CONTENTS #1 – 2 (January – February) 2023
Nonlinear Deformation and Stability of Anisogrid Circular Cylindrical Shells Under Pure Bending (p. 3 – 15)
The stability under pure bending of an anisogrid circular cylindrical shell made of a composite material was investigated. The research results were obtained on the basis of a technique developed by the author that implements the finite element method for solving the problems of strength and stability of discrete-reinforced cylindrical shells made of the composite material, taking into account the moment- ness and nonlinearity of their subcritical stress-strain state. The effect of deformation nonlinearity, reinforcing set stiffness, reinforcement layup angles, and shell thickness on the critical loads of the shell instability was determined.
Keywords: cylindrical composite shells; discrete reinforcement; nonlinear deformation; stability; finite element method.
Near-Earth Space Testing: New Data (p. 16 – 24)
The article presents new information about the inorganic near-object environment of the ISS, obtained in the space experiment "Test" along with exobiological research in the search for viable microorganisms in space.
Keywords: origin of life; panspermia; fine sediment; inorganic elements; active medium in the ionosphere; contamination and cosmochemical stability of space equipment.
he Main Dependencies in the Power Supply Units of Hydraulic Systems (p. 25 – 32)
A.A. Volkov, V.G. Dolgushev, Yu.N. Pugachev, K.E. Sorokin
The paper considers the issues of choosing a mathematical model of a hydraulic system. The design and structural schemes for determining the parameters of the power supply are considered in the most typical form for an airplane task. All the main stages of the development of the general model of the hydrocomplex are described.
Keywords: имитационная модель гидросистемы; энергетические характеристики гидросистемы; модели функциональных подсистем; гидрокомплекс.
A Method for Calculating the Aerodynamic Characteristics of the Rotor Blade Profile of a Helicopter with a Controlled Flap (p. 33 – 42)
V.A. Ivchin, M.V. Kargaev
Semi-empirical formulas were obtained for calculating the aerodynamic characteristics of the main rotor blade profile of a helicopter with a controlled flap, including hinge moments, depending on the deflection angles, flap width, angles of attack and Mach numbers. These dependences were obtained on the basis of experimental data of purges of various profiles with a slit flap and a flap in the form of a plate in the area of direct flow.
Keywords: main rotor blade; profile; controllable flap; aerodynamic characteristics; helicopter.
Computational Investigation of Influence Wing Twist on Aerodynamic Characteristics of the Aircraft Model (p. 43 – 50)
V.V. Vozhdaev, А.I. Volkov, А.А. Krutov, Е.А. Pigusov
On the basis of numerical solutions of the Reynolds averaged Navier – Stokes equations the aerodynamic characteristics of a heavy transport aircraft aerodynamic model with cruise wing twist and aerodynamic models twist were calculated. It is shown that the numerically obtained data with cruise wing twist better matches with experimental data.
Keywords: computational fluid dynamics; Navier – Stokes equations; computational grid; aerodynamic characteristics; cruise wing twist; aerodynamic models twist.
Assessment of the Erosion Wear Influence on the Operational Parameters of the Gas Turbine Unit’s Axial Compressor With CFD (p. 51 – 60)
V.L. Blinov, I.S. Zubkov
The paper presents the method for the creation eroded compressor blades and results of the numerical simulation of the transonic axial compressor stage NASA Stage 37 with critical erosion wear. Based on the computational results the method for prediction the influence of the erosion’s intermediate degrees was demonstrated and analyzed. The perspective methods for further stages of the study were noted.
Keywords: gas turbine unit; axial compressor; blade row; defects; dust erosion; computational fluid dynamics.
Methodology for Taking into Account the Requirements for Reliability when Choosing Design Solutions for the Load-Bearing Structures of Launch Vehicles (p. 61 – 69)
A.A. Zolotov, V.V. Rodchenko, E.V. Gusev
The article discusses the features of harmonization of design solutions for fuel tanks and dry compartments with measures to ensure their reliability. Based on the analysis, a methodology is proposed that allows justifying rational levels of boost pressure and characteristics of the structural power scheme, providing maximum levels of reliability of the design of fuel tanks and dry compartments. The performance of the presented approaches is illustrated by specific examples. The results obtained can be useful to engineering and technical workers of enterprises, as well as students of the relevant profile.
Keywords: fuel tank; dry compartment; boost pressure; probability of failure-free operation.
Regeneration of Eye Tentacles and the Head of Helix Lucorum During a Multi-Day Orbital Flight on the International Space Station (p. 70 – 80)
The results of two 163-day space experiments on the terrestrial pulmonary snail Helix lucorum are summarized. The snails were divided into three experimental groups: a flight group (107 snails) and two control groups – a synchronous escort group (81 snails) and a vivarium group (114 snails). Eye tentacles were amputated on one or both sides of 98 snails of the flight group 10...12 hours before the start of the experiments. A similar procedure was performed on the snails of the control groups. Nine snails of the flight group had their heads cut off along with their labial and ocular tentacles. The visual state of native and regenerated eyes was assessed by an electroretinogram (ERG) for single and paired light stimuli of different brightness and duration. The research started from the first day and continued with a certain periodicity for 4 years after the completion of space experiments. Regenerates of both flight and control snails were shorter and thinner compared to native eye tentacles. The eye glasses and their lenses were noticeably smaller, the optic nerve was thinner. The visual function was preserved in working condition, but with certain flaws: ERG in regenerated eyes had a large latency and a small peak amplitude compared to the response of native eyes to light stimuli. The "Saturation plateau" was shifted towards lower values of light exposure. In flight snails, the severed head regenerated with all the tentacles, mouth, jaw and pharynx, and they demonstrated normal eating behavior.
Keywords: Construction and Researches of Radiating Model of Infrared Sourse IET-29 with Reference to Conditions Thermal Vacuum Tests of Products of Space Technic
Construction and Researches of Radiating Model of Infrared Sourse IET-29 with Reference to Conditions Thermal Vacuum Tests of Products of Space Technics (p. 81 – 94)
V.A. Ulyanov, N.P. Sizyakov, A.D. Polyakhov, I.A. Yurev
In maintenance of imitation of external thermal loading at conducting thermal vacuum tests of products of space-rocket technics in thermal vacuum chambers VK 600/300 FKP "NIC RKP”. With use of the simulator of infrared radiation the radiating model of radiation source IET-29 is developed. Results of settlement researches of a directional distribution of the radiant fluxes created by emitter IET-29 at various rules of the radiating element in the rejector and for various values of electric power brought to it are resulted. The gained design data allow to solve methodical questions of imitation of external thermal loading as at a program and technique development cycle thermal vacuum tests of products of space technics, and at the analysis of their results. Initial data for construction of analytical model of a directional distribution of the radiant fluxes created by radiation source IET-29 are gained. Additional possibilities on management methods by a directional distribution of radiant fluxes from emitters IET-29 are presented.
Keywords: infrared radiation simulator; emitter; radiating element; radiating characteristics; radiating model; a directional distribution of radiant fluxes; thermal vacuum tests; program and technique of tests; thermal regime; thermal vacuum chamber; geometrical model; electric power; blackness extent.
Analysis of Software Package for Thermodynamic Calculations of Liquid Rocket Engines (p. 95 – 104)
А.Д. Максимов, Т.А. Максимова
Thermodynamic calculation is the basis for the design of rocket engines, since it solves a wide range of tasks related to ensuring optimal engine output parameters. The article presents a comparative analysis of the TERRA, ASTRA and ANSYS CFX software packages in relation to the thermodynamic calculation of rocket engines. The object of the study is the RE0146D on an oxygen-hydrogen propellant system. The comparison of complexes by component composition and by specific parameters of the chamber is shown. Verification of TERRA and ASTRA with reference values from the fundamental manual of V.P. Glushko was carried out.
Keywords: liquid rocket engine; thermodynamic calculation; software package.