbine unit from methane to hydrogen fuel. The calculation and comparison of the main thermodynamic parameters of a gas turbine installation on various types of fuel is carried out. The thermodynamic characteristics of the hydrogen plant are calculated while maintaining the gas temperature at the inlet to the high-pressure turbine. The use of hydrogen in the form of fuel will increase the efficiency of the installation, as well as reduce fuel consumption. Replacing methane with hydrogen allows you to get zero emissions of carbon-containing substances.

Keywords: gas turbine plant, hydrogen, methane, thermodynamic parameters, power, efficiency, degree of reduction of total pressure, excess air coefficient, fuel consumption, emission.

Yurii Yu. Frolov (Perm, Russian Federation) – PhD Student, Department “Rocket and Space Engineering and Power Generating Systems”, Perm National Research Polytechnic University (29, Komsomolsky av., 614990, Perm, e-mail: frolovyy@yandex.ru).

Viktor A. Medvedev (Perm, Russian Federation) – PhD Student, Department “Rocket and Space Engineering and Power Generating Systems”, Perm National Research Polytechnic University (29, Komsomolsky av., 614990, Perm, e-mail: vitek_96-04@mail.ru).

Mikhail Yu. Khramtsov (Perm, Russian Federation) – Head of the Educational Laboratory, PhD student, Department “Rocket and Space Engineering and Power Generating Systems”, Perm National Research Polytechnic University (29, Komsomolsky av., 614990, Perm, e-mail: hramtsovm@yandex.ru).

Roman V. Bulbovich (Perm, Russian Federation) – Doctor of Technical Sciences, Professor, Department “Rocket and Space Engineering and Power Generating Systems”, Perm National Research Polytechnic University (29, Komsomolsky av., 614990, Perm, e-mail: bulbovich@pstu.ru).

1. Chiesa P., Lozza G., Mazzocchi L. Using Hydrogen as Gas Turbine Fuel // Journal of Engineering for Gas Turbines and Power-transactions of The Asme – J ENG GAS TURB POWER-T ASME (2005), Vol.127, pp. 73-80. DOI:10.1115/1.1787513.

2. Baklanov A.V. Vozmozhnost ispolzovaniya metano-vodorodnogo topliva v konvertirovannykh gazoturbinnykh dvigatelyakh dlya energeticheskikh ustanovok [The possibility of using methane-hydrogen fuel in converted gas turbine engines for power plants]. Siberian Aerospace Journal, 2021, Vol. 22, No. 1, pp. 82-93.

3. Filimonov A.G., Filimonova A.A., Chichirova N.D., Chichirov A.A. Globalnoye energeticheskoye obyedineniye: nov·yye vozmozhnosti vodorodnykh tekhnologiy [Global Energy Association: new possibilities of hydrogen technologies]. Power engineering: research, equipment, technology, 2021, Vol. 23, No. 2, pp. 3-13.

4. Kozlov V.V., Grek G.R., Litvinenko Yu.A., Shmakov A.G., Vikhorev V.V. Diffuzionnoye goreniye krugloy mikrostrui vodoroda pri do- i sverkhzvukovoy skorosti istecheniya iz sopla [Diffusion combustion of a circular microjet of hydrogen at pre- and supersonic velocity of discharge from the nozzle]. Siberian Physical Journal, 2018, Vol.13, No. 2, pp. 37-52.

5. Shmakov A.G., Grek G.R., Kozlov V.V., Kozlov G.V., Litvinenko Yu.A. Eksperimental'noye issledovaniye diffuzionnogo goreniya vysokoskorostnoy krugloy mikrostrui vodoroda. Chast 1. Prisoyedinennoye plamya, dozvukovoye techeniye [Experimental study of diffusion gorenje high-speed circular microjet hydrogen. Part 1. Attached flame, subsonic flow]. Siberian Physical Journal, 2017, Vol. 12, No. 2, pp. 28-45.

6. Kozlov V.V., Grek G.R., Korobeinichev O.P., Litvinenko Yu.A., Shmakov A.G. Osobennosti goreniya vodoroda v krugloy i ploskoy mikrostruye v poperechnom akusticheskom pole i ikh sravneniye s rezultatami goreniya propana v tekh zhe usloviyakh [Features of hydrogen combustion in a round and flat microjet in a transverse acoustic gorenje the field and their comparison with the results of gorenje propane under the same conditions]. Siberian Physical Journal, 2014, Vol. 9, is. 1, pp. 79-86.

7. Kozlov V.V., Shmakov A.G., Grek G.R., Kozlov G.V., Litvinenko Yu.A. Yavleniye zapiraniya mikrosopla pri diffuzionnom gorenii vodoroda [The phenomenon of microsoplasmic locking during diffusive gorenje hydrogen]. DOKLADY AKADEMII NAUK, 2018, Vol. 480, No. 1, pp. 34-39.

8. Shmakov A.G., Kozlov V.V., Litvinenko M.V., Litvinenko Yu.A. Izucheniye predelov ustoychivogo goreniya diffuzionnogo plameni mikrostrui vodoroda, istekayushchey iz kruglogo mikrosopla, pri vvedenii v vodorod ili vozdukh inertnykh i reagiruyushchikh gazov [Study of the limits of stable combustion of a diffusion flame of a hydrogen microjet flowing from a round microsoplane when inert and reacting gases are introduced into hydrogen or air]. Siberian Physical Journal, 2019, Vol. 14, No. 3, pp. 64-75.

9. Volchkov E.P., Lukashov V.V. Eksperimentalnoye issledovaniye kharakteristik laminarnogo pogranichnogo sloya pri gorenii v nёm vodoroda [Experimental investigation of the characteristics of a laminar boundary layer during the combustion of hydrogen in it]. Combustion, Explosion and Shock Waves, 2012, Vol. 48, No. 4, pp. 3-10.

10. Li Y., Zhang X., Wang Y. Experimental study on the combustion characteristics of premixed methane-hydrogen-air mixtures in a spherical closed chamber // Fuel, 2021, Volume 299, pp. 20885-20895.

11. Zhang X., Yang Z., Zuang X., Wang X., Pan Y., Zhou X., Combustion enhancement and inhibition of hydrogen-doped methane flame by HFC-227ea // International Journal of Hydrogen Energy, 2021, Volume 46, Issue 41, pp. 21704-21714.

12. Beteva A.S., Kiverin A.D., Medvedev S.P., Yakovenko I.S. Chislennoye modelirovaniye rezhimov turbulentnogo goreniya vodoroda vblizi bednogo predela [Numerical modeling of turbulent hydrogen combustion regimes near the poor limit]. Russian Journal of Physical Chemistry B: Focus on Physics, 2020, vol.39, No. 12, p.17-23.

13. Gorev A. O kontsentratsionnykh predelakh rasprostraneniya plameni v sisteme vodorod-vozdukh [On the concentration limits of flame propagation in the hydrogen-air system]. Pozharovzryvobezopasnost, 2011, vol.20, No. 12, pp. 23-26.

14. O.V. Komarov, V.L. Blinov, A.S. Shemyakinsky. Teplov·yye i gazodinamicheskiye raschety gazoturbinnykh ustanovok: uchebno-metodicheskoye posobiye [Thermal and gas-dynamic calculations of gas turbine installations: an educational and methodical manual]. Yekaterinburg: Ural University Press, 2018, 164 p.

15. Zaichenko V.M., Kiverin A.D., Smygalina A.E., Tsyplakov A.I. Goreniye obednennykh smesey na osnove vodoroda v dvigatele s iskrovym zazhiganiyem [Combustion of hydrogen-based lean mixtures in a spark ignition engine]. Thermal Engineering, 2018, No. 4, pp. 87-99.

16. Fordoei E., Mazaheri K., Mohammadpour A. Effects of hydrogen addition to methane on the thermal and ignition delay characteristics of fuel-air, oxygen-enriched and oxy-fuel MILD combustion // International Journal of Hydrogen Energy, 2021, Volume 46, Issue, pp. 34002-34017.

17. Frolov S.M., Medvedev S.N., Basevich V.Ya., Frolov F.S. Samovosplameneniye i goreniye troynykh gomogennykh i geterogennykh smesey uglevodoroD–vodoroD–vozdukh [Spontaneous ignition and gorenje triple homogeneous and heterogeneous mixtures of hydrocarbon–hydrogen–air]. Russian Journal of Physical Chemistry B: Focus on Physics, 2013, vol.32, No. 8, pp.43-48.

The article analyzes the known solutions of vibration problems by technological methods and formulates their mathematical formulation. The direction of the research is determined and the hypothesis of solving the minimization problem is formulated.
A solution is proposed to minimize the vibration parameters of rotors with periodically freezing surfaces by giving them an elastic-stressed state, the results of its testing in industrial production conditions are presented.

Keywords: assembly, balancing, imbalance, eccentricity, rotor, vibration.

Sergey M. Beloborodov (Perm, Russian Federation) – Doctor of Technical Sciences, Professor of Department “Design of Artillery Weapons”, Perm Military Institute of the National Guard Troops of Russian Federation (1, Gremyachiy log str., Perm, 614030, e-mail: beloborodoff2011@yandex.ru).

Vladimir Ya. Modorskii (Perm, Russian Federation) – Doctor of Technical Sciences, Professor Department of Mechanics of Composite Materials and Constructions”, director of the High-Performance Computing Systems PNRPU center, Perm National Research Polytechnic University (29, Komsomolsky av., Perm, 614990, e-mail: modorsky@pstu.ru).

Aleksandr I. Neverov (Perm, Russian Federation) – Head of Department “The Artillery Armament Design” Perm Military Institute of the National Guard Troops of Russian Federation (1, Gremyachiy log str., Perm, 614030, e-mail: neverovai@rosgvard.ru).

1. Shmakov A.F. and Modorskii V.Ya. Energy Conservation in Cooling Systems at Metallurgical Plants // Metallurgist, 2016, no. 59, рр. 882-886.

2. Mekhonoshina, E.V., V. Ya Modorskii, and V. Yu Petrov. Numeric simulation of the interaction between subsonic flow and a deformable profile blade on the compressor experiment phase // Proceedings of International Conference Information Technology and Nanotechnology (ITNT-2015), 2015, pp. 211-218.

3. Mekhonoshina, E.V., and V.Ya Modorskii. Impact of magnetic suspension stiffness on aeroelastic compressor rotor vibrations of gas pumping units // AIP Conference Proceedings. AIP Publishing LLC, 2016, Vol. 1770, No. 1, P.030113, 6 p.

4. Butymova, L. N., V. Ya Modorskii, and V. Yu Petrov. Numerical modeling of interaction in the dynamic system “gas-structure” with harmonic motion of the piston in the variable section pipe // AIP Conference Proceedings. AIP Publishing LLC, 2016, Vol. 1770, No. 1, P.030103, 6 p.

5. Gaynutdinova, Dinara F., Vladimir Ya Modorsky, and Grigoriy F. Masich. Infrastructure of data distributed processing in high-speed process research based on hydroelasticity tasks // Procedia Computer Science, 2015, no. 66 (2015), pp. 556-563.

6. Nepomiluev V.V., Semenov A.N. Virtual Testing in Assembly // Russian Engineering Research, 2019, Vol. 39, No. 7, pp. 625-627.

7. A.E. Meshkas, V.F. Makarov, V.V. Shirinkin. Tekhnologii, pozvolyayushchiye povysit effektivnost obrabotki kompozitsionnykh materialov metodom frezerovaniya [Technologies that improve the efficiency of processing composite materials by milling]. Bulletin of the Tula State University. Technical sciences, 2016, no. 8-2, pp. 291-299.

8. Pesin M.V., Makarov V.F., Mokronosov YE.D. Osobennosti tekhnologicheskogo protsessa formoobrazovaniya rez'b na izdeliyakh mashinostroyeniya, obespechivayushchego povysheniye kachestva izdeliya i snizheniye yego sebestoimosti [Features of the technological process of forming threads on engineering products, providing an increase in the quality of the product and a reduction in its cost]. Exposition Oil & Gas, 2011, no. 6(18), pp 20-21

9. Beloborodov S.M., Makarov V.F., Tselmer M.L. Сontrolled assembly of rotors // Proceedings of the 5th International Conference on Industrial Engineering (ICIE 2019). Lecture Notes in Mechanical Engineering, 2020, Vol. 2, pp. 233-240.

10. Beloborodov S.M., Petrov V.Y., Modorskii V.Y., Tselmer M.L. Providing gas-dynamic tests for 2fsi subsystems // AIP Conference Proceedings, 2018, no. 2027, pp. 040089.

11. Makarov V.F., Nikitin S.P. Zavisimost predela vynoslivosti detaley iz zharoprochnykh splavov ot tekhnologicheskikh parametrov glubinnogo shlifovaniya [Dependence of the endurance limit of parts made of heat-resistant alloys on the technological parameters of deep grinding]. Collection of scientific papers of the XI-th International Scientific and Practical Conference: Modern tool systems, information technologies and innovations, 2014, pp. 16-20.

The proposed article is devoted to artificial material systems operating in conditions of information scarcity for effective management. The problem is considered on the example of rotors operating in conditions of icing of surfaces of turbine units used in aviation and the thermal power complex. The analysis of measures to ensure the dynamic stability of rotors, whose surfaces are subject to icing, leading to an uncontrolled increase in local imbalances, is carried out.

The relevance of the problem is due to both the general trend of scientific and technological progress aimed at improving technologies and types of products, and modern challenges of the economy. These should primarily include meeting the need for technological processes and types of products that are as close as possible to the requests in terms of the resource of work, cost, cost of operation and disposal. At the same time, the situation at the production site is complicated by the hostile attitude of the so-called Western countries to the development of Russian industry, especially in aviation, the thermal power complex, defense, electronics, etc.

All this creates a complex scientific and technical contradiction, burdened by a shortage of material support: financial insecurity and the absence of a number of components supplied by previously unfriendly countries. Based on the results of the analysis of the dynamic state of the systems, the direction of its technological support is determined. Two methods are proposed to ensure the dynamic stability of the most problematic elements of rotors: wheels of centrifugal and axial compressors (turbines).

At the same time, the method of precision preparation of rotor elements for assembly is designed to ensure the installation of the element on the shaft with minimized eccentricity of the forming seal and without imbalance, and the method of eccentricity-virtual assembly of turbine wheels is designed to balance the rotor with a pre–known imbalance. The application of the developed methods makes it possible to solve the formulated scientific and technical contradiction, significantly improve the quality of products, reduce the labor intensity and cost of production. Technological processes using these methods have been tested in industrial conditions.

Keywords: system, technology, assembly, surface, icing, dynamic stability, imbalance, eccentricity, rotor, vibration.

Sergey M. Beloborodov (Perm, Russian Federation) – Doctor of Technical Sciences, Professor, Department of “Design of Artillery Weapons”, Perm Military Institute of the National Guard Troops of Russian Federation
(1, Gremyachiy log str., Perm, 614030, e-mail: beloborodoff2011@yandex.ru).

Vladimir Ya. Modorskii (Perm, Russian Federation) – Doctor of Technical Sciences, Professor of Department “Mechanics of composite materials and constructions”, Director of the High-Performance Computing Systems PNRPU center, Perm National Research Polytechnic University (29, Komsomolsky av., Perm, 614990,
e-mail: modorsky@pstu.ru).

Dmitriy M. Tsimberov (Perm, Russian Federation) – CScinMartial Sciences, Head of the Department “Equipment Operation”, Perm Military Institute of the National Guard Troops of the Russian Federation (1, Gremyachiy log str., Perm, 614030, e-mail: cimberovdm@rosgvard.ru).

1. Shmakov A.F. and Modorskii V. Ya. Energy Conservation in Cooling Systems at Metallurgical Plants // Metallurgist, 2016, no. 59, рр. 882-886.

2. Mekhonoshina, E. V., V. Ya Modorskii, and V. Yu Petrov. Numeric simulation of the interaction between subsonic flow and a deformable profile blade on the compressor experiment phase // Proceedings of International Conference Information Technology and Nanotechnology (ITNT-2015), 2015, pp. 211-218.

3. Mekhonoshina, E.V., and V.Ya Modorskii. Impact of magnetic suspension stiffness on aeroelastic compressor rotor vibrations of gas pumping units // AIP Conference Proceedings. AIP Publishing LLC, 2016,
Vol. 1770, No. 1, P.030113, 6 p.

4. Butymova, L.N., V.Ya Modorskii, and V. Yu Petrov. Numerical modeling of interaction in the dynamic system “gas-structure” with harmonic motion of the piston in the variable section pipe // AIP Conference Proceedings. AIP Publishing LLC, 2016, Vol. 1770, No. 1, P.030103, 6 p.

5. Gaynutdinova, Dinara F., Vladimir Ya Modorsky, and Grigoriy F. Masich. Infrastructure of data distributed processing in high-speed process research based on hydroelasticity tasks // Procedia Computer Science, 2015, no. 66 (2015), pp. 556-563.

6. Nepomiluev V.V., Semenov A.N. Virtual Testing in Assembly // Russian Engineering Research, 2019, Vol. 39, No. 7, pp. 625-627.

7. Semenov A.N., Nepomiluyev V.V. Uchet vzaimodeystviya detaley v sborochnykh sistemakh kak sposob povysheniya kachestva i rabotosposobnosti [Taking into account the interaction of parts in assembly systems as a way to improve quality and efficiency]. STIN, 2019, No. 2, pp. 24-27.

8. A.E. Meshkas, V.F. Makarov, V.V. Shirinkin. Tekhnologii, pozvolyayushchiye povysit effektivnost obrabotki kompozitsionnykh materialov metodom frezerovaniya [Technologies that improve the efficiency of processing composite materials by milling]. Bulletin of the Tula State University. Technical sciences, 2016, no.8-2,
pp. 291-299.

9. Pesin M.V., Makarov V.F., Mokronosov YE.D. Osobennosti tekhnologicheskogo protsessa formoobrazovaniya rez'b na izdeliyakh mashinostroyeniya, obespechivayushchego povysheniye kachestva izdeliya i snizheniye yego sebestoimosti [Features of the technological process of forming threads on engineering products, providing an increase in the quality of the product and a reduction in its cost]. Exposition Oil & Gas, 2011, no. 6(18), pp. 20-21.

The paper considers the use of a granulated solid fuel engine as a propulsion system for an unmanned aerial vehicle, which will be able to solve different kinds of problems in extreme conditions (extreme temperatures and low oxygen content). Various schemes of propulsion system using granulated solid fuel have been developed and proposed: gas turbine and rocket-turbine engines (screw and jet type). The optimality criteria for the granular solid fuel are determined. The fuel components of the engine have been selected. The compositions of granular fuel based on ammonium perchlorate and polybutadiene with terminal hydroxyl substances have been studied. In accordance with the optimality criteria, a composition using HTPB 37 % was selected for calculations. The fuel parameters correspond to the optimality criteria (combustion temperature 1270 K, gas constant 457 kJ/(kgK), the density which is taking into account the porosity 930 kg/m3, k-phase 3 %. The calculation of the scheme of a gas turbine engine is made. The operating ranges of the parameters of the propulsion system are determined, such as: the ratio of air consumption to fuel (from 12.5 to 27.5), temperatures in the afterburning zone (1600–1100 K), specific power (3500–4300 kW / (kg / s)), efficiency (25–28 %), specific fuel consumption (0.83–1.06 kg/(kWh)). A gas turbine engine powered by granulated fuel is inferior to a modern piston engine in terms of specific fuel consumption (0.83 versus 0.58). However, a gas turbine engine on granulated fuel is significantly superior to a piston engine in terms of fuel consumption by 16% and efficiency by 1.8 times. An unmanned aerial vehicle powered by granulated solid fuel operates in extreme conditions with sufficiently high efficiency parameters.

Keywords: granulated solid fuel, thrust control, unmanned aerial vehicle, extreme conditions, reusable vehicle, supply system, gas turbine engine, rocket-turbine engine, efficiency parameters, power.

Andrey V. Elkin (Perm, Russian Federation) – PhD Student, Department “Rocket and Space Engineering and Power Generating Systems”, Perm National Research Polytechnic University (29, Komsomolsky av., 614990, Perm, e-mail: elkinav237@gmail.com).

Roman D. Gubin (Perm, Russian Federation) – PhD Student, Department “Rocket and Space Engineering and Power Generating Systems”, Perm National Research Polytechnic University (29, Komsomolsky av., 614990, Perm, e-mail: qwerty.gubin@gmail.com).

Vladimir I. Malinin (Perm, Russian Federation) – Doctor of Technical Sciences, Professor, Department “Rocket and Space Engineering and Power Generating Systems”, Perm National Research Polytechnic University (29, Komsomolskiy av., 614990, Perm, e-mail: malininvi @ mail.ru).

1. D.S. Legkonogih, A.A. Krylov, M.S. Ivanov. Sovremennoe sostoyanie i perspektivy razvitiya silovyh ustanovok bespilotnyh letatelnyh apparatov [The current state and prospects for the development of power plants for unmanned aerial vehicles]. STRATEGIC OFFENSIVE FORCES, 2019, no. 4, pp. 57-72.

2. A.N. Kostyuchenkov, V.P. Minin, S.A. Klement'ev, A. V. Fedin. Nauchno-tekhnicheskie problemy sozdaniya i proizvodstva rotorno-porshnevyh dvigatelej dlya BPLA za rubezhom [Scientific and technical problems of development and production of rotary piston engines for UAVs abroad]. Innovatics and Expert Examination, 2019, no. 3(28), pp. 143-156. – DOI 10.35264/1996-2274-2019-3-143-156.

3. Evtushenko E.V., Volodin A.V. Analiz sushchestvuyushchih tipov bespilotnyh letatel'nyh apparatov i perspektiv ih razvitiya [Analysis of existing types of unmanned aerial vehicles and prospects for their development]. Proceedings of the All-Russian (with international participation) scientific and practical conference “Intellektualnye sistemy, upravlenie i mekhatronika”, 18–20 September 2017, Sevastopol, pp. 299–305.

4. Klippstein H, Hassanin H, De Cerio Diaz, Sanchez A, Zweiri Y, Seneviratne L. Additive manufacturing of porous structures for unmanned aerial vehicles applications. Advanced Engineering Materials, 2018, Vol. 20 (9), P. 1800290.

5. Fire extinguishing system for high-rise buildings and rugged mountainous terrains utilizing quadrotor unmanned aerial vehicle. / Abdel Ilah N. Alshbatat // International Journal of Image, Graphics and Signal Processing, 2018, Vol. 1, pp. 23-29.

6. A. A. Azyazov, D. D. Tolubeev, D. N. Dyunova. Ispolzovanie bespilotnyh letatelnyh apparatov dlya preduprezhdeniya i likvidacii chrezvychajnyh situacij [he use of unmanned aerial vehicles for the prevention and elimination of emergency situations]. Collection of materials of the All-Russian Scientific and Practical Conference “Aktualnye problemy obespecheniya pozharnoj bezopasnosti i zashchity ot chrezvychajnyh situacij”, Zheleznogorsk, April 23, 2021, pp. 524-527.

7. Vinokurova V.V., Bobryshev A.A. Neobhodimost primeneniya i razvitiya bespilotnyh letatelnyh apparatov v MCHS Rossii [The need for the use and development of unmanned aerial vehicles in the Russian Emergencies Ministry]. Pozharnaya bezopasnost': problemy i perspektivy, 2016, no. 1(7), pp. 14-16.

8. Tatarinov V.V., Kalajdov A.N., Mujkich E. Primenenie bespilotnyh letatelnyh apparatov dlya polucheniya informacii o prirodnyh pozharah [The use of unmanned aerial vehicles to obtain information about wildfires]. Technology of technosphere safety, 2017, no. 1(71), pp. 160-168.

9. Legkonogih, D. S. Eksperimentalnye issledovaniya harakteristik elektricheskih silovyh ustanovok dlya legkih BLA [Experimental studies of the characteristics of electric power plants for light UAVs]. Vestnik USATU, 2022, vol. 26, no. 1(95), pp. 81-91. – DOI 10.54708/19926502_2022_2619581.

10. The design of a rotary-wing unmanned aerial vehicles–payload drop mechanism for fire-fighting services using fire-extinguishing balls / Ali Magdi Sayed Soliman, ·Suleyman Cinar Cagan, Berat Baris Buldum // Applied Sciences, 2019, Vol. 1, P. 1259.

11. D.V. Usov, M.A. Muraeva, N.S. Senyushkin, R.R. YAmaliev. Osobennosti klassifikacii BPLA samoletnogo tipa [Features of the classification of aircraft-type UAVs]. Molodoy uchenyy, 2010, no. 11(22), pp. 65-68.

12. D.A. Zvyagincev, M.M. Fedotov, Yu. V. Zinenkov. Sposob povysheniya effektivnosti silovoj ustanovki bespilotnogo letatelnogo apparata [Method for increasing the efficiency of the power plant of an unmanned aerial vehicle]. Vestnik USATU, 2022, vol. 26, no. 1(95), pp. 48-58. DOI 10.54708/19926502_2022_2619548.

13. Elkin, A. V. Raketnye dvigateli dlya kosmicheskih letatel'nyh apparatov na psevdoozhizhennyh tverdyh toplivah [Rocket engines for spacecraft on fluidized solid propellants]. Thermal Processes in Engineering, 2021, vol. 13, no. 11, pp. 509-518. – DOI 10.34759/tpt-2021-13-11-509-518.

14. A. V. Elkin, E. S. Zemerev, V. I. Malinin [i dr.]. Raketnyj dvigatel na granulirovannom tverdom toplive [Rocket engine on granular solid fuel]. PNRPU Aerospace Engineering Bulletin, 2021, no. 64, pp. 16-24. – DOI 10.15593/2224-9982/2021.64.02.

15. Effect of Coating of Ammonium Perchlorate with Fluorocarbon on Ballistic and Sensitivity Properties of AP/Al/HTPB Propellant / S. Nandagopal, M. Mehilal, M. A. Tapaswi, S. N. Jawalkar, K. K. Radhakrishnan, B. Bhattacharya // High Energy Materials Research Laboratory, 2008, Vol. 34, pp. 526-531.

16. Trusov B.G. Modelirovanie himicheskih i fazovyh ravnovesij pri vysokih temperaturah: Instrukciya polzovatelya Astra 4 [Modeling of chemical and phase equilibria at high temperatures: Astra 4 user manual]. Moscow: MSTU named after N.E. Bauman, 1991, 36 p.

Volcanic ash clouds emitted into the Earth’s atmosphere by more than a thousand active volcanoes pose an immediate serious threat to flight safety, since volcanic ash particles in high concentrations can cause significant damage to aircraft.

This article presents the consequences of an aircraft getting into a cloud of volcanic ash (damage to the fuselage and aerodynamic surfaces of the aircraft, turbojet sustainer engines, antennas, air pressure and temperature receivers, other aircraft systems), and also describes in detail the mechanisms and examples of the impact of volcanic ash on various types aircraft gas turbine engines. The global statistics of aircraft hitting volcanic ash clouds from 1935 to 2021 is given.

The results of engineering tests of PW F100 bypass gas turbine engines under the influence of volcanic ash in the conditions of the scientific and CalspanTechnical Corporation, founded in 1943 in the United States of America, are considered. Also presented are the results of work under the VIPR (Vehicle Integrated Propulsion Research) program of the National Aerospace Agency of the United States of America (NASA) for a comprehensive study of the impact of volcanic ash on the F-117 (PW2040) power plant of the Boeing C-17 Globemaster III military transport aircraft. The results of research by the NASA national agency and the Calspan Corporation are compared with the main data of certification tests of the advanced PD-14 aircraft gas turbine engine developed by JSC «UEC-Aviadvigatel» in the conditions of the closed ground test facility Ts-17T of the FAA «CIAM named after P.I. Baranov» in accordance with the requirements of the European Aviation Safety Agency (EASA).

Keywords: volcanic ash, aircraft gas turbine engine, combustion chamber, turbine, turbine nozzle blades, erosion, cooling holes clogging, glass transition, surge, andesite.

Diana D. Popova (Perm, Russian Federation) – Postgraduate Student, Perm National Research Polytechnic University (13, Professor Pozdeevь str., 614013, Perm), Engineer of the Turbine Department, UEC-Aviadvigatel (93, Komsomolskiy av., 614990, Perm, e-mail: popova-dd@avid.ru).

Aleksei N. Sazhenkov (Perm, Russian Federation) – PhD in Technical Sciences, Assistant to Managing Director-General Designer, UEC-Aviadvigatel (93, Komsomolskiy av., 614990, Perm, e-mail: office@avid.ru).

1. Manual on Volcanic Ash, Radioactive Material and Toxic Chemical Clouds // International Civil Aviation Organization, Third edition, 2015, 210 p.

2. Chekhov I.A. Osobennosti vypolneniya poletov v rayonakh s vulkanicheskoy deyatelnostyu [Features of flights in areas with volcanic activity]. International scientific and practical conference “Nauka iobrazovanie: problemy, idei, innovacii”, 2019, pp. 80-84.

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5. Christopher A. Wood, Sonya L Slater, Matthew Zonneveldt, John Thornton, Nicholas Armstrong and Ross A. Antoniou. Characterisation of Dirt, Dust and Volcanic Ash: A Study on the Potential for Gas Turbine Engine Degradation. Defense Science and Technology Group, Australia, May 2017, 66p.

6. Fearnley, Carina & Bird, Deanne & Haynes, Katharine &Mcguire, Bill & Jolly, Gill. (2018). Observing the Volcano World: Volcano Crisis Communication: Volcano Crisis Communication. Springer; Softcover reprint of the original 1st ed. 2018, 786 p.

7. Christmann C., Nunes R., Schmitt Ang., Guffanti M. Flying into Volcanic Ash Clouds: An Evaluation of Hazard Potential. PUBLIC RELEASE, 2017, 18 p. DOI: 10.14339/STO-MP-AVT-272.

8. Guffanti M., Casadevall, T.J., Budding K. Encounters of aircraft with volcanic ash clouds: a compilation of known incidents, 1953-2009: U.S. Geological Survey, Reston, Virginia: 2010, 16 p.

9. John D. L., Mark R. W., Clinton W. St. J., Michael W. V., Larry M. Vehicle Integrated Propulsion Research (VIPR) III Volcanic Ash Ingestion Testing. National Aeronautics and Space Administration, May 15-17, 2017, 64 p.

10. Girina, O. A., Gordeyev, Ye. I. Proyekt KVERT – snizheniye vulkanicheskoy opasnosti dlya aviatsii pri eksplozivnykh izverzheniyakh vulkanov Kamchatki i Severnykh Kuril [The KVERT project – reducing the volcanic hazard for aviation during explosive eruptions of the volcanoes of Kamchatka and the Northern Kuriles]. Vestnik of Far Eastern Branch of Russian Academy of Sciences, 2007, no. 2, pp. 100-109. URL: http://elibrary.ru/item.asp?id=10082046 (Accessed: 01.10.2022).

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12. Dunn, M. Operation of Gas Turbine Engines in an Environment Contaminated With Volcanic Ash. Journal of Turbomachinery, 2012, Vol. 134, Art. No. 051001. DOI: 10.1115/1.4006236

13. Davison C. R., Rutke T. Assessment and Characterisation of Volcanic Ash Threat to Gas Turbine Engine Performance // National Research Council Canada, Ottawa, Canada, August, 2014, Vol. 136, 10 p

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15. InozemcevA.A., PopovaD.D. Issledovaniye ustoychivosti aviatsionnogo dvigatelya PD-14 k vozdeystviyu vulkanicheskogo pepla [Study of the stability of the aircraft engine PD-14 to the effects of volcanic ash]. VESTNIK USATU, vol. 26, no. 2(96), 2022, pp. 60-70.

16. Pavletsov I.S. and others. Gazogenerator dvigatelya PD-14 uspeshno proshel ispytaniya vulkanicheskim peplum [The gas generator of the PD-14 engine has successfully passed tests with volcanic ash]. Informatsionno-tekhnicheskiy byulleten "Permskiye aviatsionn·yye dvigateli", 2021, no. 48, pp. 30-33.

One of the ways to increase the vibration strength gas turbine engine parts is the use of dry friction dampers. The efficiency of such dampers essentially depends on the selection of their mass-rigidity characteristics, pressing force, and other parameters. For the correct choice of these parameters at the design stage, it is necessary both to understand the laws of operation of dampers and to have an adequate mathematical model of the process of interaction between the engine part and the damper.

The proposed mathematical model for calculating the efficiency of dry friction dampers is based on the linearization of the described Coulomb friction processes, which is completely true for cases where only the macroslip process is presented. However, real processes of dry friction are also accompanied by microslip processes too.

To evaluate the influence of the presence of microslip processes on the damping efficiency, and, as a result, on the accuracy of the created mathematical model, an experimental assessment of the indirect hysteresis loss loops of the “damper-detail” system was carried out on a model installation.

It is concluded that the damper displacement level and the surface roughness are proportional. A possibility to apply linearised model to full-scale components was justified by calculations. This includes the possibility to consider the microslip effects simulations and identify ways of the damper adjustment so as to minimise the influence of this effect. The results of the study are taken into account for the damped gearwheel model adjustment.

Keywords: logarithmic decrement of vibrations, Coulomb friction, longitudinal mode oscillator, hysteresis loss loops, bevel gear wheel, gas turbine engine, damper, resonance, microslip effects.

Vadim N. Yakovkin (Perm, Russian Federation) – Head of Team, UEC-Aviadvigatel (93, Komsomolsky av., Perm, 614990, e-mail: jakovkin88@mail.ru).

Mikhail Sh. Nikhamkin (Perm, Russian Federation) – Doctor of Technical Sciences, Professor, Department of Aviation Engines, Perm National Research Polytechnic University (29, Komsomolsky av., Perm, 614990,
e-mail: Nikhamkin@mail.ru).

Nikolay A. Sazhenkov (Perm, Russian Federation) – CSc in Technical Sciences, Department of Aviation Engines, Perm National Research Polytechnic University (29, Komsomolsky av., Perm, 614990, e-mail: sazhenkov_na@mail.ru).

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7. E.V. Kozharinov, Yu.M. Temis. Analiz vliyaniya dempfera sukhogo treniya na dinamiku konicheskogo zubchatogo kolesa [Analysis of the influence of a dry friction damper on the dynamics of a bevel gear]. BMSTU Journal of Mechanical Engineering, 2015, no. 7(664), pp. 20-28.

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9. V.N. Yakovkin, V.A. Besschetnov. Matematicheskaya model ostsillyatora s sukhim treniyem pri vynuzhdennykh kolebaniyakh [Mathematical model of an oscillator with dry friction under forced vibrations]. Proceedings of the XIX All-Russian Scientific and Technical Conference «Aerokosmicheskaya tekhnika, vysokiye tekhnologii i innovatsii – 2018», 2018, vol. 1, pp. 355-358.

10. Yakovkin, V. N. Verification of a Mathematical Model of a Dry Friction Damper for a GTE Blade / V.N. Yakovkin, V.A. Besschetnov // Journal of Physics: Conference Series: materials of International Conference on Aviation Motors (ICAM 2020). Moscow, 18-21 May 2021, Vol.1891, P. 012037.

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There are some methods to improve vibration strength of the gas turbine engine bevel gearwheels by using the dry friction dampers capable of damping resonance vibrations and operate under extreme conditions. The effectiveness of these dampers depends significantly on an adjustment of their mass-stiffness properties, pressure and other parameters. It is required to understand the damper operation laws to make a right choice of the parameters during designing, and that could be addressed by test simulations.

This paper provides an acceptability assessment of a mathematical model based on the Coulomb friction linearisation in a damper-to-gearwheel contact within the gas turbine engine. Bevel gearwheels have a complex dimensional mode configuration in the damper contact area, therefore a calculation analysis of dynamic behavior of the linearised gearwheel-damper system was carried out from the nominal contact parameters, such as contact fit, stiffness of the normal elastic members in the contact. It is concluded that the damper slipping and the surface roughness are proportional. The stable solution limits have been defined to minimise the unknown parameters effect on the calculation result when adjusting the damper. The research results are used when adjusting the damper for the aircraft engine gearwheel. The strain-gauging test data were compared to the calculation results for the engine damped gearwheel, an acceptable convergence on damping has been obtained.

Keywords: logarithmic decrement of vibrations, Coulomb friction, bevel gearwheel, gas turbine engine, dry friction damper, resonance, microslip effects, scaling factor.

Vadim N. Yakovkin (Perm, Russian Federation) – Head of Team, UEC-Aviadvigatel (93, Komsomolsky av., Perm, 614990, e-mail: jakovkin88@mail.ru).

Aleksandr B. Pishchalnikov (Perm, Russian Federation) – Leading Engineer, UEC-Aviadvigatel
(93, Komsomolsky av., 614990, Perm, e-mail: pishalnikov2012@mail.ru).

Ilya I. Sokolov (Perm, Russian Federation) – Head of Team, UEC-Aviadvigatel (93, Komsomolsky av., 614990, Perm, e-mail: Sokolov-ii@avid.ru).

Mikhail Sh. Nikhamkin (Perm, Russian Federation) – Doctor of Technical Sciences, Professor, Department of Aviation Engines, Perm National Research Polytechnic University (29, Komsomolsky av., 614990, Perm,
e-mail: Nikhamkin@mail.ru).

Nikolay A. Sazhenkov (Perm, Russian Federation) – CSc in Technical Sciences, Department of Aviation Engines, Perm National Research Polytechnic University (29, Komsomolsky av., 614990, Perm, e-mail: sazhenkov_na@mail.ru).

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