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Agency: Cordis | Branch: FP7 | Program: CP-FP | Phase: AAT.2010.1.1-7. | Award Amount: 3.22M | Year: 2010

In the domain of civilian aeronautics, the increasing noise restrictions around airports are a challenging problem for aircraft and engine manufacturers. Despite significant progresses since the definition of ACARE objectives, jet noise remains the main source of noise for an aircraft at take-off and many works have been dedicated to its understanding and its reduction. First generation of noise reduction devices were passive such as chevrons or mixer which enhance the mixing in the shear layers to reduce jet noise, but also decrease the engine performance during cruise. Second generation noise reduction concepts under development are active and can be switched off after take-off. ORINOCO is a small focussed collaborative project based on the cooperation between Europe and Russia and deals with advanced engine noise control based on plasma actuators. Plasma technologies have initially been developed for flow control and their first applications for jet noise reduction were confronted with technical aspects far from acoustics. This use of plasma actuators is a novel concept that requires fundamental approaches to understand the interaction mechanisms with the main jet and the resulting radiated sound. The main topic of ORINOCO is manifold and contains theoretical, numerical and experimental investigations for an efficient implementation of plasma actuators for jet noise reduction, especially on the basis of instability waves reduction. As a consequence of these fundamental considerations, most of the 13 partners involved in ORINOCO (7 European - 6 Russian) come from Academic or Research community. Several plasma actuators concepts will be studied and assessed in small scale anechoic facilities with isothermal main jet and the most promising ones will be evaluated with a heated main jet. The work performed within the project will be monitored by an Expert Panel composed by industrial members from Europe and Russia, proof of their interest on this topic.

Aleksandrov N.L.,Moscow Institute of Physics and Technology | Kindysheva S.V.,Moscow Institute of Physics and Technology | Kochetov I.V.,Troitsk Institute for Innovation and Fusion Research
Plasma Sources Science and Technology | Year: 2014

Kinetic processes in a weakly ionized non-equilibrium plasma are considered under conditions that are typical for plasma-assisted ignition/combustion and flow control. The focus is on the simulation of active species production that leads to ignition delay reduction, flame stabilization and expansion of the flammability limit of combustible mixtures. We discuss the lack of information on electron cross sections for hydrocarbons and the accuracy of widely used approaches to simulate kinetics of active species production in air and combustible mixtures. Fast gas heating after a high-voltage nanosecond discharge is studied for various gas mixtures and reduced electric fields. We analyze the effect of negative ions generated in the afterglow of a high-voltage discharge with regard to plasma-assisted ignition and plasma aerodynamics application. © 2014 IOP Publishing Ltd.

Filippov A.V.,Troitsk Institute for Innovation and Fusion Research
Contributions to Plasma Physics | Year: 2016

The influence of the outer boundary shape on the electrostatic interaction of two charged point macroparticles in an equilibrium plasma is studied within the Debye-Hückel approximation, i.e., based on the linearized Poisson-Boltzmann model. It is shown that the boundary shape has a strong influence on the electrostatic interaction between two macroparticles, which switches from repulsion at small interparticle distances to attraction as it approaches the half-length of the computational cell. It is found that in the case of dust particles arranged in the nodes of a simple cubic lattice, the electrostatic force acting on them is equal to zero; hence, an infinite simple cubic lattice of charged dust particles is mechanically stable. (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim). Copyright © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Dyatko N.,Troitsk Institute for Innovation and Fusion Research | Donko Z.,Hungarian Academy of Sciences
Plasma Sources Science and Technology | Year: 2015

At low reduced electric fields the electron energy distribution function in heavy noble gases can take two distinct shapes. This 'bistability effect' - in which electron-electron (Coulomb) collisions play an essential role - is analyzed here for Xe with a Boltzmann equation approach and with a first principles particle simulation method. The solution of the Boltzmann equation adopts the usual approximations of (i) searching for the distribution function in the form of two terms ('two-term approximation'), (ii) neglecting the Coulomb part of the collision integral for the anisotropic part of the distribution function, (iii) treating Coulomb collisions as binary events, and (iv) truncating the range of the electron-electron interaction beyond a characteristic distance. The particle-based simulation method avoids these approximations: the many-body interactions within the electron gas with a true (un-truncated) Coulomb potential are described by a molecular dynamics algorithm, while the collisions between electrons and the background gas atoms are treated with Monte Carlo simulation. We find a good general agreement between the results of the two techniques, which confirms, to a certain extent, the approximations used in the solution of the Boltzmann equation. The differences observed between the results are believed to originate from these approximations and from the presence of statistical noise in the particle simulations. © 2015 IOP Publishing Ltd.

Likhanskii V.,Troitsk Institute for Innovation and Fusion Research | Kolesnik M.,Troitsk Institute for Innovation and Fusion Research
Corrosion Science | Year: 2014

Undulations of metal/oxide interface were determined in experiments during oxidation. Such structure can cause cracking near metal/oxide interface when a critical thickness of oxide film has been achieved. Cracking of the oxide leads to increase of metal oxidation rate and changes the oxide growth kinetics. In this paper conditions of the periodic structure parameters evolution have been determined based on minimization of mechanical stress energy appearing in the oxide film and the metal during oxidation. It has been shown that the process leading to increase of the wavelength near metal/oxide interface during oxidation can be the effect of period doubling bifurcation. © 2014 Elsevier Ltd.

Munirov V.R.,Troitsk Institute for Innovation and Fusion Research | Filippov A.V.,Troitsk Institute for Innovation and Fusion Research
Journal of Experimental and Theoretical Physics | Year: 2013

The electrostatic interaction of two charged dielectric spherical particles with a nonuniform freecharge distribution over their surfaces in an external homogeneous electric field is considered. An exact solution for the electric field potential is obtained, and an analytical expression for the interaction force between these two particles is found. The case of a uniform free-charge distribution is considered in detail, and the region of parameters in the plane "the ratio of the radii vs. the ratio of the charges," where repulsion between two like-charged particles turns into attraction as the interparticle distance decreases is established. © 2013 Pleiades Publishing, Inc.

Napartovich A.P.,Troitsk Institute for Innovation and Fusion Research | Kochetov I.V.,Troitsk Institute for Innovation and Fusion Research
Plasma Sources Science and Technology | Year: 2011

The non-thermal plasma is a key component in gas lasers, waste gas cleaners, ozone generators, plasma igniters, flame holders, flow control in high-speed aerodynamics and other applications. The specific feature of the non-thermal plasma is its high sensitivity to variations in governing parameters (gas composition, pressure, pulse duration, E/N parameter). The reactivity of the plasma is due to the appearance of atoms and chemical radicals. For the efficient production of chemically active species high average electron energy is required, which is controlled by the balance of gain from the electric field and loss in inelastic collisions. In low-ionized plasma the electron energy distribution function is far from Maxwellian and must be found numerically for specified conditions. Numerical modeling of processes in plasma technologies requires vast databases on electron scattering cross sections to be available. The only reliable criterion for evaluations of validity of a set of cross sections for a particular species is a correct prediction of electron transport and kinetic coefficients measured in swarm experiments. This criterion is used traditionally to improve experimentally measured cross sections, as was suggested earlier by Phelps. The set of cross sections subjected to this procedure is called a self-consistent set. Nowadays, such reliable self-consistent sets are known for many species. Problems encountered in implementation of the fitting procedure and examples of its successful applications are described in the paper. © 2011 IOP Publishing Ltd.

Filippov A.V.,Troitsk Institute for Innovation and Fusion Research
Journal of Physics: Conference Series | Year: 2015

This paper is devoted to a careful study of two charge interaction in an equilibrium plasma within the Debye approximation. The effect of external boundary conditions for the electric field strength and potential on the electrostatic force is studied. The problem is solved by the method of potential decomposition into Legendre polynomials up to the fifth multipole term included. It is shown that the effect of attraction of identically charged macroparticles is explained by the influence of the external boundary. When the size of a calculation cell is increased the attraction effect disappears and the electrostatic force is well described by the screened Debye-Hückel potential. © Published under licence by IOP Publishing Ltd.

Samokhin A.A.,Troitsk Institute for Innovation and Fusion Research
Plasma Physics Reports | Year: 2010

An efficient numerical code for simulating the propagation of a high-power electromagnetic pulse in a vacuum transmission line is required to study the physical phenomena occurring in such a line, to analyze the operation of present-day megavolt generators at an ̃10-TW power level, and to design such new devices. The main physical theoretical principles are presented, and the stability of flows in the near-threshold region at the boundary of the regime of magnetic self-insulation is investigated based on one-dimensional telegraph equations with electron losses. Numerical (difference) methods-specifically, a method of characteristics and a finite-difference scheme-are described and their properties and effectiveness are compared by analyzing the high-frequency modes. © Pleiades Publishing, Ltd., 2010.

Samokhin A.A.,Troitsk Institute for Innovation and Fusion Research
Plasma Physics Reports | Year: 2010

Studies of physical phenomena in magnetically insulated transmission lines (MITLs) of high-power pulsed current generators, analysis of operation of existing megavolt generators, and designing of new high-current generators with a power of up to ~10 TW require creating an efficient numerical code for modeling the propagation of a high-power electromagnetic pulse in an MITL. This paper presents basic theoretical concepts of MITL operation in the framework of telegraph equations with allowance for electron leakage and variations in the electrode emissivity and analyzes propagation of an electromagnetic wave in the MITLs of the ANGARA-5-1 eight-module facility toward a dynamic load installed in the central unit with a matrix inductance. © 2010 Pleiades Publishing, Ltd.

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