


卷 60, 编号 3 (2017)
- 年: 2017
- 文章: 24
- URL: https://journals.rcsi.science/1068-7998/issue/view/14232
Aero- and Gas-Dynamics of Flight Vehicles and Their Engines
Numerical scheme of the second order of accuracy for vortex methods for incompressible flow simulation around airfoils
摘要
A high-accuracy numerical scheme is proposed for vortex methods of flow simulation around airfoils of arbitrary shape including airfoils with sharp edges, because it does not require the solution continuity on the airfoil.



Impact of a cavitation bubble on a wall
摘要
Impulse action of a cavitation bubble on a rigid wall is studied depending on the distance between them. We determine the distances at which the periphery pressure maximums on a wall are preserved as well as the distances at which these maximums exceed the water hammer pressure.



Influence of the disperse phase properties on characteristics of the shock wave passing the direct shock from pure gas in the gas mixture
摘要
In this paper, a mathematical model of the nonequilibrium multiphase medium dynamics based on a two-speed two-temperature approximation of interpenetrative continuum mechanics is used to describe the nonstationary processes in a gas suspension. The influence of particle size and their volume content as well as the true density on the process of distributing a shockwave of pure gas into a gas suspension was investigated by means of numerical modeling.



Aircraft Equipment
Application of a discrete-continuous model of strength analysis to solve the identification problem of a thermally loaded structure
摘要
This paper proposes to solve the problem of determining the strength properties of materials for thin-walled structural elements under mechanical and thermal loading as an optimization problem. A mathematical statement of the problem under certain assumptions is given.



Flight Vehicle Design
Algebraic operations on graphs with using numeric coding for simulating the systems of rocket and space technology
摘要
The paper adduces the relators for algebraic operations on graphs using the numeric codes of the graphs. The special algebra of codes has been devised with consideration of the principles of graph transformation. This paper demonstrates the relevance of numeric coding of graphs for solving the problems of enumeration, systematization, and compact representation of the information about the structural and functional characteristics of the systems of flow distribution and conversion of rocket and space technology and for conducting the modeling transformations of given systems in the course of the structural and functional studies as well.



Methodological foundations and areas for improvement of the aircraft design process
摘要
The paper considers the methodological foundations of aircraft design facilitated by advanced information technologies. We outline some promising areas of project management perfection and methods of solving the problems at all stages of the aircraft life cycle.



Structural Mechanics and Strength of Flight Vehicles
Drop test simulation for a helicopter tail landing gear
摘要
The paper describes a mathematical model of drop tests on the landing gear of the Ka-62 helicopter. The model is formulated using the multibody system simulation procedure based on the Lagrange equations of the first kind.



Flight Dynamics and Control of Flight Vehicles
Formation of programmed spatial flight trajectories of unmanned aerial vehicles
摘要
In this paper, we introduce a concept of coordinated turn that means the application of the lifting force being perpendicular to the UAV velocity vector and parallel to the surface on which the exact point target is located. Analytical solutions of the corresponding differential equations of the coordinated turn are derived.



An efficient algorithm of data smoothing in real-time calculations
摘要
We propose an algorithm for real-time data smoothing due to considerable reduction and simplification of computations by employing the recursive least mean squares technique. The efficiency of algorithms is shown by an example of determining the flight airspeed and altitude based on the data of pressure sensors.



Method of designing a neural controller for the automatic lateral control of unmanned aerial vehicles
摘要
The paper discusses a method of designing the neural controller for two-channel control of a technical object by an example of the roll and yaw control depending on deviations, velocities and accelerations of their variation.



Special features of forming the provoking probing signal in implementation of the semi-passive homing method for mobile objects
摘要
The paper considers some theoretical aspects of implementing the semi-passive homing method for mobile objects by an example of radar-based systems.



Analysis of the spacecraft vertical landing dynamics on the platform with crash legs
摘要
This paper proposes a novel landing gear for spacecraft that allows a weight reduction due to using deformable crash legs. Numerical simulation of the landing process was performed.



Aircraft and Rocket Engine Theory
Investigation of the loop combustion chamber
摘要
As a result of the experimental-theoretical study of the loop (countercurrent) combustion chamber of the gas turbine engine, the data and theoretical dependences are obtained on the change in the combustion completeness and combustion temperature in various operating modes.



The adjustment of the mathematical model accuracy of the gas-hydraulic flight control actuator power circuit of an aircraft
摘要
The methodology is proposed and the mathematical model is developed for the purpose of numerical simulation of the power circuit of the gas-hydraulic actuator with displacing power source for the gimbaled nozzle control. It provides the highest power efficiency factor of the actuator as a part of aircraft by means of pulling together the profiles of available and required power.



Calculation of low cycle fatigue life for gas-turbine engine critical parts
摘要
The paper presents a technique of calculating the life for gas turbine engine parts in a low cycle area based on the influence coefficients taking into account analytical and operational factors. A statistical method is used to determine the influence coefficients.



Computation of design parameters influence on air injector fuel atomization
摘要
A technique for calculating the two-phase flows at liquid fuel atomization by the air injector is developed. In the course of numerical experiments, the flow parameter distributions over the cross section and volume for different nozzle design options are obtained. The influence of the twist angle of the gas flow on the liquid fuel atomization is analyzed.



Fuel atomization and mixing in unsteady swirling flows behind the gas-dynamic stabilizer
摘要
Features of fuel atomization and propagation in the flow behind a gas-dynamic stabilizer are considered. Estimations of the influence of transverse jets impulse magnitude on characteristics of mixing behind the stabilizer are obtained by numerical and experimental methods.



Study of performance of the aircraft gas turbine engine integrated with a gas dynamic laser
摘要
We consider a turbofan engine (TFE), where the turbine rotor blades of the low pressure turbine (LPT) are micro-Laval nozzles. We demonstrated the possibility of integrating the super jet turbine and a jet nozzle as a single binary system for the purpose of generation of powerful coherence radiation. We estimated the efficiency of the binary high pressure emitting system being a TFE part.



Mechanism of transport phenomena at low pressures
摘要
The analogy of molecular flows of gases, molecular heat transfer, and radiation heat transfer in transparent mediums is established.



Aircraft Instruments and Instrumentation Computer Complexes
Ensuring the electromagnetic compatibility of onboard cables for unmanned aerial vehicles
摘要
The paper presents the results of studying the shielding efficiency for onboard cables of unmanned aerial vehicles (UAV). We specify the special features of studying the shielding efficiency for the onboard cables by means of a coaxial setup on frequencies more 3 MHz. The results presented in the paper experimentally verify that the shielding efficiency for onboard cables depends on the type of electromagnetic interference.



Construction and algorithms of a helicopter air data system with aerometric and ion-tagging measurement channels
摘要
A functional diagram of the air data system and a structural scheme of the air data sensor are described. The special features of generating and processing the air data of aerometric and ion-tagging measurement channels at parking, takeoff and landing modes of the helicopter operation are examined.



Technical Notes
A method of determining the aircraft motion parameters at landing
摘要
The paper contains a method of determining the aircraft motion parameters at landing based on the application of the ground optoelectronic system. The method proposed provides the certification of present-day instrument landing systems.



Aircraft and Rocket Engine Design and Development
Comparison of two configurations of a starter-generator integrated into the aircraft engine
摘要
An optimal design of the starter-generator integrated into aircraft engines is studied. The authors give a review for modern designs and technical solutions of the problem.



Quality assurance of spark plugs production for piston engines at the life cycle stages
摘要
The quality requirements to a technological process of producing the spark plugs are analyzed. The controlled and uncontrolled parameters of spark plugs, which affect the ignition and starting quality, are identified. An approach to development of the decision support system structure for life cycle of spark plugs is described.


