UDK 629.735.33.015 BBK 39.15

Kirenchev A. G.

Danilenko N. V.

The article deals with the issue of possible vortex activation of the working process of the wing thrust over the underlying surface. The useful effect of this working process can manifest itself in reducing the aircraft take-off and landing roll in the field of wing vortex interference with the airfield ground. The area of practical use could cover the lifting surfaces of hydrofoil crafts, ram-wing crafts and similar vehicles at low flight altitudes. The vortex activation of the wing thrust is based on the professor N.Ye.Zhukovskiy’s theorem about the wing lift and the mirror effect of the underlying surface proposed by Prandtl. The authors defined the physical and kinematic essence of interference of a linear vortex with a flat underlying surface.  The effect of that kind of vortex interference is represented due to comparison of auto-travel of vortex smoke rings having a different diameter and generated by an identical force pulse. The authors stated the fact of force interaction between a vortex ring and a hard flat wall which forms the basis of the method of vortex activation of the wing thrust capable of reducing the drag. As an object of theoretical research the linear infinitely long vortex of intensity Г = 2p  allowing the mathematical expression of Biot-Savart law to be reduced to the function of vortex velocity с_в = f (1/(2h)). The kinematic vortex characteristic is represented as a dependence of travel speed on the height of its position above the screen. The article identifies the main consequences of vortex and screen interference and areas of their application.

Key words: thrust, circulation of velocity Г, vortex interference, flat screen, vortex travel, vortex characteristic.

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UDK 621.45.022 BBK 39.55

Skorobogatov S. V.

Isaev A. I.

With each passing year, the operational requirements for the aircraft power plants are getting stricter and stricter. The combustion chamber as one of the main parts of an aircraft engine determines the indicators of its efficiency, reliability and environmental compatibility. The indicators can be improved due to taking into account the operational requirements at the stage of designing a combustion chamber.

As the concept of a combustion chamber with a lateral system of reverse current area formation implies presence of a number of thin-walled elements as well as double-curved surfaces, designing a chamber of such construction is a complex engineering problem.

The article describes a technology of manufacturing a combustion chamber of the desired design on an example of experimental model for a chamber stand.

Key words: combustion chamber, aircraft gas-turbine engine, operational features, technology of manufacturing, combustion process.

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UDK 629.7.036.3 BBK 39.15

Kirenchev A. G.

Danilenko N. V.

The article considers the basic problems of vortex formation phenomenon and its natural and technogenic vortices. A new definition of vortex formation based on the physical essence of the working process is given. The mathematical foundation of the working process of vortex formation is presented with the use of Professor N. E. Zhukovsky’s theorem about the lifting force of the wing, as well as the equation for conservation of the gas movement energy and the Stokes theorem about the equality of the vortex tension and velocity circulation. Due to the analysis of the energy conservation equation the main factors of generation and accumulation of natural and technogenic vortices are revealed. The issue of the determining role of the underlying surface for forming effluent vortices of air intakes of aircraft gas-turbine propulsion systems is investigated. Influence of other external factors on the formation of technogenic vortices is noted. Classification of technogenic vortex formation and its vortices by the essence of the working process is given.

Keywords: vortex formation, technogenic vortices, vortex interference, the role of the underlying surface, gas turbine power plants, mathematical justification of Coriolis force vortices, air intake.

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