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Since the publication of the Newman-Penrose (“NP”) equations in 1962 they have been regarded as simply a different version of the Einstein field equations (“EFEs”). This paper reports the fact that symmetry methods can be employed to reduce the complexity of the NP equations, reformulated in terms of the elements of the metric tensor rather than the spin coefficients, and to derive the exact solution in the reference frame of an observer who is in radial free fall through the external vacuum gravitational field of an isolated, non-rotating, spherically symmetric gravitating body. While the domain of the solution is confined to the axis along which the observer falls, it can be directly compared to the Schwarzschild solution and is shown to differ from that solution.Since the publication of the Newman-Penrose (“NP”) equations in 1962 they have been regarded as simply a different version of the Einstein field equations (“EFEs”). This paper reports the fact that symmetry methods can be employed to reduce the complexity of the NP equations, reformulated in terms of the elements of the metric tensor rather than the spin coefficients, and to derive the exact solution in the reference frame of an observer who is in radial free fall through the external vacuum gravitational field of an isolated, non-rotating, spherically symmetric gravitating body. While the domain of the solution is confined to the axis along which the observer falls, it can be directly compared to the Schwarzschild solution and is shown to differ from that solution.

This paper describes the overview of quantum approach for measurements and analysis of data, obtained with the help of acoustic emission, which is considered as a new approach in the field of detection, determination of coordinates and monitoring of sources of acoustic emission associated with discontinuities on the surface, or in the volume of the vessel wall, welded joint and manufactured parts and components. An analysis of the advantages of this approach over the classical approach is given. A block diagram of the quantum system of AE (acoustic emission) – control is presented.This paper describes the overview of quantum approach for measurements and analysis of data, obtained with the help of acoustic emission, which is considered as a new approach in the field of detection, determination of coordinates and monitoring of sources of acoustic emission associated with discontinuities on the surface, or in the volume of the vessel wall, welded joint and manufactured parts and components. An analysis of the advantages of this approach over the classical approach is given. A block diagram of the quantum system of AE (acoustic emission) – control is presented.

The paper deals with homogenization of the generalized Poisson–Nernst–Planck problem stated in the disconnected domain composed of solid and pore phases. The nonlinear cross-diffusion transport equations are coupled with the Stokes flow model. At the interface between two phases, field variables are discontinuous allowing jumps, and nonlinear interface conditions describing electro-chemical reactions are taken into consideration. The first-order asymptotic corrector corresponding to the non-periodic interface data is derived rigorously and justified by residual error estimates within the homogenization procedure.The paper deals with homogenization of the generalized Poisson–Nernst–Planck problem stated in the disconnected domain composed of solid and pore phases. The nonlinear cross-diffusion transport equations are coupled with the Stokes flow model. At the interface between two phases, field variables are discontinuous allowing jumps, and nonlinear interface conditions describing electro-chemical reactions are taken into consideration. The first-order asymptotic corrector corresponding to the non-periodic interface data is derived rigorously and justified by residual error estimates within the homogenization procedure.

Let X be a finite set of m elements. Let On(X) be the set of all n-ary operations on X. On On(X), it is defined operation “+” with (f+g)(x¯)=f(g(x_1),g(x_2),…,g(x_n)), for all f, g ∈ On(X) and x¯=(x1,x2,…,xn) ∈ Xn, so that (On(X), +) is a semigroup. In this paper we give some properties of idempotent elements, regular elements, coregular elements, left zero elements and right identity elements on On(X). Moreover, from this properties, we provide some properties of nontrivial subsemigroups of the semigroup (On(X), +).Let X be a finite set of m elements. Let On(X) be the set of all n-ary operations on X. On On(X), it is defined operation “+” with (f+g)(x¯)=f(g(x_1),g(x_2),…,g(x_n)), for all f, g ∈ On(X) and x¯=(x1,x2,…,xn) ∈ Xn, so that (On(X), +) is a semigroup. In this paper we give some properties of idempotent elements, regular elements, coregular elements, left zero elements and right identity elements on On(X). Moreover, from this properties, we provide some properties of nontrivial subsemigroups of the semigroup (On(X), +).

The basic problems of the previous generations of the mirror traps, like MHD and kinetic stability and longitudinal thermal conductivity, were successfully solved, making it possible to reach temperatures much higher than it was supposed by the sceptics in early 2000-s. This paper sums up the experiments on magnetic mirrors in the Budker INP and their contribution to the next-step linear machine efforts. Current program of the linear machines for fusion exploits both experimentally verified and recently proposed methods of the longitudinal particle and energy loss suppression. Linear machine with improved enough longitudinal confinement is suitable for fusion with advanced fuels. Ways of the suppression are verified at GDT (gas-dynamic), GOL-NB (multiple-mirror), SMOLA (helical) and CAT (diamagnetic) devices. Next-generation GDMT project includes all the discussed ideas.The basic problems of the previous generations of the mirror traps, like MHD and kinetic stability and longitudinal thermal conductivity, were successfully solved, making it possible to reach temperatures much higher than it was supposed by the sceptics in early 2000-s. This paper sums up the experiments on magnetic mirrors in the Budker INP and their contribution to the next-step linear machine efforts. Current program of the linear machines for fusion exploits both experimentally verified and recently proposed methods of the longitudinal particle and energy loss suppression. Linear machine with improved enough longitudinal confinement is suitable for fusion with advanced fuels. Ways of the suppression are verified at GDT (gas-dynamic), GOL-NB (multiple-mirror), SMOLA (helical) and CAT (diamagnetic) devices. Next-generation GDMT project includes all the discussed ideas.

As a part of the Argonne Strategic Partnership Project (SPP) 85E77, collaboration between Argonne National Laboratory (ANL) and Shanghai Institute of Applied Physics (SINAP), has produced designs for a precision compact flexure bending mechanism to provide elliptically shaped 90-mm and 160-mm long hard x-ray mirrors. The design utilizes Argonne’s laminar nanopositioning flexure technique. The flexure mirror bending mechanism will be incorporated into the beamline upgrade project at the Shanghai Synchrotron Radiation Facility (SSRF). Additionally, an Argonne Laboratory-Directed Research and Development (LDRD) project at the Advanced Photon Source (APS) has adopted a modified optomechanical design of the precision compact mirror benders for 300-mm-long hard x-ray mirrors with integrated profile monitoring and feedback, which are described in this paper. The mirror benders are designed with configurations for open-loop or closed-loop controls. Capacitive sensors can be applied to the mirror benders to ensure positioning reproducibility. Design specifications as well as finite element analyses results of the compact mirror benders for hard x-ray mirrors with trapezoid and rectangular shapes are discussed in this paper.

Spherical Tokamak (ST) path to Fusion has been proposed [1] and experiments on STs demonstrated feasibility of this approach. Advances in High Temperature Superconductor technology [2] allows significant increase in the toroidal field (TF) which was found to improve confinement in STs. The combination of the high normalised plasma pressure, β, which has been achieved in STs [3], and high TF that can be produced by HTS TF magnets, opens a path to lower-volume fusion reactors, in accordance with the fusion power scaling proportional to β2Bt4V. Modular approach then becomes an alternative to high power, GW-scale Fusion reactors [4,5]. Feasibility of low-power compact ST reactor module and physics and engineering challenges of the accelerated, ST path to Fusion Power are discussed in this paper, on example of the first our prototype on this route, high-field compact spherical tokamak ST40.Spherical Tokamak (ST) path to Fusion has been proposed [1] and experiments on STs demonstrated feasibility of this approach. Advances in High Temperature Superconductor technology [2] allows significant increase in the toroidal field (TF) which was found to improve confinement in STs. The combination of the high normalised plasma pressure, β, which has been achieved in STs [3], and high TF that can be produced by HTS TF magnets, opens a path to lower-volume fusion reactors, in accordance with the fusion power scaling proportional to β2Bt4V. Modular approach then becomes an alternative to high power, GW-scale Fusion reactors [4,5]. Feasibility of low-power compact ST reactor module and physics and engineering challenges of the accelerated, ST path to Fusion Power are discussed in this paper, on example of the first our prototype on this route, high-field compact spherical tokamak ST40.

The most recent Nijmegen extended-soft-core ESC16 model for the baryon-baryon (BB) interactions of the SU(3) flavor-octet of baryons (N, Λ, Σ, and Ξ) is presented. The ESC model ESC16, as well as its predecessors ESC08 and ESC04, describe the nucleon-nucleon (NN), hyperon-nucleon (YN), and hyperon-hyperon (YY) interactions in a unified way using broken SU(3) symmetry. In this paper we outline the differences between ESC16 and ESC08c.The parameters of the ESC models are established in a simultaneous fit to the NN and YN data, taking into account information about ΛΛ, ΞN, and Λ-hypernuclei in the form of constraints. In particular, the experimental indications for ΛΛ-attraction, Ξ-nuclear and Σ-nuclear well-depth were taken into account as much as possible. About 25 physical coupling parameters and 8 cut-off and diffractive masses, were searched. The obtained OBE-couplings and the F/(F+D) ratios can be well understood in the context of the quark-antiquark pair creation (QPC) mechanism.The fit of the ESC-models to the NN- and YN- scattering data with a single set of parameters has achieved excellent results for the NN and YN data, and for the YY data in accordance with the experimental indications for ΛΛ. In the case of the most recent ESC model, called ESC16, the achievements are: (i) For the selected 4313 pp and np scattering data with energies 0 ≤ Tlab ≤ 350 MeV, the model reaches a fit having χ2/Ndata = 1.10. (ii) The deuteron binding energy and all of the NN scattering lengths are fitted very nicely. (iii) The YN data are described very well with χ2 /Ndata = 1.11, giving at the same time good descriptions of the Λ, Σ, and Ξ nuclear well-depths. (iv) The model has no bound states for S = −1,−2,−3,−4. (v) The nuclear saturation, and well-depths UΣ, UΞ require important contributions from three-body forces.The most recent Nijmegen extended-soft-core ESC16 model for the baryon-baryon (BB) interactions of the SU(3) flavor-octet of baryons (N, Λ, Σ, and Ξ) is presented. The ESC model ESC16, as well as its predecessors ESC08 and ESC04, describe the nucleon-nucleon (NN), hyperon-nucleon (YN), and hyperon-hyperon (YY) interactions in a unified way using broken SU(3) symmetry. In this paper we outline the differences between ESC16 and ESC08c.The parameters of the ESC models are established in a simultaneous fit to the NN and YN data, taking into account information about ΛΛ, ΞN, and Λ-hypernuclei in the form of constraints. In particular, the experimental indications for ΛΛ-attraction, Ξ-nuclear and Σ-nuclear well-depth were taken into account as much as possible. About 25 physical coupling parameters and 8 cut-off and diffractive masses, were searched. The obtained OBE-couplings and the F/(F+D) ratios can be well understood in the context of the quark-antiquark pair creation (QPC) mechanism.The fit of the ESC-mod...

The extraction of negative ions request conditions such as electrons are magnetized, so that a collisionless model is clearly overoptimistic, and collisions must be included to model electron co-extraction (an undesired effect). Collision dependence from speed is fully treated in this paper, addressing also the difficult case of Coulomb collisions. The kinetic effects are important in the sheath and presheath region, giving integral equations for electron density, current and collision variation along extraction axis z. With a careful description of the closed orbit variables and of the recirculation effect, integral kernels are reduced to expression suitable for computation. Numerical results for the plasma conductivity and average emission angle in Coulomb collision dominated regime are given and compared with similar results of constant collision frequency models.The extraction of negative ions request conditions such as electrons are magnetized, so that a collisionless model is clearly overoptimistic, and collisions must be included to model electron co-extraction (an undesired effect). Collision dependence from speed is fully treated in this paper, addressing also the difficult case of Coulomb collisions. The kinetic effects are important in the sheath and presheath region, giving integral equations for electron density, current and collision variation along extraction axis z. With a careful description of the closed orbit variables and of the recirculation effect, integral kernels are reduced to expression suitable for computation. Numerical results for the plasma conductivity and average emission angle in Coulomb collision dominated regime are given and compared with similar results of constant collision frequency models.

As an important and complex issue in aero acoustic field, a lot of explorations have been devoted to the wind-induced noise. However, there is still lack of intensive investigations for aerodynamic noise in high-voltage transmission. The overhead transmission line system leads to serious occupational noise exposure in high wind-speed environment, and the noise can even injure the electricians in charge of insulator. By using computational fluid dynamics (CFD) which combined with computational aero acoustics (CAA), this paper predicts the noise generated by insulator of high voltage electricity transmission line which explores in wind environment. The simulation results indicate that the wind velocity, the assembly angle of the insulator and its ribs’ distribution are the main contributory factors for the aerodynamic noise. Specifically, when wind velocity is greater than 15m/s, the alteration of noise is not sensitive to the wind velocity; furthermore, when the assembly angle increases from 0°to 60°, the noise decreases gradually, however, if the angle is happening to be 75°or 90°, it would be even greater than that at 0°. In order to inhibit the aerodynamic noise, it is necessary to control the flow blowing across the boundary of the insulator. Consequently, the result indicates that if the outermost rib is shorter than the second one, the noise reduced evidently. This information expects to provide useful help for the extremely suppression of aerodynamic noise, and also supply practical reference material for the design and application of overhead transmission line system.As an important and complex issue in aero acoustic field, a lot of explorations have been devoted to the wind-induced noise. However, there is still lack of intensive investigations for aerodynamic noise in high-voltage transmission. The overhead transmission line system leads to serious occupational noise exposure in high wind-speed environment, and the noise can even injure the electricians in charge of insulator. By using computational fluid dynamics (CFD) which combined with computational aero acoustics (CAA), this paper predicts the noise generated by insulator of high voltage electricity transmission line which explores in wind environment. The simulation results indicate that the wind velocity, the assembly angle of the insulator and its ribs’ distribution are the main contributory factors for the aerodynamic noise. Specifically, when wind velocity is greater than 15m/s, the alteration of noise is not sensitive to the wind velocity; furthermore, when the assembly angle increases from 0°to 60°, the ...

This paper provides a method for determining the rotational temperature of a molecular ensemble subject to a pump pulse. To implement it, we measure the rotational energy by using the molecular wave function, take the rotational energy as the thermal energy, and extract the rotational temperature. This method is able to follow the dynamics of rotational temperature, calculate the temperature increase during the interaction with the pump pulse, and predict the cause. An accurate rotational temperature ensures better information about molecular ensembles.This paper provides a method for determining the rotational temperature of a molecular ensemble subject to a pump pulse. To implement it, we measure the rotational energy by using the molecular wave function, take the rotational energy as the thermal energy, and extract the rotational temperature. This method is able to follow the dynamics of rotational temperature, calculate the temperature increase during the interaction with the pump pulse, and predict the cause. An accurate rotational temperature ensures better information about molecular ensembles.

In this paper, we examine the geodesic equation around a global monopole within an asymptotically flat black hole using Eddington-inspired Born-Infeld (EiBI) theory of gravity. In particular, we study massive particle motion around the black hole. We find that the effective potential and radial force for this massive particle depend on the coupling constant of EiBI gravity.In this paper, we examine the geodesic equation around a global monopole within an asymptotically flat black hole using Eddington-inspired Born-Infeld (EiBI) theory of gravity. In particular, we study massive particle motion around the black hole. We find that the effective potential and radial force for this massive particle depend on the coupling constant of EiBI gravity.

In the paper a description of heat transfer in a one-dimensional two-layered metal film is considered. The fuzzy coupled lattice Boltzmann equations for electrons and phonons supplemented by appropriate boundary and initial conditions are applied to analyse the thermal process in a thin metal film. The model with fuzzy values of relaxation times and boundary-initial conditions for gold and titanium is proposed. The problem considered is solved by the fuzzy lattice Boltzmann method using α-cuts and the rules of directed interval arithmetic. The application of α-cuts allows one to avoid complicated arithmetical operations in the fuzzy numbers set. In the final part of the paper an example for a numerical solution is presented.In the paper a description of heat transfer in a one-dimensional two-layered metal film is considered. The fuzzy coupled lattice Boltzmann equations for electrons and phonons supplemented by appropriate boundary and initial conditions are applied to analyse the thermal process in a thin metal film. The model with fuzzy values of relaxation times and boundary-initial conditions for gold and titanium is proposed. The problem considered is solved by the fuzzy lattice Boltzmann method using α-cuts and the rules of directed interval arithmetic. The application of α-cuts allows one to avoid complicated arithmetical operations in the fuzzy numbers set. In the final part of the paper an example for a numerical solution is presented.

Penetration conditions of electromagnetic and electrostatic waves propagating in electron cyclotron resonance (ECR) ion source (ECRIS) plasma in Osaka Univ. have been examined in detail, and its relationship with the production of multicharged ions have been investigated experimentally. It has been clarified that there exists efficient configurations of ECR zones for producing multicharged ion beams, and it has been suggested that new resonances, i.e. upper hybrid resonances, must have occurred. We have been conducting new advanced experiments inducing actively these additional effects to enhance multicharged ion beams by launching extra-ordinary (x) mode waves. We have been trying to apply 4-6GHz x-mode microwaves to the 2.45GHz ECRIS, and in this paper we will describe the preliminary experimental results.Penetration conditions of electromagnetic and electrostatic waves propagating in electron cyclotron resonance (ECR) ion source (ECRIS) plasma in Osaka Univ. have been examined in detail, and its relationship with the production of multicharged ions have been investigated experimentally. It has been clarified that there exists efficient configurations of ECR zones for producing multicharged ion beams, and it has been suggested that new resonances, i.e. upper hybrid resonances, must have occurred. We have been conducting new advanced experiments inducing actively these additional effects to enhance multicharged ion beams by launching extra-ordinary (x) mode waves. We have been trying to apply 4-6GHz x-mode microwaves to the 2.45GHz ECRIS, and in this paper we will describe the preliminary experimental results.

Effect of polarization force on dust kinetic Alfven waves (DKAWs) has been studied in this paper. We incorporated the effect of polarization in fluid model equations and derived the expression for Sagdeev pseudopotential. From the numerical analysis, it is seen that DKAWs are significantly affected by the variation of polarization force, plasma beta and Mach number. This study may be useful in understanding the formation of coherent nonlinear structures and diagnostics of dusts in laboratory as well as in space/astrophysical plasma environments.Effect of polarization force on dust kinetic Alfven waves (DKAWs) has been studied in this paper. We incorporated the effect of polarization in fluid model equations and derived the expression for Sagdeev pseudopotential. From the numerical analysis, it is seen that DKAWs are significantly affected by the variation of polarization force, plasma beta and Mach number. This study may be useful in understanding the formation of coherent nonlinear structures and diagnostics of dusts in laboratory as well as in space/astrophysical plasma environments.

In this paper is presented a wind turbine model operating in the maximum power zone and an H∞ controller is synthesized for the system. The developed turbine model consists of: a model of the wind speed, mechanical and electrical model of the generator and a model of the tower oscillations. The controller adjusts the pitch angle of the blades so that the rotor angular velocity stays close to its nominal value and as a result the tower oscillations are decreased. Finally, the operation of the closed-loop system model is validated by simulationsIn this paper is presented a wind turbine model operating in the maximum power zone and an H∞ controller is synthesized for the system. The developed turbine model consists of: a model of the wind speed, mechanical and electrical model of the generator and a model of the tower oscillations. The controller adjusts the pitch angle of the blades so that the rotor angular velocity stays close to its nominal value and as a result the tower oscillations are decreased. Finally, the operation of the closed-loop system model is validated by simulations

The paper presents the results of numerical simulation of the flow around a hypersonic inlet forebody to the entrance to the channel as well as the flow in a single boundary layer bleed channel. Simulation of the flow around the hypersonic inlet forebody has been carried out at Mach numbers M = 3, 4 6 and angles of attack of 4° and 6° using numerical solution of the Reynolds- averaged Navier-Stokes equations. Distributions of static pressure along the plane of symmetry and in the transverse direction are presented in the paper. Comparison of the numerical simulation results with experimental data has shown their satisfactory agreement. The parameters behind the bow shock wave obtained at the simulation of the flow around the inlet forebody have been used to specify the initial conditions for simulation of the flow through a boundary layer bleed hole.

This paper contributes to the proceedings of the Latin-American School of Physics (ELAF-2017) on Quantum Correlations, and is a brief review of quantum entanglement and nonlocality. In such a brief review, only some topics can be covered. The emphasis is on those topics relevant that may be relevant to detecting multi-particle quantum correlations arising in atomic and Bose-Einstein condensate (BEC) experiments. The paper is divided into five sections. In the first section, the historical papers of Einstein-Podolsky-Rosen (EPR), Bell, Schrodinger and Greenberger-Zeilinger-Horne (GHZ) are described in a tutorial fashion. This is followed by an introduction to entanglement and density operators. A discussion of the classes of nonlocality is given in the third section, including the modern interpretation of the correlations of the EPR paradox experiments, known as EPR steering correlations. The fourth section covers the detection and generation of so-called continuous variable entanglement and EPR steering. Various known criteria are derived with the details of the proofs given for tutorial purposes. The final section focuses on the criteria and methods that have been useful to detect quantum correlation in BEC or atomic systems. Recent results relating spin squeezing with quantum correlations, including entanglement and EPR steering, are summarised.

This paper investigates the outdoor performance of a new kind of hybrid concentrator photovoltaic module. The concept which we name, EyeCon, uses an array of Fresnel lenses to concentrate direct irradiance onto III-V four-junction solar cells while a large-area silicon cell absorbs diffuse sunlight and also acts as a heat distributing substrate. The preliminary results show that under a high ratio of direct to global irradiance (> 0.9) the concept is capable to convert up to 36.8 % of the global solar resource rather than just the direct beam. Moreover at a low ratio of direct to global irradiance (0.57) the hybrid module generates 30 % additional power with respect to the array of concentrator four-junction solar cells alone. The Eyecon module is applicable to all regions of the world and allows reaching the highest energy yield per module area of any PV technology.This paper investigates the outdoor performance of a new kind of hybrid concentrator photovoltaic module. The concept which we name, EyeCon, uses an array of Fresnel lenses to concentrate direct irradiance onto III-V four-junction solar cells while a large-area silicon cell absorbs diffuse sunlight and also acts as a heat distributing substrate. The preliminary results show that under a high ratio of direct to global irradiance (> 0.9) the concept is capable to convert up to 36.8 % of the global solar resource rather than just the direct beam. Moreover at a low ratio of direct to global irradiance (0.57) the hybrid module generates 30 % additional power with respect to the array of concentrator four-junction solar cells alone. The Eyecon module is applicable to all regions of the world and allows reaching the highest energy yield per module area of any PV technology.

The generator is one of the tools that used in power system circuit. The working system of electrical generators is converted the mechanical energy from an external source into electrical energy as output. The generator works by exploiting the electric flux generated by a magnetic field that passes through the rotation of the coil on the generator engine. Both of these are things that affect the efficiency level of the generator. If the efficiency of a generator is higher so the electrical energy generated is also greater. In this paper will be analyzed theoretically mathematically to improve the efficiency of the alternating current generator. The analytical review will be performed on magnetic field strength and coil rotation speed. With the increase of these two factors is expected to increase generator efficiency is also increasing so that the electrical energy which is the output of the generator system is also higher.The generator is one of the tools that used in power system circuit. The working system of electrical generators is converted the mechanical energy from an external source into electrical energy as output. The generator works by exploiting the electric flux generated by a magnetic field that passes through the rotation of the coil on the generator engine. Both of these are things that affect the efficiency level of the generator. If the efficiency of a generator is higher so the electrical energy generated is also greater. In this paper will be analyzed theoretically mathematically to improve the efficiency of the alternating current generator. The analytical review will be performed on magnetic field strength and coil rotation speed. With the increase of these two factors is expected to increase generator efficiency is also increasing so that the electrical energy which is the output of the generator system is also higher.

This paper studies on the performance of semiconductor optical amplifiers and microfiber Mach-Zehnder interferometer in the loop mirror of multi-wavelength Brillouin fibre laser configuration. The microfiber Mach-Zehnder interferometer is designed by the using the Optisystem and OptiBPM software. This project has shown that the proposed configuration with semiconductor optical amplifiers and Mach-Zehnder interferometer in the loop mirror has the ability to generate multiple signals. Input BP power of 4dBm has been identified as optimum input power for this configuration since it resulted higher number of output signals generation compared to other input BP power which is from -6dBm, -5dBm to 8dBm The configuration also has the capability to generate up to 19 dominant overall number of output signals at injected SOA current of 0.8A, whereas the minimum SOA current of 0.5A is only required to initiate first signal at input BP power - 6dBm. In conclusion, this paper has successfully demonstrates that of semiconductor optical amplifiers and microfiber Mach-Zehnder interferometer in loop mirror multi-wavelength Brillouin fibre laser configuration can effectively act to generated multiple signals. This multi-wavelength Brillouin fibre laser configuration can be utilized in many applications, especially in optical sensing and for optical communication, since this two field need large scale of number of signals in order to accommodate better results.

Steady-state operation of a fusion neutron source (FNS) requires plasma heating and current drive by means of additional power delivered by neutral beams. Six neutral beam injectors (NBI) will provide DEMO-FNS machine with additional heating power up to 30 MW, with neutral particle energy 500 keV. NBI systems developed for ITER can serve as the prototype for DEMO-FNS, as both systems have similar ion source current, with accelerated beam power in ITER NBI (1 MeV) being twice as large as in DEMO-FNS. The paper describes the NBI system with account of its integration to DEMO-FNS tokamak complex.Steady-state operation of a fusion neutron source (FNS) requires plasma heating and current drive by means of additional power delivered by neutral beams. Six neutral beam injectors (NBI) will provide DEMO-FNS machine with additional heating power up to 30 MW, with neutral particle energy 500 keV. NBI systems developed for ITER can serve as the prototype for DEMO-FNS, as both systems have similar ion source current, with accelerated beam power in ITER NBI (1 MeV) being twice as large as in DEMO-FNS. The paper describes the NBI system with account of its integration to DEMO-FNS tokamak complex.

The aim of the paper is to analyze the synchronization phenomenon of a rotating structure composed of three beams attached to a rigid hub. It is assumed in the calculations that one beam is 10% thicker comparing to the remaining ones. Furthermore, two possible variants of excitation are considered: (a) torque given by harmonic function or (b) torque produced by a chaotic oscillator. Next, the equations have been solved numerically and the resonance curves and time series have been analyzed in terms of synchronized motion of the hub and blades of the rotor. The influence of hub’s mass moment of inertia have been checked as well. For the system with chaotic Duffing oscillator Poincare maps have been obtained.The aim of the paper is to analyze the synchronization phenomenon of a rotating structure composed of three beams attached to a rigid hub. It is assumed in the calculations that one beam is 10% thicker comparing to the remaining ones. Furthermore, two possible variants of excitation are considered: (a) torque given by harmonic function or (b) torque produced by a chaotic oscillator. Next, the equations have been solved numerically and the resonance curves and time series have been analyzed in terms of synchronized motion of the hub and blades of the rotor. The influence of hub’s mass moment of inertia have been checked as well. For the system with chaotic Duffing oscillator Poincare maps have been obtained.

In this paper, we deal with the oblique electromagnetic electron cyclotron (EMEC) waves in the Uranus magnetosphere. The expression of the dispersion relation is plotted by using the method of the feature solution. After the kinetic method, the growth rate and the actual frequency of the EMEC wave are studied theoretically in the Uranian system. NASA, Voyager 2, the observed results of the space detectors show that the spin axes of the planets are abnormally oriented and that there are more particles in the high energy tail of the Uranian magnetospheric plasma. Therefore, this paper uses the Kappa distribution instead of the usual Maxwell distribution. The study extends to the tilt propagation of EMEC waves, which has a change in temperature anisotropy and propagation angle with respect to the direction of the magnetic field. These parameters were found to support the growth rate of EMEC waves. However, the response of the actual frequency of these waves is not the same as the rate of growth in all cases. These results apply to the detailed comparison of planetary studies of the space plasma environment and the magnetosphere system.

The Rim-driven Thruster (RDT) is a new type of marine electric thruster proposed in recent years. In this paper, the author proposed a new type of permanent magnet synchronous rim thrust motor (RTM). The motor uses a Halbach array permanent magnet rotor, which can improve the torque density of the propulsion motor by utilizing the unilateral magnetic field of the Halbach array. In this paper, the electromagnetic properties of the motor were measured and compared with that of the ordinary magnetic pole motor through numerical analysis. The results show that at the same power, the new motor can significantly reduce the thickness of the rotor’s permanent magnet and yoke core, and has obvious advantages in power density, moment of inertia, dynamic performance, and cost.

The paper deals with the minimum compliance problem of 2D structures made of a non-homogeneous elastic material. In the first part of the paper a comparison between solutions of Free Material Design (FMD), Cubic Material Design (CMD) and Isotropic Material Design (IMD) is shown for a simply supported plate in a shape of a deep beam, subjected to a concentrated in-plane force at its upper face. The isoperimetric condition fixes the value of the cost of the design expressed as the integral of the trace of the Hooke tensor. In the second part of the paper the material design approaches are extended to rhombic system in 2D. For the rhombic system the material properties of the structures are set, the design variables being the trajectories of anisotropy directions which in 2D are described by one parameter. In the Orthotropic Orientation Design (OOD) no isoperimetric condition is used.

This paper deals with the numerical investigation of ellipticity of the boundary value problem for isothermal finite strain elasto-plasticity. Ellipticity can be lost when softening occurs. A discontinuity surface then appears in the considered material body and this is associated with the ill-posedness of the boundary value problem. In the paper the condition for ellipticity loss is derived using the deformation gradient and the first Piola-Kirchhoff stress tensor. Next, the obtained condition is implemented and numerically tested within symbolic-numerical tools AceGen and AceFEM using the benchmark of an elongated rectangular plate with imperfection in plane stress and plane strain conditions.

This paper presents the experimental results of the Cleanergy's C11S solar engine-generator tested in the KTH solar simulator. The paper focuses on the analysis of the thermal performance of the ca ...

A new type of power plant. i.e, Electric Power Confined Piston Engine, is invented by combining the free piston engine and the crank connecting rod mechanism of the traditional internal combustion engine. Directly using the reciprocating movement of the piston, this new engine converts the heat energy produced by fuel to electrical energy and output it. The paper expounds the working mechanism of ECPE and establishes the kinematics and dynamics equations. Furthermore, by using the analytic method, the ECPE electromagnetic force is solved at load cases. Finally, in the simulation environment of MARLAB, the universal characteristic curve is obtained in the condition of rotational speed n between 1000 r/min and 2400 r/min, throttle opening α between 30% and 100%.A new type of power plant. i.e, Electric Power Confined Piston Engine, is invented by combining the free piston engine and the crank connecting rod mechanism of the traditional internal combustion engine. Directly using the reciprocating movement of the piston, this new engine converts the heat energy produced by fuel to electrical energy and output it. The paper expounds the working mechanism of ECPE and establishes the kinematics and dynamics equations. Furthermore, by using the analytic method, the ECPE electromagnetic force is solved at load cases. Finally, in the simulation environment of MARLAB, the universal characteristic curve is obtained in the condition of rotational speed n between 1000 r/min and 2400 r/min, throttle opening α between 30% and 100%.

The paper describes new light-gas guns for the high-velocity throwing of different projectiles: an upgraded two-stage light-gas powder gun and single-, two- and three-stage compressed light-gas guns. The paper also provides the schemes, pictures and characteristics of light-gas guns.

Granular materials are widespread in nature and in manufacturing. Their particulate nature gives a compressive strength of a similar order of magnitude as many continuous solids, a vanishingly small tensile strength and variable shear strength, highly dependent on the loading conditions. Previous studies have shown the effect of composition, morphology and particle size, however, compared to metals and polymers, granular materials are not so well understood. This paper will present some recent results for granular materials, placing these within the wider context. Two areas will be dealt with (i) the effect of the skeletal strength of the material and (ii) the displacements associated with ballistic impact. One clear observation is the similarity of behavior of quartz-sands in compression across a range of particle size. However, the precise pathway of compression is strongly dependent on the initial conditions e.g. density and connectivity within the granular bed, as emphasized by some data for quasi-static compression of sand. To fully embrace the range of behaviours seen requires the development of a suitable parameter to describe the material, the paper concludes with a discussion of one of those approaches.

In this paper we present a concept of quantum entanglement in time in a context of entangled consistent histories. These considerations are supported by presentation of necessary tools closely related to those acting on a space of spatial multipartite quantum states. We show that in similarity to monogamy of quantum entanglement in space, quantum entanglement in time is also endowed with this property for a particular history. Basing on these observations, we discuss further bounding of temporal correlations and derive analytically the Tsirelson bound implied by entangled histories for the Leggett-Garg inequalities., Comment: 10 pages, 2 figures. An extended version of a conference paper. To appear in Quantum Retrocausation III (AIP Conference Proceedings edited by Daniel P. Sheehan)

The results of an experimental study of the controlled pulsations development in the spanwise modulated boundary layer of a swept wing are presented in the paper. The experiments were conducted at Mach 2 and unit Reynolds number Re1 = 6×106 m−1. The square stickers were applied to induce the spanwise modulation of mean flow in the boundary layer. It was obtained, that the presence of roughness leads to a decrease of the disturbance source efficiency at the subharmonic and fundamental frequency, and the oblique breakdown mechanism begins to appear at smaller values of the longitudinal coordinate × as compared with the case of a smooth wing.The results of an experimental study of the controlled pulsations development in the spanwise modulated boundary layer of a swept wing are presented in the paper. The experiments were conducted at Mach 2 and unit Reynolds number Re1 = 6×106 m−1. The square stickers were applied to induce the spanwise modulation of mean flow in the boundary layer. It was obtained, that the presence of roughness leads to a decrease of the disturbance source efficiency at the subharmonic and fundamental frequency, and the oblique breakdown mechanism begins to appear at smaller values of the longitudinal coordinate × as compared with the case of a smooth wing.

This paper brings together the most important aspects of nuclear structure and reaction dynamics that may have an influence on stability of superheavy nuclei. These aspects form the basis of current experimental research on heaviest elements to investigate their basic properties. The shell model is used to estimate microscopically the alpha formation amplitude from single quasiparticle states under the influence of the pairing interaction. Half-life calculations for fission are performed in a dynamical approach defined by the shape and the high of fission barrier, the fissility and nuclear deformations. Reaction energies QS F are estimated within the liquid drop model. We predicted with the most probable total half-lives for many unknown nuclides at which there are no experimental data. The rms values for experimental and theoretical half-lives are evaluated and discussed. The comparison of theoretical calculations with experimental data allows us to draw conclusions on the role of the nuclear structure and shell effects in low-energy decay processes.This paper brings together the most important aspects of nuclear structure and reaction dynamics that may have an influence on stability of superheavy nuclei. These aspects form the basis of current experimental research on heaviest elements to investigate their basic properties. The shell model is used to estimate microscopically the alpha formation amplitude from single quasiparticle states under the influence of the pairing interaction. Half-life calculations for fission are performed in a dynamical approach defined by the shape and the high of fission barrier, the fissility and nuclear deformations. Reaction energies QS F are estimated within the liquid drop model. We predicted with the most probable total half-lives for many unknown nuclides at which there are no experimental data. The rms values for experimental and theoretical half-lives are evaluated and discussed. The comparison of theoretical calculations with experimental data allows us to draw conclusions on the role of the nuclear structure a...

I summarize in this paper our previous works on the spin polaron theory as a mechanism for high temperature superconductivity in the finite temperature (Matsubara) Green’s function method. In this formulation, some bulk thermodynamic properties of high-Tc materials like entropy and specific heat are treated. The hole spectral function is likewise derived. Single-particle tunneling current is calculated for normal metal-superconductor and superconductor-superconductor junctions. With an effective Hamiltonian derived from this theory, the Josephson tunneling current between two high temperature superconductors is obtained. Current problems like mobility of holes, calculation of energy gap function, the triplet pairing mechanism, among others, are also discussed in this paper, all using the spin polaron formulation.

Explosive dispersal of particles is a complex multiphase phenomenon that has yet to be fully understood. As the particle cloud disperses at high speed, it experiences multiphase instabilities related to Richtmyer-Meshkov (RM) and Rayleigh-Taylor (RT) instabilities when interacting with the blast-wave structure. This paper reports the results of a numerical experiment where the effect of bimodal perturbations in the initial particle volume fraction is studied. Results indicate that a signature of the initial perturbation profile remains in the particle cloud throughout the observed time, and that adding a bimodal perturbation increases the width of the cloud when compared to a uniform volume fraction distribution.Explosive dispersal of particles is a complex multiphase phenomenon that has yet to be fully understood. As the particle cloud disperses at high speed, it experiences multiphase instabilities related to Richtmyer-Meshkov (RM) and Rayleigh-Taylor (RT) instabilities when interacting with the blast-wave structure. This paper reports the results of a numerical experiment where the effect of bimodal perturbations in the initial particle volume fraction is studied. Results indicate that a signature of the initial perturbation profile remains in the particle cloud throughout the observed time, and that adding a bimodal perturbation increases the width of the cloud when compared to a uniform volume fraction distribution.

The measurement of geomagnetic field conducted by underwater robot is widely used during cruise, however, it is often influenced by the strong electromagnetic interference of the other large-scale electronic equipment on the robot itself. The leakage magnetic field of high-power brushless DC motor (BLDCM) has been identified as one of the main interference source. To obtain accurate geomagnetic data, it is necessary to analyze the magnetic field characteristics of the leakage field of BLDCM. In this paper, we build a two-dimensional BLDCM model. In addition, we present the rotor’s leakage magnetic field when the BLDCM is static, dynamic leakage magnetic field of the stator and rotor when BLDCM is working and the near-field characteristic of BLDCM’s leakage magnetic field. Finally, this paper studies the relationship between the frequency of the magnetic field change and the speed of the BLDCM, which can be used to eliminate the AC interference magnetic field. Therefore the measuring accuracy of the geomag...

The paper describes an advanced gyro-based measuring system comprising a CGV-4K central vertical gyro and a G-3M gyrocompass. The advanced system provides additional functions that help measure unsprung mass rotation angles about a vertical axis, rolling angles, trim angles and movements of the unsprung masses of the front (ap and al) and rear b axes when a car wheel hits a single obstruction. The paper also describes the operation of the system, which measures movements of unsprung masses about the body of a car when it hits a single obstruction. The paper presents the dependency diagrams ap = f(t) and al = f(t) for front and rear wheels respectively, as well as b = f(t) for a rear left wheel, which were determined experimentally. Test results for a car equipped with an advanced gyro-based measuring system moving around a circle can form a basis for developing a mathematical model of the process.

One of the most important goals of experimental gas dynamics is to study formation and evolution of fluctuations generated by flow over some obstacles. Such fluctuations are mostly non-stationary. To analyze such experimental data time-frequency techniques are required such as Hilbert-Huang transform. In this paper some results of application of this technique for data analysis are presented. Specific features, advantages and disadvantages of transform are mentioned. Time series analyzed were obtained in experiments on fluctuations measurements behind a circular cylinder in two different wind tunnels at different speeds but close Reynolds number ranges. Amplitudes of fluctuations behind a cylinder were found to have some specific behavior in each case.One of the most important goals of experimental gas dynamics is to study formation and evolution of fluctuations generated by flow over some obstacles. Such fluctuations are mostly non-stationary. To analyze such experimental data time-frequency techniques are required such as Hilbert-Huang transform. In this paper some results of application of this technique for data analysis are presented. Specific features, advantages and disadvantages of transform are mentioned. Time series analyzed were obtained in experiments on fluctuations measurements behind a circular cylinder in two different wind tunnels at different speeds but close Reynolds number ranges. Amplitudes of fluctuations behind a cylinder were found to have some specific behavior in each case.

Customized flexure mechanisms and precision thermal expansion compensation are needed for the development of nanopositioning stages for hard x-ray nanofocusing and coherence preservation optics at the APS. Recent progress of such stage development is summarized in this paper, which includes: stages designed for alignment apparatus for K-B mirrors with 20 - 50 nm focal spot; alignment apparatus for six Fresnel zone plates stacking with 20 nm focal spot; stages for switchable multiple nanofocusing system; UHV hard x-ray monochromators for coherence related applications; and four-crystal hard x-ray split-and-delay line with coherence preservation. Preliminary test results for mechanical performance of these nanopositioning stages are also discussed in this paper.

Alfvénicity is a feature characterizing solar wind fluctuations and is defined by a high correlation between velocity and magnetic field components and in ideal conditions by equipartition between kinetic and magnetic energies. It is a feature characterizing especially the fast wind while slow wind shows usually lower correlation between velocity and magnetic field components. However this is not always the case. Under certain conditions a high degree of Alfvénicity can be found also within slow wind. In the present paper, we show the existence of two kinds of slow solar wind with similar velocities but which display different characteristics. The different degree of Alfvénicity is a feature discrimanating the two types of slow wind. This feature is always linked to a low magnetic field compressibility as shown in the present paper using a case study. It is found that the Alfvénic slow wind is more similar to fast wind rather than to the standard slow wind apart from velocity. This fact can be attributed to a different source region on the solar surface. Actually the standard slow wind comes from coronal streamers or active regions while the Alfvénic slow wind originates from the boundary of coronal holes sharing characteristics typical of fast wind.

The optical efficiencies of a solar trough concentrator are important to the whole thermal performance of the solar collector, and the outer surface of the tube absorber is a key interface of energy flux. So it is necessary to simulate and analyze the concentrated solar flux density distributions on the tube absorber of a parabolic trough solar collector for various sun beam incident angles, with main optical errors considered. Since the solar trough concentrators are linear focusing, it is much of interest to investigate the solar flux density distribution on the cross-section profile of the tube absorber, rather than the flux density distribution along the focal line direction. Although a few integral approaches based on the “solar cone” concept were developed to compute the concentrated flux density for some simple trough concentrator geometries, all those integral approaches needed special integration routines, meanwhile, the optical parameters and geometrical properties of collectors also couldn’t be changed conveniently. Flexible Monte Carlo ray trace (MCRT) methods are widely used to simulate the more accurate concentrated flux density distribution for compound parabolic solar trough concentrators, while generally they are quite time consuming. In this paper, we first mainly introduce a new backward ray tracing (BRT) method combined with the lumped effective solar cone, to simulate the cross-section flux density on the region of interest of the tube absorber. For BRT, bundles of rays are launched at absorber-surface points of interest, directly go through the glass cover of the absorber, strike on the uniformly sampled mirror segment centers in the close-related surface region of the parabolic reflector, and then direct to the effective solar cone around the incident sun beam direction after the virtual backward reflection. All the optical errors are convoluted into the effective solar cone. The brightness distribution of the effective solar cone is supposed to be circular Gaussian type. Then a parabolic trough solar collector of Euro Trough 150 is used as an example object to apply this BRT method. Euro Trough 150 is composed of RP3 mirror facets, with the focal length of 1.71m, aperture width of 5.77m, outer tube diameter of 0.07m. Also to verify the simulated flux density distributions, we establish a modified MCRT method. For this modified MCRT method, the random rays with weighted energy elements are launched in the close-related rectangle region in the aperture plane of the parabolic concentrator and the optical errors are statistically modeled in the stages of forward ray tracing process. Given the same concentrator geometric parameters and optical error values, the simulated results from these two ray tracing methods are in good consistence. The two highlights of this paper are the new optical simulation method, BRT, and figuring out the close-related mirror surface region for BRT and the close-related aperture region for MCRT in advance to effectively simulate the solar flux distribution on the absorber surface of a parabolic trough collector.

This paper briefly reviews a compact toroid reactor concept that addresses critical issues for forming, stabilizing and sustaining a field reversed configuration (FRC) with the use of plasma merging, plasma shaping, conducting shells, neutral beam injection (NBI). In this concept, an FRC plasma is generated by the merging of counter-helicity spheromaks produced by inductive discharges and sustained by the use of neutral beam injection (NBI). Plasma shaping, conducting shells, and the NBI would provide stabilization to global MHD modes. Although a specific FRC reactor design is outside the scope of the present paper, an example of a promising FRC reactor program is summarized based on the previously developed SPIRIT (Self-organized Plasmas by Induction, Reconnection and Injection Techniques) concept in order to connect this concept to the recently achieved the High Performance FRC plasmas obtained by Tri Alpha Energy [Binderbauer et al, Phys. Plasmas 22,056110, (2015)]. This paper includes a brief summary of the previous concept paper by M. Yamada et al, Plasma Fusion Res. 2, 004 (2007) and the recent experimental results from MRX.

Solar neutrinos offer a unique opportunity to study the interaction of neutrinos with matter, a sensitive search for potential new physics effects, and a probe of solar structure and solar system formation. This paper describes the broad physics program addressed by solar neutrino studies, presents the current suite of experiments programs, and describes several potential future detectors that could address the open questions in this field. This paper is a summary of a talk presented at the Neutrino 2014 conference in Boston.

The results of LSND and MiniBooNE, along with the recent papers on a possible reactor neutrino flux anomaly, give tantalizing hints of new physics. Models beyond the νSM have been developed to explain these results and involve one or more additional neutrinos that are non-interacting or “sterile.” Neutrino beams produced from the decay of muons in a racetrack-like decay ring provide a powerful way to study this potential new physics. In this paper, I will describe the facility, nuSTORM, and an appropriate far detector for neutrino oscillation searches at short baseline. I will present sensitivity plots that indicated that this experimental approach can provide well over 5 σ confirmation or rejection of the LSND/MinBooNE results.

Injection of high energy beams of neutral particles is a method for plasma heating in fusion devices. The ITER injector, and its prototype MITICA (Megavolt ITER Injector and Concept Advancement), are large extrapolations from existing devices. Therefore nu merical modeling is needed to set thermo - mechanical requirements for all beam - facing components. As the power and charge deposition originates from several sources (primary beam, co - accelerated electrons, and secondary production by beam - gas, beam - surface, and electron - surface interaction), the beam propagation along the beam line is simulated by comprehensive 3D models. This paper presents a comparative study between two codes: BTR has been used for several years in the design of the ITER HNB components; the SAMANTHA code was independently developed and includes additional phenomena, like secondary particles generated by collision of beam particles with the background gas. The code comparison is valuable in the perspective of the upcoming experimental oper ations, in order to prepare a reliable numerical support to the interpretation of experimental measurements in the beam test facilities. The power density maps calculated on the Electrostatic Residual Ion Dump (ERID) is chosen as the benchmark, as they dep end on the electric and magnetic fields as well as on the evolution of the beam species via interaction with the gas. Finally the paper shows additional results provided by SAMANTHA, like the power deposition onto the Cryopumps due to secondary electrons accelerated by the ERID fringe - field

The orbital dynamics around the Libration points of the classical circular restricted three-body problem (CR3BP) have been investigated in detail: in the last few decades, dynamical systems theory has provided invaluable analytical and numerical tools for understanding the dynamics of Libration Point Orbits (LPOs). The aim of this paper is to extend the model of the CR3BP to derive the LPOs in the vicinity of the Martian moon Phobos, which is becoming an appealing destination for scientific missions. The case of Phobos is particularly extreme, since the combination of both small mass-ratio and length-scale moves the collinear Libration manifold close to the moon’s surface. Thus, a model of this system must consider additional dynamical perturbations, in particular the complete gravity field of Phobos, which is highly-inhomogeneous. This is accomplished using a spherical harmonics series expansion, deriving an enhanced elliptic three-body model. In this paper, we show how methodologies from dynamical systems theory are applied in differential correction continuation schemes to this proposed nonlinear model of the dynamics near Phobos, to derive the structure of the dynamical substitutes of the LPOs in this new system. Results obtained show that the structure of the LPOs differs substantially from the classical case without harmonics. The proposed methodology allows us to identify natural periodic and quasi-periodic orbits that would provide unique low-cost opportunities for close-range observations around Phobos and high-performance landing/take-off pathways to and from Phobos’ surface, which could be exploited in upcoming missions targeting the exploration of this Martian moon.

This paper concerns the numerical solution of the BlackScholes PDE with a Neumann boundary condition on the right boundary. We consider finite difference schemes for the semi-discretization, which leads to a system of ODEs with corresponding matrix M. In this paper stability bounds for exp(tM) (t ≥ 0) are proved. A scaled version of the Euclidean norm, denoted by ‖ ⋅ ‖H is considered. The advection and diffusion term of the PDE are analyzed separately. It turns out that the Neumann boundary condition leads to a growth of ‖exp(tM)‖H with the number of grid points m for the pure advection problem.

This paper is offered as a response to the remarks regarding [1], as given in [2].This paper is offered as a response to the remarks regarding [1], as given in [2].

A single dielectric barrier discharge is a specific configuration for plasma actuators consisting of two electrodes, one coated by a dielectric material and the other is exposed to the air. The purpose of this paper is to study the characteristics of single dielectric barrier discharge (DBD) plasma actuator through numerical modeling. A mathematical model that represents the physical system is presented and the numerical simulations for specific geometry are discussed in this paper. With this model, we can study the physics of the plasma flow. The formulation of the governing equations are divided into two since the physical system can be distinctly separated; one is the electrostatic part and the other is on the fluid flow. The electrostatic part is formulated using the Maxwell’s equation which needs to be modified to incorporate the current frequency equation so that the system of equations becomes unsteady which is more realistic compared to a steady system of equations. The fluid flow part is formulated using the Navier-Stokes equations. The equations are re-represented using a vorticity term and stream function so that the flow characteristics can be clearly visualized. All equations are discretized using finite difference method. The discretized equations are then solved using the Gauss-Seidel iteration method. The numerical results show that the vorticity of the plasma is similar in pattern at each time interval. The highest magnitude of the vorticity occurs at the inner part near end of the upper electrode but this magnitude is different at each time. On varying the applied voltage, it is found that the peak vorticity also increases. Therefore, this shows that both the applied voltage and the geometry of the system influence the characteristics of the plasma flow.