The formation of an image and the selection of rational engine design parameters on the example of an advanced heavy transport aircraft

The selection of rational design parameters of engines used in a promising An-124-class transport aircraft is described on the basis of the systematic integrated approach with an assessment of flight performance and acoustic indicators, as well as with consideration and minimization of technical risks. The problem was solved using a developed software package that combines mathematical models and computer routines, provides calculation of the aircraft and engine parameters, as well as flight, take-off and landing performance, taking into account acoustic limitations. A rational multi-criteria solution is presented in the form of the family of Pareto-optimal engines, several of the most preferred options are identified. Presented studies are aimed at reducing the risk of not obtaining specified aircraft characteristics, – the risk caused by the degree of uncertainty in specification of predicted indicators of the perfection of the engine and aircraft. These studies include solving a “robust” optimization problem, where the values of the targeted indicators for the accepted “confidence” level of probability were adopted as criteria.

Keywords: bypass turbojet engine, flight performance, acoustic characteristics, technical risks, Pareto set, optimization

Selivanov O.D., Fokin D.B., Ryabov P.A., Evstigneev A.A., Nyagin P.V.

Traditional, hybrid and electric propulsion systems of commuter aircrafts

The paper presents the efficiency studies of a hybrid electric propulsion system of different types, an electric propulsion system, and traditional propulsion system for 19 passenger capacity commuter airliner. The basic variant for comparative evaluation is an aircraft with a traditional propulsion system based on two turboprop engines of the H80-200 type (GEAviation Czech). The following propulsion systems are considered: a traditional propulsion system based on two turboprop engines, a serial hybrid propulsion system based on a turboshaft engine, a parallel hybrid propulsion system based on a hybrid turboprop engine (with integrated reversible electric machine), a “partially turboelectric” propulsion system consisting of two hybrid turboprop engines, one of which has its core shut off in flight, and a fully electric propulsion system. Parameters are adopted at the technological development levels of 2020 and 2030 for the simulation of the traditional propulsion system, and for the simulation of hybrid and electric propulsion systems – at the level of 2030. The following parameters are used as efficiency criteria: average fuel consumption per kilometer, energy efficiency and maximum flight range at a given take-off weight of the aircraft.

Keywords: commuter aircraft, hybrid propulsion system, turboprop engine, turboshaft engine, hybrid turboprop engine, electric propulsion system

Varyukhin A.N., Zakharchenko V.S., Rakhmankulov D.Ya., Suntsov P.S., Ovdienko M.A., Geliev A.V., Kiselev I.O., Vlasov A.V.

Influence of non-steady non-uniform total temperature disturbances on the gas-dynamic stability of the flow in a dual axial compressor of turbojet

The stability of the flow in the gas turbine compressor is influenced not only by perturbations of the full pressure, but also by total temperature disturbances. Temperature disturbances are formed in the external flow and enter the compressor through the air intake. In this article, a two-dimensional engine model is used to numerically simulate the effect of temperature disturbances. A two-shaft gas turbine with low pressure and high pressure compressors is considered. In this article the results of parametric study of dependence of critical heating value on width of zone with increased total temperature, on corrected rpm, and on rate of temperature disturbance increase are presented. Process of passing of the temperature disturbances through the compressor and transformation of the domain with increased temperature are investigated, along with disturbances of total pressure and circumferential velocity induced by this domain. Physical processes are considered for each case, critical heating values are defined.

Keywords: turbojet, gas-dynamic stability, total temperature disturbances, total pressure disturbances, transformation of disturbances passing through the engine, computation model of engine

   Arytyunov G.S.

Features of modeling GTE controllers on digital computers

Numerical calculation methods for mathematical models of hydromechanical controllers, which are used in gas turbine engine automatic control systems, are considered. They take into account the specific features of these devices and allow you to provide the necessary accuracy and speed while maintaining the stability of the computational process. Developed a fairly long time ago, the methodology given in the article is used in modern software for calculating mathematical models of controllers.

Keywords: differential equations, mathematical model, automatic control system, hydromechanical controller, integrating, integration step

Pneumohydraulic throwing device for accelerating large-sized objects in the process tests of aircraft equipment on impact with a foreign object

There is proposed the pneumatic-hydraulic method of shooting projectiles. We designed and produced the pneumatichydraulic throwing device. We have proposed a scheme for supplying compressed air to this device for its testing. There are the calculated dependences of the hydraulic jet speed on the displacement air pressure.

Keywords: impact tests, strength tests, foreign object impact, throwing device

   Kulakov V.V.,

  Petrov D.S.,
  Nikiforov V.S.,
  Safronov A.V.

Method of manufacturing a plate heat exchanger for a small-size gas turbine engine with heat recovery

A method of manufacturing plate heat exchangers for small-size gas turbine engines and gas turbine plants with heat recovery has been developed. Manufacturing of a high-temperature heat exchanger is carried out using laser technologies on a low-power machine with numerical control. A list of technological equipment necessary for the manufacture of a heat exchanger according to the proposed methodology has been compiled. The methodology was tested during creation of an experimental heat exchanger for a ground-based small-size gas turbine powerplant with heat recovery. The methodology is patented.

Keywords: small-size gas turbine engine, plate heat exchanger, laser welding

Remchukov S.S., Lebedinskii R.N.

The World-Class Research Center “Supersonic” in the field of aircraft engine development

The article presents the goals of world-class research centers and the role of CIAM in the WCRC “Supersonic”. The relevance of the problem of developing a supersonic passenger aircraft is reflected. A number of problems associated with its creation are identified, the most important of which are related to the propulsion system: high fuel efficiency, environmental noise, emission of harmful substances, engine life, and stable operation in conditions of large flow non-uniformity at the engine inlet. Research has begun in all areas, and preliminary results have been obtained. The indicators of the CIAM laboratory “Gas dynamics and propulsion system” are provided and its role in the consortium of the WCRC “Supersonic” is noted.

Keywords: supersonic, world-class research center, supersonic passenger aircraft

Lanshin A.I., Komratov D.V., Postnikov A.A.

Algorithmic improvement of accuracy in determining the conversion characteristic of a wireless digital accelerometer

The article examines specifics of determining conversion characteristics of a wireless digital vibration sensor in the entire operating frequency range. The effect of output signal sampling on the accuracy of estimatingthe vibration acceleration amplitude in the high-frequency part of the range based on measurement results obtained by a wireless digital accelerometer is shown. A modified trigonometric method for processing measurement results of sinusoidal vibration by the sensor in a full-scale experiment is proposed to determine the actual conversion characteristics of the sensor.

Keywords: wireless digital accelerometer, sensor conversion characteristic, operating frequency range, measurement results processing, measurement error

Kesselman M.G., Chernyshov V.I.