Eng
Eng
RusDurability assessment of turbopump turbine wheel blades with manufacturing feature defects
The article discusses issues related to assessment of cyclic life of turbine rotor blades of a liquid rocket engine’s turbopump, considering following defects of blades: a defective surface layer, which is formed during manufacturing of turbine blades by electrical discharge machining, and lack-of-fusion defects formed during manufacturing using additive technologies.
Keywords: turbine wheel, blisk, blade, defect, number of cycles, stress, crack.
Ivanov A.V., Rudis M.A.
Simulation of an oil supply through the oil catching ring to the gas turbine engine bearings
The article presents a study of the influence of oil catching ring design and operational parameters on an oil mass flow rate through the bearings. Geometrical parameters which provide the greatest oil mass flow rate were selected and permissible technological deviations for these parameters were determined. Conducted experiments, as well as the operation of oil catching rings in the engines, confirmed their effectiveness and reliability of numerical studies.
Keywords: gas turbine engine, oil supply, oil catching ring, ball bearing, CFD.
Falaleev S.V., Boev A.A.
Numerical modeling of arc discharge in air under external magnetic field in magnetogasdynamic approximation
The mathematical model and results of numerical simulation of the plasma actuator using an arc discharge in an external magnetic field are presented in the article. To describe the process of the arc’s motion after its formation, a mathematical model was implemented based on the magnetogasdynamic one-fluid two-dimensional approximation of the equations of the hydrodynamic method for describing plasma under conditions of local thermodynamic equilibrium. An analysis of the formation and motion of vortex structures near the region occupied by hot gas is performed and a qualitative assessment of different interaction mechanisms of plasma formation and the flow through impulse generation and Joule heating is given. Results of the analysis are compared with available experimental data, as well as with calculations of other authors. A simplified source model was developed, adapted for use in multidimensional gas-dynamic calculations.
Keywords: arc discharge, plasma actuator, numerical simulation, Navier – Stokes equations, source terms.
Semenev P.A., Toktaliev P.D., Moralev I.A., Kazanskiy P.N., Bityurin V.A., Bocharov A.N.
Influence of air flow swirling in a combustion zone on axial size of a gas turbine engine
A review of studies on the influence of flow swirl on acceleration of the combustion process is presented. It is shown that the reason for the acceleration is the relative movement (lifting) of the cold mixture to the outer boundary of the combustion zone, and the hot mixture to the inner boundary or to the center of rotation. Several schemes using combustion in a swirling stream are considered: the concept of an ultra-compact combustion chamber, which offers a combined vane, which is a combination of compressor outlet vanes, combustion chamber and turbine vanes; a combustion chamber with niche stabilizers, which creates swirling movement of fuel and air; an engine based on a single coil containing a series of compressor blades with end combustion chambers and a series of turbine blades that rotate as a whole. Results of the work on the development of an integrated combustion chamber (CCI) with air flow swirling are presented. It is shown that the use of airflow swirling in the CCI scheme with modernization of a diffuser, a combustion chamber and a high-pressure turbine nozzle makes it possible to reduce the lengths of the elements by about 20...25% in comparison with existing engines elements, and therefore reduce the length of the engine itself.
Keywords: combustion chamber, nozzle apparatus, diffuser, combustion, swirling flow.
Strokin V.N., Shilova T.V.
Take-off thrust and noise control for supersonic civil transport engines
Calculated estimates of the noise levels of a supersonic civil transport at certification points are given, taking into account the main sources of engine noise – a fan and a jet. It is shown that, depending on the bypass ratio of the engines, calculated estimates of the SCT noise levels on takeoff obtained using the multi-mode engine traction control program are 2,3…6,0 EPNdB lower than the SCT noise levels obtained using the engine traction control program traditionally used on subsonic commercial aircraft.
Keywords: supersonic civil transport, engine thrust control program, engine throttle ratio and rate of thrust throttling, aircraft noise certification points.
Mirzoyan A.A., Khaletskii I.D.
Influence of the foil design in radial foil gas bearings on characteristics of stiffness and damping in the support (review)
The paper presents an overview of foil bearing designs and outlines main schemes for three generations of bearings of this type. Advantages and disadvantages of each generation are analyzed based on published experimental data. Design solutions that increase the bearing load capacity, reduce the anisotropy of stiffness characteristics, optimize the temperature mode of gas lubrication and the stress-strain state of foils are considered in the paper. An overview of designs of hybrid gasdynamic bearings with external pressurization and magnetogasdynamic bearings is presented. Performance of bearing structural elements described in patents is analyzed based on results of experimental studies found in scientific papers. Main elements, which ensure required support characteristics of foil bearings, are identified.
Keywords: foil gas bearing, dry engine, gas-static bearing, gasdynamic bearing, magnetogasdynamic bearing.
Temis M.Yu.