Vol 10, No 3-1 (2011): Special Issue

Evaluation of the stability of GTE compressor is provided in the measurement of pressure fluctuations in the frequency range from several Hz to several kHz. Because the sensors of the pressure fluctuations can not be located at the measurement points due to excessive heat, vibration and limited space for their installation used the lead-in channels - acoustic probes. Proposed science-based methodology for calculating the frequency characteristics of the probes with corrective elements on which the developed software tools to select their parameters. The developed software can process the information derived using acoustic probes during engine tests. To verify the validity of computational models of probes at the Department of SNPP SGAU established test facilities and measurement and registration set in place to test their frequency.

Low-cycle fatigue is well researched in terms of uniaxial test experiments of plane and cylindrical specimens. At the same time material particles can be deformed at product operation under laws that differ from uniaxial test. It requires the definition of conditions of plasticity and limiting state for spatial deformation processes. This definition should consider singularities of low-cycle fatigue process: Bauschinger effect; estimations of material fault probability in a work of internal force. With this design the approach to construction of new plasticity condition is formulated and theoretically proved as loading surface which connected with level lines of surface of state of strain of incompressible rigid-plastic body. Use of tensors of finite strain as a measure of strain and description of Bauschinger effect with help of these tensors is main difference of suggested approach.

Examines the influence of burner design, the main characteristics of the combustion chamber. These activities were carried out in order to improve the environmental performance of gas turbines, which significantly reduce toxic emissions in comparison with the serial main combustor

Flutter of jet engine compressor blades is modeled using a new approach based on energy method. Flutter calculations of 1st and 2nd compressor stages are conducted for different engine regimes and different boundary conditions at mid-span shroud. Results are verified by experimental data. This method can be applied for blade flutter modeling and suppression of novel engine designs.

In article the analysis of features of process of cutting of female threads by a tap in deaf apertures is carried out. On the basis of the given analysis researches of influence of the compelled ultrasonic fluctuations on a twisting moment, arising in the initial moment of an exit of a tap from an aperture are conducted. It is established that in case of processing with ultrasonic fluctuations of Mkr at an exit of a tap it is much less, than at usual cutting of a carving. By results of the done researches the way нарезания carvings with the ultrasound is offered, allowing to raise working capacity.

The analysis of the factors defining value of ecological and economic indicators of internal combustion engines is presented. The technical decisions directed on achievement of demanded indicators of quality of functioning, as that an internal combustion engine on a basis сrank a rod the mechanism with the dual kinematic communications, possessing the improved ecological characteristics, in high mechanical efficiency, and also in the improved kinematic and dynamic parameters based on realization of a progressive thermodynamic cycle with high degree of expansion and with «internal cooling» are offered.

Disposable unmanned aircraft vehicle propulsion system features are discussed. The dynamic characteristic is proposed to generate control program for disposable unmanned aircraft vehicle propulsion system. The simulation system Dvigwp is used to calculate dynamic characteristic of turbojet engine. The control program, which provides minimal time of transient process is generated by means of calculated dynamic characteristic.

Results of numerical simulation of viscous compressible gas in counterflow burner unit, taking into account characteristic features of flow in bounded swirling flow diaphragm walls. The calculations are performed using models of turbulence: SST, ke, RNG ke, EARSM, RSM BSL. It is shown that in the case of the Reynolds stress transport model structure of the flow has the features do not appear when using the standard two-parameter models of turbulence, but observed during the experiments.

In this article, using of heat recovery technology for improving the efficiency of power plants and compressor station is scientific and technically justified. In addition, the technical and economical feasibility of the proposed methods based on the thermodynamic and gas-dynamic calculations of existing gas turbines and combined-cycle plant is traced, considering the introduction of the investigated methods of improving efficiency.

It is presented the results of investigation of combustion chamber’s gasdynamics. It’s obtained criteria equations to perform an optimization of its parameters relatively to minimal hydraulically losses on the stage of diffusion’s designing.

Investigation multi-fields method is developed for estimation of finger seal performance. This method is comprised gas flow simulation and stress-deformed analysis. Mathematical models have different level of refinement and can be used both for fast optimizations and full analysis of the finger seal.

Modern concepts of using optimization technologies for structural design are considered. Several approaches of optimization problems for fan and compressor stages elements are considered. The problem of blade and disk optimization and the problem of total stresses minimization under certain constraints are investigated. All results were obtained using developed FE analysis program connected with SQP optimization procedure.

New directions in the field of a detonation dusting of firm wearproof coverings are described. Results of research mechanical and tribotechnical properties nanostructured composite ceramic-metal coverings are resulted. The scope of detonation coverings in the industry is shown in the article.

In article results of working out of a universal programme-hardware complex for research mechanical, geometrical and tribotechnical properties of surfaces of samples of materials and details of machines are resulted.

This paper investigates the effect of radial location of the inlet nozzles on effectiveness Θ and total pressure losses ζ of pre-swirl systems. A commercial code Ansys CFX is used to solve the Reynolds Averaged Navier Stokes (RANS) equations using SST turbulence model with wall functions approach. Computations are performed for the flow parameter 0.375 < < 0.75 Т λ , rotational Reynolds number 1.69⋅10⁷ < Re_Ф < 2.33⋅10⁷ , throughflow Reynolds number or non-dimensional mass flow rate 2.79⋅10⁷ < C_w < 5.73⋅10⁷ and swirl ratio 0.548 < β < 2.5 . The principles of the most appropriate radius were developed. Also the problem of heat exchanger was discussed.

The results of numerical and experimental study of heat transfer and gas dynamics in the vortex energy separator were presented. Examples of the cooled nozzle blades with built-in vortex tube.

On the basis of the method insignificant deviations and the compressor characteristics presentation forms as a polynomial there has been worked out and tested methods of the parametric identification compressors and fans mathematical models according to the results of the gas turbine engine development test.

The results of the study of ultrasonic hardening of free samplesfrom the balls of titanium alloys. Shows the effect of ultrasound on the physical, mechanical and operational characteristics.

Results of tests on short-term strength and low-cycle fatigue specimens with "trivalent" and standard chrome, the results of fractographic researches chrome samples are represented. By vacuum extraction determined content of the hydrogen in the Cr(III) coating.

The article presents the results of construction steels study by the acoustical, optical, eddy current and magnetic methods of NDT. The ways of assessing of the degradation degree of material in the early stages of fatigue failure and the stress condition of material were suggested.

Article is devoted development of system-simulator exterior loadings operating on steering organs. In article the system-simulator functional scheme, the general device, a principle of functioning, inspects and adjustable parameters also are resulted.

The results of an experimental study of heat transfer enhancement in channels of the cooling nozzle blade with cyclone-vortex cooling system are analyzed. The regularities of change of temperature fields and heat transfer coefficient on the surface of the cooling channels, depending on the number of the leads at different tangential pressure drops is established. Obtained criteria function for determining the heat transfer coefficient on the inner surface of the cooling channel nozzle blade with cyclone-vortex cooling system.

The operation of ejectors is well known, however no models are available in modern performance synthesis tools. For designing an engine the effect of an ejector on the operation of a turbine aero engine and vice versa is of interest. Therefore the development of a module for caclulation of ejector performance on a turbine aero engine with a convergent primary nozzle for application in a performance synthesis tool is described. The module is to allow a flexible representation of ejectors and an appropriate consideration of the operation in performance synthesis. Initially a simplified mathematical 1-D model of the ejector nozzle is presented. It is valid for a lossless, compressible flow of an air/combustion gas mixture. The model is able to solve the flow equations for complete mixing of primary and secondary flows in case of both subcritical and supercritical primary nozzle flow.

Integration of the model with the performance synthesis programme SAEPP (Sophisticated Aero-Engine Performance Program) as well as the iterative approach to solving the equations is described. Example calculations are performed at selected operating points of the micro gas turbine engine ILA001 and compared to the results without ejector. The subsequent discussion of the results shows that the model which thus far was lossless needs to be expanded to consider inlet, mixing and friction losses in ordner to correctly reflect the operating behaviour of an ejector.

The technical devices for creating of sportive and informative sound in car passenger compartment are considered. It is shown that the controlled sound transmission from engine intake system into the salon is one of the most perspective ways of sportive and informative sound generation. The acoustical-mechanical devices (impressors), methods of their synthesis and development and are also considered.

The consideration of solid oxide fuel cell's calculation algorithm to raise the possibilities of program complex DVIGwT. The results of testing SOFC's calculation research were compared with experiment's results. Combined power installations; solid oxide fuel cell; steam-water conversion; structural – parameter synthesis and analyses.

For the convergence of the computational model the formation and decomposition of nitrogen oxides in exhaust gases from the experimental data should take into account changes the volume of combustion. Since this change is the parameter that determines the flow of the combustion process.