K. N. Volkov

• Kingston University

An experimental study of the ignition and combustion of a combustible propane–air mixture is carried out. The efficiency of two systems for igniting a combustible gas mixture is compared: a traditional technology using conventional spark plugs and a new system based on initiated streamer microwave discharges. The design features of a setup for crea...

The possibility of implementing a pulse-periodic process in the constant volume cavity is considered. The process is simulated using numerical solution of the equations of gas dynamics and heat transfer. In the computational model, the temperature fields in the gas and the shell material are coupled. The gaseous medium is described with a compressi...

The study is dedicated to the peculiarities of implementing the flux limiter of the flow quantity gradient when solving 3D aerodynamic problems using the system of Navier–Stokes equations on unstructured meshes. The paper describes discretisation of the system of Navier–Stokes equations on a finite-volume method and a mathematical model including S...

Numerical simulation of hydrodynamic processes accompanying the formation and propagation of vortex rings produced by a piston generator has been performed. The influence of the characteristics of a vortex ring on the transfer of a passive impurity is considered. Numerical calculations were carried out using nonstationary Navier– Stokes equations a...

Numerical modeling of the underwater outflow of a supersonic gas jet in a three-dimensional non-stationary formulation is carried out using an eddy-resolving approach based on a combination of RANS-LES turbulence modeling methods. The calculation of the interaction of a gaseous medium with a liquid is carried out using the VOF multi-phase model, th...

The generation of noise by the flow of a compressible viscous gas over a circular cylinder as a result of the formation of vortices in it and the separation of them from the surface of the cylinder was considered. The sound field of this flow was calculated using the method of simulation of large vortices, and its acoustic characteristics were dete...

The study of ignition of flammable mixtures by a microwave discharge is of interest for the design of propulsion systems with increased reliability and possibility of the use of lean fuel/air mixtures. A mathematical model for estimating plasma heating and conversion caused by a microwave subcritical streamer discharge is developed. Pressure of the...

Based on the data of a physical experiment, the possibility of increasing the efficiency of combustion of fuel in power plants with the use of a multipoint plasma ignition of a fuel mixture in a cylindrical combustion chamber of such an installation by a subcritical streamer discharge initiated on the combustion chamber surface by a half-wave reson...

Pulsed detonation engines are considered to be the promising e¨ective propulsion systems for future space missions. The ignition system has always posed problems in commercial applications. Many experimental, theoretical, and numerical studies have been performed for the past years and various ignition systems (e. g., electric discharge, microwave...

The subsonic and supersonic gas jets emanating from a conical nozzle into an immersed space were investigated. The influence of the difference between the total pressure at the inlet of the nozzle and the static pressure in the surrounding medium on the structure of such a jet and its flow dynamics and acoustics were determined and the noise level...

A simulation of the vibroacoustic processes proceeding in a long pipe with an obstacle in the form of a circular cylinder, in which a fluid flows, has been performed with regard for the action of the vortices formed downstream of the cylinder on the dynamics of the system. On the basis of the computational procedure developed, the vibroacoustic cha...

The aim of the work is to study the possibilities provided by new information technologies, object-oriented programming tools and modern operating systems for solving boundary value problems of continuum mechanics described by partial differential equations. To discretize the basic equations, we applied the method of finite differences and finite v...

The inuence of non-equilibrium kinetic processes on macroscopic parameters in air flows is a challenging and an important problem. Particularly, simulation of flows with high-temperature effects is important near the surface of spacecraft or meteorites when they enter the Earth’s atmosphere. Non-equilibrium flows of a reacting five-component air mi...

The influence of the screen size on the air breakdown by aninduced subcritical streamer discharge is discussed based on the data ofphysical and computational experiments. A cylindrical metal vibratormounted at a certain distance from the screen is used to initiate a streamerdischarge. The initiator length is comparable with the half wavelength ofel...

Direct numerical simulation of a fully developed turbulent flow of a viscous compressible fluid containing spherical solid particles in a channel is carried out. The formation of regions with an increased concentration of solid particles in a fully developed turbulent flow in a channel with solid walls is considered. The fluid flow is simulated wit...

Various electrodynamic models of a combustion chamber, in which an initiated subcritical streamer discharge is used to ignite a combustible mixture, are considered. To localize the discharge in the working chamber, discharge initiators are used based on half-wave electromagnetic vibrators with resonant properties. The dependences of the structure o...

The possibilities of organizing a repetitively pulsed process with given frequency characteristics in a cavity of constant volume with an external energy supply to the working gas mixture are considered. Modelling of gas-dynamic and thermal processes is carried out using the numerical solution of the conjugate heat transfer problem. The gas medium...

Features of the simulation of the thermodynamic and gasdynamic processes occurring in devices for reducing the noise level of a shot from a gun were considered. A simulation of large vortices in the nonstationary turbulent flow of powder gases in a muzzle noise reduction device with a silencer representing a shaped channel with several chambers, wh...

The initiation of a shock wave in the gas space of a pulse generator, the exit of this wave from the generator nozzle, and the formation of a nonstationary gas-jet flow downstream of the nozzle exit section were experimentally investigated and numerically simulated as applied to the installations for the gas-pulse cleaning of heat transfer surfaces...

Possibilities for using general-purpose graphics processing units to simulate compressible gas flows are discussed. Consideration is given to different schemes of computation of flows through the faces of the flow control volume and to the features of their implementation on graphics processing units. A solution of a number of model problems of gas...

A numerical simulation of a nonstationary flow of a gas containing inert particle in a shock tube has been perfumed on the basis of the model of mutually penetrating continua, in which the gaseous and dispersed phases are defined by sets of mass, momentum, and energy conservation equations and the equation for the evolution of the dispersed-phase v...

Super- and hypersonic flow around aircraft elements is accompanied by the formation of a complex flow structure, which is characterized by the presence of strong shock waves, rarefaction waves, contact discontinuities, separation and reattachment of the flow. For such problems, the interaction of shock waves with viscous boundary layers is characte...

The influence of the geometric and regime parameters of a resonance infrared jet-edge generator on the formation, in its resonance tube, of a sound field with a predominant discrete tone at the fundamental frequency of the generator resonant cavity was investigated. A parametric investigation of the self-sustained oscillation processes arising in t...

A sub-critical microwave discharge is used to achieve a stable ignition and combustion of lean air-fuel mixtures in a long tube. The microwave discharge is burnt at the presence of initiator with the quasi-optical microwave beam. The resonance way of initiation of a microwave discharge is more effective compared to traditional plasma-assisted ways...

Problems on the development of mathematical models for control of the technological processes of producing powders of metals from their melts and for optimization of these processes were considered. A numerical simulation of the solidification of melt droplets in a turbulent cold-gas jet has been performed with the use of a complex mathematical mod...

The atmospheric composition behind a normal shock ahead of a hypersonic vehicle differs from the atmosphere ahead of the shock. Various models of air equilibrium composition are compared, analysis of areas of these models applicability is performed. Numerical simulations of flow in a channel with a step are performed using models of perfect gas and...

The design of a subsonic jet-edge rod generator of the Hartmann-type oscillator and a scheme of measuring its acoustic parameters are presented. In this generator, unlike the Hartmann oscillator, not a cylindrical gas jet but an annular gas jet, moving along the thin cylindrical rod positioned at the axis of the generator nozzle, is used. A paramet...

Aluminized composite propellant used in solid rocket motors contain a lot of aluminium particles because high combustion energy is generated and propulsion efficiency increases by burning aluminium particles. The combustion of aluminum occurs in a significant portion of the combustion chamber and produces aluminum oxide smokes and residues that are...

A stabler ignition and combustion of the premixed air/fuel mixture remains a topic of great interest due to the high demand for effective and efficient propulsion systems in aerospace applications. Extensive experimental studies and numerical simulations have been carried out to understand and develop ignition systems using cold and non-thermal pla...

Numerical simulation of aerodynamic problems using an algorithm, which identifies shock regions and refines the mesh there using an adaptive mesh refinement method, is performed. The static mesh adaptation method is based on cell partitioning by adding new nodes to cell faces. The method of identification of the shock regions using a pressure and d...

When gas flows at a high speed in a channel with a variable cross sectional area and high-intensity energy supply, it experiences complicated physical and chemical processes producing high-temperature gas effects. High-temperature gas effects are a key issue related to design and optimization of nozzles of plasmatron of alternating current. The fin...

A simulation of a high-temperature air flow in a nozzle with a nonstationary local power supply has been performed. The thermodynamic processes in this flow were simulated using an approximate model of equilibrium air thermodynamics. Results of a numerical simulation of one-dimensional flows in nozzles with a moving powersupply zone, used in altern...

When hypersonic vehicle travels in the atmosphere with a high speed, the surrounding gas experiences complicated physical and chemical processes producing high-temperature gas effects. High-temperature gas effects are a key issue related to hypersonic aerodynamic design and optimization. The finite volume method is applied to solve unsteady three-d...

The mathematical models and computational tools for design, analysis and predictions of supersonic jet and nozzle flows in the aerodynamic windows of high-power gas lasers are considered. The steady-state Euler equations describing strong shock waves, contact discontinuities, rarefaction waves and their interactions are solved with the finite-volum...

There have been consistent efforts in developing more efficient combustion for propulsion systems. Ignition and combustion control using cold and non-thermal plasma in microwave discharges have become a major topic of interest. In this study, a microwave subcritical streamer discharge is used to initiate ignition and combustion of premixed air/fuel...

A numerical simulation of gas flows in the nozzle of an alternating-current plasma generator with a nonstationary local energy supply has been performed. The nonstationary gas flows in the plasma-generator nozzle with a highpower energy supply were simulated using the finite-volume method and the vectorized approach to the calculation of flows. Res...

The interaction of solid particles with vortex structures was investigated, and the scattering of such particles by a combined vortex was numerically simulated using the Euler–Lagrange approach. The concentration distributions of particles in the region of a gas flow occupied by a vortex at different instants of time have been obtained. The depende...

The numerical simulation of gas-dynamic processes accompanying the transverse injection of a gas jet into the supersonic part of a nozzle is considered in the context of creating steering forces in rocket engines. Numerical calculations are conducted based on various turbulence models at different mass flow rates of the injected gas. The calculatio...

The use of general purpose graphics processors for the numerical solution of problems in dynamics of viscous incompressible fluid is discussed. Specific features of the parallel implementation of the splitting scheme (projection method) are considered. The system of difference equations produced by the discretization of Poisson’s equations for pres...

The formation of regions with a higher concentration of solid particles in the completely developed turbulent flow in a channel with impermeable walls was investigated. A gas flow was simulated on the basis of nonstationary three-dimensional Navier–Stokes equations. The discrete-trajectory approach was used for simulation of the movement of particl...

Streamers are non-thermal filamentary plasmas developing in insulating mediums under the influence of strong external electric fields. Understanding of streamer propagation mechanism is of essential importance for the studies of electrical breakdown phenomena and their related applications. The study focuses on investigation of possibilities of use...

The coupled fluid/solid heat transfer computations are performed to predict the temperatures reached in the rotating disc systems. An efficient finite element analysis (FEA) and computational fluid dynamics (CFD) thermal coupling technique is developed and demonstrated. The thermal coupling is achieved by an iterative procedure between FEA and CFD...

Modelling and simulation of interaction of laser pulse with individual liquid droplets are of crucial importance in terms of development and code coupling for simulation of laser propulsion and detonation in gas-droplet systems. These applications are challenging and complex for many reasons, one among them is the disparate time and length scales t...

The optical aberrations induced by turbulent compressible flows are a serious concern in airborne communication, imaging and optical systems because the quality of the laser beam degrades due to variations of the index of refraction along its path. The aero-optical aberrations produced by compressible flows are a direct consequence of the detailed...

An algorithm for improving the scalability of the multigrid method used for solving the system of difference equations obtained by the finite volume discretization of the Navier–Stokes equations on unstructured grids with an arbitrary cell topology is proposed. It is based on the cascade assembly of the global level; the cascade procedure gradually...

A numerical simulation of a supersonic two-dimensional gas flow into which a gas jet is injected from the surface of a fl at plate along the normal to it has been performed. The calculations were carried out using the Reynolds-averaged Navier–Stokes equations closed by the SST model of turbulence. The influence of the pressure ratio of the jet on t...

Pulse detonation engines are considered to be one of effective propulsion systems for future space missions. Significant efforts are being spent on acceleration of fuel combustion and rising is efficiency. Existing studies have mainly focused on optimizing fuel injection and mixing, repetitive initiation of detonation and integration of detonation...

The transverse injection of a pulsed jet into a supersonic flow for thrust vectoring in solid rocket motors is investigated. The gas flow through the injection nozzle is controlled by a piston which performs reciprocating motion. Reynolds-averaged Navier–Stokes equations and the (k–ε) turbulence model equations are discretized using the finite volu...

Two-phase systems that involve gas-particle or gas-droplet flows are widely used in aerospace and power engineering. The problems of weakening and suppression of detonation during saturation of a gas or liquid flow with the array of solid particles are considered. The tasks, associated with the formation of particles arrays, dust lifting behind a t...

A coupled computational algorithm for modified Navier–Stokes equations to simulate flows in anisotropic porous media is proposed and described. The difference from the classic SIMPLE algorithm is in the completely implicit relationship between velocity and pressure owing to the implicit terms of the pressure and mass flow gradients in the continuit...

The flow of combustion products containing condensed-phase particles over the recessed vectorable nozzle of a solid-propellant rocket motor was investigated with the use of the Reynolds-averaged Navier–Stokes equations, equations of the k–ε model of turbulence, and the Lagrange approach. The fields of flows of combustion products and the mechanical...

Numerical simulation of gasdynamic processes accompanying the operation of the recessed nozzle of a solid-propellant rocket motor in its linear displacement is carried out. Reynolds-averaged Navier–Stokes equations closed using the equations of a k–ε turbulence model are used for calculations. The calculations are done for different rates of flow o...

A pulse detonation engine is an unsteady propulsive device in which the combustion chamber is periodically filled with a reactive gas mixture, a detonation is initiated, the detonation wave propagates through the chamber, and the combustion products are exhausted. The high pressures and resultant momentum flux out of the chamber generate thrust. Th...

Thrust vectoring technique can deflect the mean flow of an engine jet from the centerline in order to transfer some force to the aimed axis. The secondary injection thrust vector control is particularly attractive for thrust vectoring in large boosters (especially solid propellant rocket) where large side thrust is generated. Injection of a seconda...

The concepts and methods of the visual representation of fluid dynamics computations of vortical flows are studied. Approaches to the visualization of vortical flows based on the use of various definitions of a vortex and various tests for its identification are discussed. Examples of the visual representation of solutions to some fluid dynamics pr...

The formulation and solution of two-dimensional gas-dynamics problems associated with the interaction of shock waves, rarefaction waves, and contact discontinuities in the computational domain of simple configuration are discussed. Results of calculations corresponding to different configurations of a two-dimensional Riemann problem are given, and...

The solution of a number of problems of gas dynamics that are associated with cylindrically and spherically symmetric nonstationary compression of an inviscid gas is considered. Discretization of the Euler equations is carried out with the aid of the method of finite volumes and difference schemes of the WENO type. The results of numerical simulati...

Computational methods are widely used in prediction of complex flowfields associated with off-normal situations in aerospace engineering. Modern graphics processing units (GPU) provide architectures and new programming models that enable to harness their large processing power and to design computational fluid dynamics (CFD) simulations at both hig...

Metal particles are widely used in space engineering to increase specific impulse and to supress acoustic instability of intra-champber processes. A numerical analysis of the internal injection-driven turbulent gas-particle flows is performed to improve the current understanding and modeling capabilities of the complex flow characteristics in the c...

Two-phase systems that involve gas-particle or gas-droplet flows are widely used in aerospace and power engineering. The problems of weakening and suppression of detonation during saturation of a gas or liquid flow with the array of solid particles are considered. The tasks, associated with the formation of particles arrays, dust lifting behind a t...

A numerical simulation of the hydrodynamic effects arising in the process of work of the vectorable thrust nozzle of a solid-propellant rocket engine has been performed. The fields of the flows of combustion products in the channel of a charge, the prenozzle space, and the nozzle unit were calculated for different angles of vectoring of the nozzle....

We consider numerical simulation of shock wave refraction on plane contact discontinuity, separating two gases with different density. Discretization of Euler equations is based on finite volume method and WENO finite difference schemes, implemented on unstructured meshes. Integration over time is performed with the use of the third-order Runge–Kut...

Subject of Research. Numerical simulation results and investigation of shock wave diffraction of differentintensity on the flat right angleare presented. Method. The numerical model is based on the solution of unsteadyEuler equations for inviscid compressible gas. The finite volume method and explicit WENO-type difference scheme of the third-order...

Issues concerning the implementation and practical application of geometric and algebraic multigrid techniques for solving systems of difference equations generated by the finite volume discretization of the Euler and Navier–Stokes equations on unstructured grids are studied. The construction of prolongation and interpolation operators, as well as...

We present the most relevant works on jet engine design that utilize thermodynamic cycle of detonative combustion. Detonation engines of various concepts, pulse detonation, rotational and engine with stationary detonation wave, are reviewed. Main trends in detonation engine development are discussed. The most important works that carried out theore...

We present the most relevant works on jet engine design that utilize thermodynamic cycle of detonative combustion. The efficiency advantages of thermodynamic detonative combustion cycle over Humphrey combustion cycle at constant volume and Brayton combustion cycle at constant pressure were demonstrated. An ideal Ficket-Jacobs detonation cycle, and...

In this article we reviewed the shock wave oscillation that occurs when supersonic flows interact with conic, blunt or flat nose of aircraft, taking into account the aerospike attached to it. The main attention was paid to the problem of numerical modeling of such oscillation, flow regime classification, and cases where aerospike attachment can lea...

The problem of reducing the likelihood of detonation and explosion during saturation of a gas or liquid flow with the cloud of particles is considered. The tasks, associated with the formation of particles clouds, dust lifting behind a travelling shock wave, ignition of particles in high-speed and high-temperature gas flows are adjoined to these pr...

A mathematical model of optical breakdown at the droplets of dielectric liquid exposed to pulsed laser radiation is developed. The following results are obtained by calculation methods: the distribution of pressure, density and temperature in the vapour aureole of the particle; the temperature field around the droplet of liquid. It has been found t...

Aim of the study. This study examines numerical methods for solving the problems in gas dynamics, which are based on an exact or approximate solution to the problem of breakdown of an arbitrary discontinuity (the Riemann problem). Results. Comparative analysis of finite difference schemes for the Euler equations integration is conducted on the basi...

In this article we reviewed the main concepts of detonative combustion. Concepts of slow and fast combustion, of detonation adiabat are introduced. Landmark works on experimental and semi-empirical detonation study are presented. We reviewed Chapman– Jouguet stationary detonation and spin detonation. Various mathematical model of detonation wave ha...

Specific features of simulation of free convective flows of viscous compressible fluids based on the full Navier–Stokes equations are considered. The finite volume discretization of the Navier–Stokes equations in the case of low Mach numbers is discussed. To stabilize the numerical computations, preconditioning, which is based on the use of physica...