Abstract Low‐pressure gas discharge plasmas are known to be strongly affected by the presence of small dust particles. This issue plays a role in investigations particle‐forming plasmas, where dust‐induced instabilities may affect properties synthesized Also, discharges with large amounts microparticles used microgravity experiments, coupled subsystems charged represent particle‐resolved models liquids and solids. In this field, deep understanding dust–plasma interactions is required...

Abstract The anode boundary layer in atmospheric pressure arc discharges is studied numerically on the basis of hydrodynamic (diffusion) equations for plasma components. governing are formulated a unified manner without assumptions thermal equilibrium, ionization equilibrium or quasi-neutrality. For comparison, quasi-neutral model also considered. numerical computations performed an argon at typical values current density layers (500–2000 A cm −2 ). results modelling show that common...

The longitudinal sound speed in two-dimensional Yukawa fluids is estimated using the conventional hydrodynamic expression supplemented by appropriate thermodynamic functions proposed recently Khrapak et al. [Phys. Plasmas 22, 083706 (2015)]. In contrast to existing approaches, such as quasi-localized charge approximation (QLCA) and molecular dynamics simulations, our model provides a relatively simple estimate for over wide range of parameters interest. At strong coupling, results are shown...

Thermodynamics of weakly screened (near the one-component-plasma limit) Yukawa fluids in two and three dimensions is analyzed detail. It shown that thermal component excess internal energy these fluids, when expressed terms properly normalized coupling strength, exhibits scaling pertinent to corresponding limit (the scalings differ considerably between two- three-dimensional situations). This provides us with a simple accurate practical tool estimate thermodynamic properties fluids....

Abstract Cold atmospheric pressure plasma jets (CAPJs) are an emerging technology for the localised treatment of heat sensitive surfaces. Adding humidity to CAPJ’s feed gas yields effective production highly reactive intermediate species, such as hydrogen atoms, oxygen and hydroxyl radicals, among others, which key species biomedical applications. This study focusses on effluent CAPJ kINPen, was operated with argon a admixture 3000 ppm, while curtain used limit diffusion ambient air into...

The effect of ion-neutral collisions on charging micrometer-sized dust grains immersed in a low-pressure argon discharge plasma is studied the basis Vlasov-Bhatnagar-Gross-Krook kinetic equations. equations are solved numerically using method described our previous work [I. L. Semenov et al., Phys. Plasmas 18, 103707 (2011)]. A modified version numerical proposed to reduce required computational time. Numerical calculations carried out for typical parameters used laboratory investigations...

A new approximate expression for the potential distribution around an absorbing particle in isotropic collisionless plasma is proposed. The given by sum of Debye-Hückel with effective screening length and far-field asymptote obtained from solution linearized Poisson equation. In contrast to analogous models, not fixed but depends on distance particle. This allows us obtain a more accurate approximation entire range distances. dependence predicted analysis charge density function. contains...

Screening of a dust grain in weakly ionized plasma is studied for wide range collisional regimes. The problem considered on the basis Vlasov-Bhatnagar-Gross-Krook equations particles. are solved numerically parallel processors by means high-order finite-volume method. computations carried out different pressures background and sizes. values total charge, distributions electric potential, basic macroscopic parameters particles (concentration, temperature, velocity) obtained. For two limiting...

The problem of calculating the ion drag force acting on a dust grain immersed in weakly ionized collisional plasma is studied using an approach based direct numerical solution Vlasov-Bhatnagar-Gross-Krook kinetic equations. A uniform subthermal flow argon past spherical considered. computations are performed for wide range pressures. On basis obtained results, effect ion-neutral collisions analyzed collisionality. In collisionless limit, our results shown to be good agreement with by binary...

The momentum transfer cross-section for ion scattering on charged dust particles is calculated using different models of the interaction potential. results are applied to estimate drag force typical conditions used in experiments with complex (dusty) plasmas. influence two factors ion-dust collision cross section discussed. first related nonlinear screening effects associated strong coupling between ions and particles. second factor plasma absorption by It shown that importance affect both...

The effect of micron-sized particles on a low-pressure capacitively-coupled rf discharge is studied both experimentally and using numerical simulations. In the laboratory experiments, microparticle clouds occupying considerable fraction volume are supported against gravity with help thermophoretic force. spatiotemporally resolved optical emission measurements performed different arrangements microparticles. simulations carried out basis one-dimensional hybrid (fluid-kinetic) model describing...

A simple analytical model of binary alloy anode evaporation in gas–tungsten arc and gas–metal welding is proposed. The comprises the convective diffusive regimes, processes allows one to calculate basic physical properties multicomponent plasma near surface as functions temperature, chemical composition, electron temperature electric current density at surface. Evaporation Al–Mg alloys with different magnesium mass fraction into argon considered on basis proposed model. dependences boiling...

A two-dimensional, axisymmetric model of turbulent reacting flow for a cold atmospheric pressure argon plasma jet has been developed. The is formulated within the framework boundary-layer theory and allows to study transport chemical processes in with low computational effort. generation primary reactive gas species described using local zero-dimensional reaction kinetics model. proposed modelling approach validated against available experimental data. computations are performed operated...

We demonstrate experimentally that the void in capacitively-coupled RF complex plasmas can exist two qualitative different regimes. The "bright" is characterized by bright plasma emission associated with void, whereas "dim" possesses no detectable feature. transition from dim to regime occurs an increase of discharge power and has a discontinuous character. discontinuity manifested kink size dependencies. reproduce (mechanically stabilized due balance ion drag electrostatic forces)...

A unique type of quasi-two-dimensional complex plasma system was observed which consisted monodisperse microspheres and their binary agglomerations (dimers). The particles dimers levitated in a sheath at slightly different heights formed two distinct sublayers. did not crystallize may be characterized as disordered solid. were identified based on characteristic appearance defocused images, i.e., rotating interference fringe patterns. in-plane interplane particle separations exhibit...

The influence of a supersonic projectile on three-dimensional complex plasma is studied. Micron sized particles in low-temperature formed large undisturbed system the new 'Zyflex' chamber during microgravity conditions. A probe particle excited Mach cone with number M $\approx$ 1.5 - 2 and double structure weakly damped cloud. speed sound measured different methods charge estimations are compared to calculations from standard theories. high image resolution enables study cones single level...

A one-dimensional fluid model for ions in weakly ionized plasma is proposed. The differs from the existing ones two aspects. First, a more accurate approximation of collision terms equations suggested. For this purpose, results obtained using Monte Carlo kinetic ion swarm experiments are considered. Second, energy equation taken into account. closed simple velocity distribution function. accuracy examined by comparing with particle-in-cell simulations. In particular, several test problems...

Spiking neural networks (SNNs) are a parallel branch of the development artificial (ANNs) and SNNs obviously significantly different from ANNs. In SNNs, unlike ANNs, information transmitted neuron to is an object that corresponds nerve impulse in brain, other words, spike between neurons through synaptic communication. The functioning this case manifests itself only as generation spikes. Research shows can work with single-bit signals virtually no loss accuracy. promise prospects force such...

This article considers such a problem of spiking neural networks as learning. After all, despite the fact that now there are training methods Hebbian and STDP, still no would provide better performance than second-generation networks. Gradient descent, due to SNN uses differential impulses, cannot be applied training. Therefore, it is necessary develop for supervised machine learning, which challenging task biological realism Another important hardware component. The device must simulate...

We discuss the diagnostics of a complex plasma cloud recorded in experiments performed framework Ekoplasma project. A supersonic extra particle is used as probe dynamics. fine-structured Mach cone behind observed. investigate spatial and temporal development with computer based measurement to determine speed sound cloud. Also time position dependent characteristics velocity field are recorded.

The problem of calculating the ion drag force acting on a charged macroparticle in collisionless flowing plasma is studied by using an approach based direct numerical solution Vlasov kinetic equations for components. A uniform flow past spherical considered. computations are carried out different particle sizes and velocities. On basis obtained results effect size analyzed. It shown that when much less than Debye length plasma, can be calculated with good accuracy means conventional binary...