A new technology is suggested for cleaning duplex nozzles of the aircraft engine fuel manifold from products of carbonization and carbon deposits. This technology can be implemented without removing the engine from the aircraft and its disassembly. The experimental development of the technology is performed for different operation modes, the most effective conditions of cleaning are defined, endoscopic

The rendezvous of two spacecraft (passive and active) using a tether system is studied. Two laws of the tether control are proposed to ensure the safe rendezvous of bodies. A minimum allowable thrust of the active spacecraft and the parameters of the tether control laws are defined, under which the rendezvous is implemented safe. Based on the results of numerical simulation, the ability to control

The influence of a bilateral flare of the flow path of the turbine nozzle vane on the flow pattern and energy losses was investigated, a search was made for ways to improve the aerodynamic performance of a such kind of units. According to viscous flow calculations, the bilateral flared flow path affects the airfoil loading along the whole height of the vane, increasing velocities on both sides of the

The mechanism of flame stabilization in phase-inhomogeneous air—fuel mixtures is considered. A method is proposed for refining the thermal theory of flame stabilization by taking into account the heat consumed for heating and evaporation liquid fuel in the ignition zone. An analytical dependence is obtained for the calculation of flaming out curves during the steady combustion of two-phase mixtures

The technology is revealed for measuring air parameters aboard the single-rotor helicopter using the information of the aerodynamic field of a main rotor vortex column perceived by a fixed multifunctional receiver made as a two-channel scheme with an ion-mark and aerometric channels. The algorithms of forming and processing the information, technical characteristics of the system obtained by the results

Based on a new fracture mechanics parameter, this study is concerned with assessment of the lifetime of a cracked aircraft gas turbine engine compressor disk operating under low cyclic loading conditions. In combination with the elastic-plastic properties of the VT3-1 titanium alloy, various combinations of angular velocity, temperature, surface flaw form and size are considered. A lifetime prediction

The paper studies the effect of drag reduction in a two-medium boundary layer due to sliding at the interface region. The results obtained by authors in the framework of the boundary layer theory are in good agreement with those obtained by integrating the continuum equations of motion for film flows in the ANSYS Fluent package with reduction of computational time for the first case.

The problem of synthesizing the pitch angle control system with the angle of attack limiting channel is considered. The problem of matching the trajectories of the system of the pitch angle control mode and the angle of attack limitation mode is discussed. An approach is proposed based on using a generalized characteristic of the system, which ensures the matching the states at an arbitrary moment

On the basis of bench tests, the relationship between the vibration signal and the state of the gear coupling of the Mi-26 helicopter is shown. By the methods of spectral transformations and Hilbert–Huang transform, informative signs are established that characterize the wear of teeth and splines. The results obtained can be used in the on-board diagnostics system of the helicopter to determine the

A portable normal incidence interferometer is developed, which allows determining the acoustic characteristics of the full-scale liners of an aircraft engine. Studies of large sound-absorbing panels used for lining the aircraft engine ducts are carried out. It is demonstrated that the panels have uniform acoustic characteristics in azimuthal direction.

The paper deals with the problem of constructing the distribution law of the normal component of injection velocity in a turbulent boundary layer at supersonic flow velocities. The problem is solved using the Dorodnitsyn generalized method of integral relations and the Lagrange formalism. The computational experiments conducted have shown the efficiency of optimal controls in comparison with the uniform

The paper discusses the possibilities of using the navigation user equipment on the basis of determining the angular position of space rockets in flight taking into account the special features of the control process. The task statement is given on clarifying the angular position on the active trajectory leg and identifying the abnormal operation of the meters of inertial navigation systems on the

The paper describes the computational and experimental investigation in selecting the design parameters of control surfaces and characteristics of the lift engines of a VTOL unmanned aerial vehicle. The general structural scheme of equations to roll, pitch and yaw control and stabilization is analyzed. Results of numerical simulation of the point-to-point autonomous flight are given.

As a result of 3D calculation in the ANSYS CFX software, combinations of ribs and oval trenches are revealed of the maximal thermal performance, intensification of heat exchange, and minimal drag coefficients.

An integrated method for optimization of a welded portion of a high pressure compressor rotor as a single object is developed. The minimum mass criterion is used in the optimization method; limitations are imposed in accordance with strength and stiffness requirements. An example is given of optimization of a typical welded portion of a high pressure compressor rotor resulting in mass reduction and

The paper studies the aircraft astro-inertial navigation system, which consists of an astronomical navigation system installed on a gyro-stabilized platform of inertial navigation system. The errors of this system arising from various disturbing factors are investigated. Methods based on system correction channels formation and using adaptive estimation algorithm are proposed for reducing these errors

Heat exchange surfaces for enhancing the heat transfer in aircraft heat exchangers are proposed. They are made in the form of periodically applied oval-arc and oval-trench dimples. The results of the primary experimental thermal-hydraulic studies of paths of different configurations are presented.

The paper presents the main results of the experimental study of acoustic characteristics of the propfan engine with a high-loaded contra-rotating open rotor. The measurements are made during the engine operation under static conditions. The power, directivity, and spectral characteristics of the power plant acoustic field are obtained.

An approach to design of the rudder—drive system taking into account the aeroelastic characteristics of the rudder is proposed. Mathematical models are developed that are used to solve problems of the rudder design parameters selection and the rudder—drive system stability analysis. An example of design of the rudder—drive system of the air-to-air unmanned aerial vehicle is given.

A criterion equation is proposed for estimating the heat generation equivalent to the total power loss for rotation of tapered roller bearings operating under conditions of the middle support of gas turbine rotors.