Amelyushkin I. A. , Druzhinin O. V.
The study presents new structural designs of adaptive wings and evaluates their aerodynamic benefits. A comparative analysis and a concise review of existing adaptive wing concepts were carried out. The investi-gation included determining the variation of the center of pressure along the wing chord with changes in the angle of attack. The results were compared with those for a conventional high-lift wing and a clean wing pro-file. The obtained data can be applied to the design of short takeoff and landing (STOL) aircraft to enhance overall aerodynamic efficiency and control performance.
Makarenko N. I., Maltseva J. L.
Two classes of nonlinear problems concerning wave and jet structures in steady flows of an inhomogene-ous fluid are considered. One of them is related to the modeling of lee waves in atmospheric airflows over uneven terrain. The other group of problems concerns the description of internal waves in deep-ocean cur-rents. A common feature of both cases is the combined use of analytical approaches and computer algebra methods to construct asymptotic solutions of the equations of motion of a stratified fluid. The first approx-imate model is employed for the numerical calculation of jet-flow patterns and the nonlinear interference of lee waves over complex topography. The second model is used to characterize the qualitative properties and parameters of solitary internal waves in layered weakly stratified near-bottom flows.
Brutyan M. A., Pavlenko O. V., Ye Htun
Interest in various active and passive methods of flow control over an airfoil, aimed at increasing the max-imum lift coefficient of a wing, is driven by the relevance of reducing take-off and landing distan-
ces. Unlike active flow control methods, which require energy input, passive methods use the energy of the external airflow in such a way as to produce an overall beneficial effect. Passive flow control methods are simpler than active ones, have more reliable designs, and generally add little extra weight.
This work presents a passive method for controlling the flow over a high-lift wing airfoil with a flap by means of specially profiled flow channels. The described control method is effective both with the flap undeflected (cruise flight mode) and with the flap deflected. It is shown that in the profiled channel the airflow acceler-ates and exits tangentially onto the upper surface of the flap, increasing suction and shifting the boundary-layer separation line on the deflected flap downstream. Humid air with increased moisture concentration raises the momentum coefficient of the blown jet.
Babuk V. A., Burachek E. S.
The article examines approaches to modeling the combustion process of high-energy pasty propellants. A physical picture of the combustion process is presented. A mathematical framework is developed that ac-counts for the influence of the thickness and porosity of an intermediate structure in the combustion zone – the skeleton layer (SL). A multi-parameter optimization problem is formulated as a tool for the study. A se-quence for applying the optimization procedure to propellant formulations is defined, taking into account the specific features of their combustion processes. Simulation results are obtained that confirm the validity of the adopted assumptions. Directions for further research are identified.
Andryushkin A. Yu., Kazakova A. O., Romanat N. I.
Thermoplastics are widely used in the manufacturing of structural components for unmanned aerial vehicles (UAVs). Under sustained and variable loading, polymers exhibit creep, which significantly affects crack de-velopment. Therefore, determining critical crack opening and stresses acting at the crack tip, with considera-tion of material creep, is of practical importance.
The study presents formulas for evaluating the mechanical properties of a polymer over time under creep conditions. A methodology for calculating crack opening in a polymer plate subjected to stresses acting in the near-tip region has been developed using the boundary element method. It has been established that critical crack opening is characterized by the condition Dymax ≥ DC, where Dymax and DC denote the maximum and critical crack opening, respectively. The practical significance of the proposed methodology is demonstrated through the calculation of crack opening and crack-tip stresses in a polypropylene plate under creep conditions.
Pravidlo M. N., Biryukov P. A., Yurlovsky A. F.
Methods for constructing complex flight trajectories of aircraft are analyzed, and the specific features of their formation are examined. A universal algorithm is proposed for generating an arbitrary spatial trajectory for a maneuvering aircraft in simulation tasks. The algorithm involves forming a sequence of motion segments that implement elementary maneuvers. Possible variants of the algorithm’s construction, as well as limitations and extensions in its implementation, are discussed.
Syrovoy G. V., Pobeda T. V., Atroshenko D. V.
The article examines current approaches to enhancing the autonomy of unmanned aerial vehicles (UAVs) under emergency conditions. The importance of UAV autonomy for the effective execution of search-and-rescue, monitoring, and emergency recovery operations in disaster zones is substantiated, where traditional methods are often impractical due to high risk to personnel and limited access to incident sites.
An analysis of modern technological solutions is conducted, including computer vision systems with AI al-gorithms, multi-sensor navigation complexes, onboard computing platforms, and algorithms for route and energy optimization. Based on studies from 2022–2025, the effectiveness of LiDAR systems, modular navi-gation interfaces, and edge-computing technologies is evaluated. Key limitations are identified, such as de-pendence on satellite navigation, vulnerability of communication channels, limited energy resources, and restricted computational capacity of onboard systems.
The following development directions are proposed: integration of quantum sensors, adoption of hybrid power systems, and use of adaptive algorithms for collective swarm behavior of UAVs. Recommendations are formulated for standardizing autonomy requirements for UAVs in emergency situations and for estab-lishing testing grounds to validate operational scenarios. It is shown that a comprehensive approach to en-hancing autonomy can yield a manifold increase in the responsiveness and safety of emergency rescue op-erations.
Nilov A. S., Butorina I. A., Mokhova E. A.
This paper presents methods for calculating the parameters of the porous medium in unidirectional compo-site materials (CMs) with various types of regular (hexagonal and tetragonal) and irregular fibrous structures. The porous medium is represented as a system of inter-bundle and intra-bundle pores. These calculation methods can be considered as elements for describing the initial and current structure of CMs when model-ing chemical vapor infiltration (CVI) processes of fibrous preforms during the fabrication of composite ma-terials with carbon and ceramic matrices.
Brovka G. P., Lysenko S. A., Agutin K. A., Murashko A. A., Brovka A. G.
The article substantiates two non-destructive testing methods — non-contact and contact — designed to determine the thermophysical properties of materials by locally heating a semi-infinite medium using a disk-shaped heat source. During processing of the heating thermogram obtained with a non-contact source, the homochronicity parameter is used, defined as the ratio of the average rates of surface temperature change taken from different sections of the heating thermogram. It is established that, for certain geometric dimen-sions of the heat source and temperature measurement points, the homochronicity parameter ε is functional-ly related to the product of the material’s thermal diffusivity and the temperature measurement time. This makes it possible, using nomograms derived from preliminary numerical calculations for a series of materi-als with known thermophysical properties, to determine the thermal diffusivity and thermal conductivity coef-ficients of the test materials without employing complex methods for solving inverse heat conduction prob-lems.
The contact method involves time-resolved detection of the excess temperature at the center or at a certain distance from the disk-shaped heat source, and interpretation of the temperature profile using nomograms obtained with consideration of the heater’s heat capacity and the homochronicity parameter values, or by means of a neural network that establishes a relationship between the heating thermogram parameters and the target thermophysical properties.
Sotnikova N. V., Konoplev Yu. V., Motovilov A. O.
This work addresses the problem of creating a compact, high-speed, low-noise microwave frequency syn-thesizer. A solution is proposed in the form of a detailed description of a promising synthesizer architecture. Brief information is provided on the main frequency synthesis methods, and the advantages and disad-vantages of each method are analyzed. A definition of the hybrid frequency synthesis method is formulat-ed. Computer simulation results are presented that confirm the advantages of a hybrid architecture combin-ing phase-locked loop (PLL) and direct digital synthesis (DDS) techniques, enabling signal generation over a wide frequency range while achieving low phase noise and preserving high speed and other benefits.