Том 62, № 1 (2019)

The influence of grid parameters variable over height on the weight of cylindrical and conical lattice shells made of carbon fiber is studied using the ANSYS software. The shells are loaded with longitudinal compressive and shear forces on the upper end face.

The paper represents the results of the experimental study on variation of the longitudinal elastic modulus and Poisson’s ratio for the carbon fiber specimens under fatigue loading at variable temperature. The approximating relations reflecting the test data are proposed.

The problem of synthesizing stabilization laws for lateral motion of a maneuverable aircraft at the lack of data on its sideslip and roll angles is analytically solved. The solution is based on the improved method of output signal control synthesis, which provides the specified spectrum of MIMO-system motion. The results of analytical synthesis of the control law and numerical simulation data are presented.

The paper attempts to solve the initial orientation task for perturbed-basis strapdown inertial navigation systems (SINS) of aircraft with most general assumptions about the character of the angular motion of the basis and the accelerations perturbing the SINS. The solution has been attained in the form of generalized Kalman filter using the vector of Rodriguez—Hamilton parameters as the state vector, and the measurement vector of the SINS accelerometers as the observation vector. A practical example serves to illustrate the high precision and convergence rate of estimation process of the aircraft SINS initial orientation parameters.

The optimization problem of heat and mass transfer in the boundary layer on permeable profiles in supersonic gas flows is considered. Unlike the previous works of this direction, the analytical formula for optimal gas flow through the permeable surface is obtained in the present work, it is more convenient for application in engineering practice. The results of computing experiment are given.

The flame tube head design is presented of the multi-injector combustion chamber of the gas turbine engine. The technique is described of determining the temperature of fuel gas flowing in the header, which is placed in the combustion chamber flame tube head. The calculation results of the fuel heating in the flame tube head are given.

For spherical layer of insulation surface, we give a solution of the linear time-dependent heat transfer problem with axially symmetric distribution of the heat flux density over the layer exterior surface. The insulation material has anisotropic heat conduction properties characterized by the ratio of the thermal conductivities along and across the layer. The solution obtained is used for qualitative estimate of the effect of this ratio on the leveling of temperature distributions for non-uniform heating specific for conditions of an axially symmetric hypersonic flow past a hemispherical blunting.

The paper considers the optimization problems in high-pressure turbine gas-dynamic design based on the ANSYS CFX software package. It is shown that the optimization procedure formation and predicted optimization results depend on the turbine dimension. The best results of the gas-dynamic optimization can be achieved, when turbines with aerodynamically long blades are designed.

The transfer of selective radiation from exhaust flames and traces of air carriers is considered taking into account an acute selection of radiation spectra and radiation absorption spectra by the atmosphere. Numerical simulation of radiation transfer reveals the effects of medium clarification or enhancement of radiation absorption by it, depending on the temperature field and chemical composition of selective radiation sources created by airborne materials in the atmosphere. The effect of the temperature shift of the centers of spectral lines at high temperatures of the air carrier flame on the transfer of their radiation in the atmosphere is noted.

The design features of the complex air data system of aircraft with a fixed flush-mounted flow receiver using integrated channels of aeromechanic measuring-computing system based on the VIMI method with the Luenberger observer are revealed. The complex system analysis technique and efficiency are considered on the example of an integrated channel for measuring the true air velocity vector parameters.

Computational research is carried out of the effect of geometric scatter within the manufacturing tolerances on the natural frequency values of a low pressure compressor blade. The first stage blade natural frequencies are estimated and compared considering various distribution laws of dimensions within the manufacturing tolerances. The joint approach to the blade natural frequency optimization and robust design is presented. The obtained blade design is less sensitive to geometric dimension scattering compared to the original design.

The paper proposes new methods and means for the process of automating technological preproduction planning based on the solution of the main management function in small-scale multi-product aircraft manufacturing companies.

A technique for constructing a model of folded core is developed taking into account the thickness of the material. The concept of the overlap coefficient and the corrugation height in the extremely compressed state are introduced.

The paper highlights the issues of methodology of GTE threaded joints assembly upon the characteristics of oscillatory processes generated in the joints by ultrasonic vibrations. The article provides the method for adaptive control of the degree of tightening of threaded joints, ensuring the ability to determine the quality of the assembly by the nature of the amplitude-frequency response.

The paper describes the research of changes in the cruise climb performance of the Il-96-300 aircraft performed while compiling materials of 2005–2015 obtained during the main flight performance assessment in the airplane example certification. The most important result of the work is the conclusion that not only the performances themselves but also the current limitations of the maximum cruise altitudes require revision, taking into account the altitude-speed performances of PS-90 engines that have changed, due to a number of modifications.

Mathematical models are obtained that make it possible to simplify the accounting for the uncertainties in the initial data values when designing a gas turbine engine in a helicopter system at the initial design stages.