Induction Vector Research Articles

Ways to Improve Wear Resistance and Damping Properties of Radial Bearings Taking into Account Inertial Forces

This article considers a radial sliding bearing of infinite length whose moving part consists of the support, the porous layer, and the liquid lubricant. The analysis of the existing design calculation methods for such sliding bearings shows that they are very approximate because they do not consider the inertial forces applied, the electric conductivity of the lubricant, the permeability anisotropy, as well as the impacts of the electric field vector, magnetic induction vector, and incomplete filling of the working gap (pre-accident condition). The authors demonstrate how these factors impact the stable operation of the device facilitating the hydrodynamic regime. The authors find the asymptotic solution for the zero, first, and second approximation taking into account the inertial forces for the “thin layer”. By solving the produced equations using the Gauss-Seidel method, the authors determine the key operating parameters of the friction couple in question: the carrying capacity and the friction force. The authors provide an impact assessment for the parameters characterizing the permeability of the porous coating, the electric conductivity, and viscosity of the lubricant, as well as the length of the loaded area and the impacts of inertial forces on the carrying capacity and the friction force.

Natural Magneto-velocity Coordinate System for Satellite Attitude Stabilization: The Concept and Kinematic Analysis

An artificial Earth satellite with an electric charge and an intrinsic magnetic moment is considered. Due to the geomagnetic field, the satellite experiences the influence of the Lorentz and magnetic torques. To set the angular position of the satellite, we introduce natural coordinate system associated with the directions of geomagnetic induction vector and Lorentz force vector which is orthogonal both to the geomagnetic induction and relative velocity of the satellite. It is shown that such a natural magneto-velocity coordinate system is convenient for attitude stabilization of a satellite operating in the mode of scanning the Earth's surface. The properties of the trajectory of the satellite axis on the Earth's surface are analysed. The rotation tensor connecting the natural magneto-velocity and the orbital coordinate systems is obtained. The angular velocity of the natural magneto-velocity trihedron is found. Kinematic differential equations for the unit vectors of the natural magneto-velocity coordinate system are derived.

Parametric vibrations of piezoelectric viscoelastic cylindrical panels taking into account transverse shear deformations

The paper presents a numerical-analytical approach to solving problems of parametric vibrations of layered hinged piezoelectric viscoelastic cylindrical panels under electromechanical harmonic loading. The mathematical model is constructed using mechanical hypotheses about layer-by-layer approximation of shear deformations by quadratic functions on the thickness of panel, which are supplemented by adequate hypotheses on the distribution of electric field quantities when the components of the electric field strength vector and the normal component of the electric induction vector are different from zero. The dissipative properties of materials are taken into account on the basis of the theory of linear viscoelectric elasticity. To solve the problems, a technique based on the use of the variation principle and the representation of the required quantities in the form of decomposition into double trigonometric series has been developed. This makes it possible to reduce the considered problems to Mathieu-Hill-type equations taking into account energy dissipation, which are solved by the method of harmonic linearization, which allows to determine the boundaries of the regions of dynamic instability.

Efficiency Increasing of Traction Electric Drives with Induction Motors and Vector Control System

Efficiency Increasing of Traction Electric Drives with Induction Motors and Vector Control System

Модель Ізінга для опису магнітних властивостей елементів системи керування авіаційним двигуном

The creation of competitive engines is impossible without the development and implementation of new materials and design and technological solutions. At present, in the engines, nickel alloys obtained by directional crystallization are widely used, including monocrystalline, granular alloys. The use of various composite materials, permanent joints from dissimilar materials is constantly expanding, extensive research is being carried out to create a structure from monolithic ceramics and intermetallic compounds. The successful introduction of unconventional materials is impossible without a thorough study of their structural strength, magnetic properties, features of deformation, and destruction, taking into account the specifics of these materials when developing the design and manufacturing technology of a part or engine unit. The article discusses a software package for the optimal design of control system elements for aircraft gas turbine engines using a description of their magnetic properties. Due to the modular structure of the optimization program, various optimization procedures and calculation programs can be used. It was determined that, for the Ising model, the formation of domains with a given spread of spins at a temperature T and a vector of magnetic induction B is calculated array element using a random number generator. The number of tests L depends on the size of the sample. In the Ising model, all parts of the N*N system are contenders for testing. So, Step corresponds to the number of Monte Carlo steps. Since the parts are selected once on average, it is possible to select one particle several times or not to select it at all. Therefore, the Step value should be significantly greater than one. For a convenient implementation of a certain model, its application with a graphical magnetization interface with a different number of iterations has been considered. When executing the command file, the following should be performed: building a geometric model, building a finite element mesh, applying loads, calculating the stress-strain state (SSS), displaying the results.

Tectonic controls on magmatic systems: Evidence from a three-dimensional anisotropic electrical resistivity model of Ceboruco Volcano

This paper presents results from a magnetotelluric survey at Ceboruco Volcano in Mexico. The observed data require an anisotropic 3-D electrical resistivity model which links a near-surface geothermal reservoir to the magmatic system and finally to the local tectonic setting.Ceboruco is an active stratovolcano, which is located in the Tepic-Zacoalco Rift and is part of the Trans-Mexican Volcanic Belt. Together with Chapala and Colima, the Tepic-Zacoalco Rift forms a triple rift system, which developed as a consequence of the subduction of the Rivera and Cocos oceanic plates beneath the North American continental crust. Ceboruco is the largest and most active volcano in the region.Broadband magnetotelluric data were collected at 25 sites distributed on and around Ceboruco Volcano during a two-week campaign. The survey focused on the electrical resistivity distribution to characterize the geothermal potential and the deep structure beneath the volcano. The data quality is very high in a wide period range between 10−4 and 102s and there is a consistent data pattern at all sites. For sites located on the volcano, topographical effects dominate the shortest periods. At all sites a highly conductive layer is implied for periods below 1 s, and a spatially constant phase split and coincident small induction vectors are observed to the long period end.The 3-D isotropic inversion of the data yields an excellent data fit for short and intermediate periods and reveals a shallow magma storage and an extensive hydrothermal reservoir between 1 km a.s.l. and approximately 2 km b.s.l. At greater depth, the inversion algorithm generates large-scale high resistivity contrasts, reaching far outside the area of investigation. The resulting structures are inconsistent with the known geological setting and are considered to be artifacts of the isotropic inversion. We present an alternative model, which includes two anisotropic layers below 10 km depth. The conductive principal axes of the anisotropy are consistent with the local rifting direction in the Tepic-Zacoalco Rift and relate to a ductile deformation of the host rock and a large mush zone at mid- to lower-crustal depths.

Polimeryzacja aniliny w środowisku stałego pola magnetycznego

Polyaniline is an example of an electronically conducting polymer. During the oxidation of the polymer, positive charges appear in its structure, which must be compensated for e.g. by the presence of anions in the polymer layer. The form of polyaniline depends on both the degree of oxidation and the degree of protonation of the polymer, i.e. the pH of the solution. Due to the ease of electrochemical preparation of polyaniline, as well as the possibility of full control of the course of the process, the influence of the constant magnetic field (s.p.m.) on the reaction of its preparation was additionally investigated. The cyclic voltammetry (CV) method was used for this purpose. Aniline polymerization processes were carried out on platinum, plate electrodes, not insulated (A) and insulated on two different sides with Teflon, with surfaces directed parallel to the line of force of the s.p.m. (To beat). Research on the electrochemical preparation of polyaniline in s.p.m. allowed to conclude that the following factors affect the magnitude of the current in the tested process: (i) the magnitude of the magnetic induction vector B, (ii) the position of the electrode plane in relation to the direction of the vector B, (iii) the type of electrode (insulated on one side or not). Impact on the impact of s.p.m. the magnetic properties (e.g. paramagnetic, diamagnetic) of the particles participating in the electrochemical reaction, as well as their charge (+/-), also had an effect on the electrochemical polymerization processes. Based on the experimental results, the mechanism of the influence of s.p.m. was proposed. on the tested electrochemical reactions. This mechanism was based, inter alia, on the formation of the magnetohydrodynamic effect (MHD), which causes a change in the speed of transport of the reacting substances to the electrode, the magnetohydrodynamic movement of the electrolyte and the change in the kinetics of electrode processes. For the tested process, changes in the rate constants of electrochemical reactions (ks) as a result of external action of s.p.m. were around 30%.

Numerical simulations of vector hysteresis processes via the Preisach model and the Energy Based Model: An application to Fe-Si laminated alloys

The paper presents the state of the art and the problems already open in modelling the hysteresis phenomenon in 2-D for laminated soft ferromagnetic materials. Firstly, a thorough experimental investigation has been carried out at a very low frequency by a single disk tester (SDT) for a specimen of innovative NGO electrical steel sheet. Scalar, rotational and elliptic magnetization processes have been experimentally measured under controlled waveforms of the magnetic induction vector thanks to an effective digital feedback algorithm. Two numerical model of hysteresis have been taken into account to reproduce the measured magnetization processes: the vector Preisach model (VPM) and the Energy Based Model (EBM). The main advantages and limitations in the use of the two hysteresis models are comprehensively analysed and discussed, taking into consideration both the problem of identification and the simulation results. In particular, the effective capability of the models to reproduce the vector field trajectories and to predict the hysteresis power losses has been shown. Conclusive considerations involve the memory usage and the computational time for the low level of abstraction implementation of the two hysteresis models.

Transient Attitude Motion of TNS-0#2 Nanosatellite during Atmosphere Re-Entry

Attitude motion reconstruction of the Technological NanoSatellite TNS-0 #2 during the last month of its mission is presented in the paper. The satellite was designed to test the performance of the data transmission via the Globalstar communication system. This system successfully provided telemetry (even during its atmosphere re-entry) up to an altitude of 156 km. Satellite attitude data for this phase is analyzed in the paper. The nominal satellite attitude represents its passive stabilization along a geomagnetic field induction vector. The satellite was equipped with a permanent magnet and hysteresis dampers. The permanent magnet axis tracked the local geomagnetic field direction with an accuracy of about 15 degrees for almost two years of the mission. Rapid altitude decay during the last month of operation resulted in the transition from the magnetic stabilization to the aerodynamic stabilization of the satellite. The details of the initial tumbling motion after the launch, magnetic stabilization, transition phase prior to the aerodynamic stabilization, and subsequent satellite motion in the aerodynamic stabilization mode are presented.

Establishment of a Bivector Genetic Transformation System in Recalcitrant Maize Inbred Lines

Maize is an important grain crop with high nutritional value. An effective transformation system is crucial for the genetic improvement of maize traits, but many important maize inbred lines remained recalcitrant to transformation. In this study, we developed a bivector transformation system that worked well in two recalcitrant maize inbred lines. This system included an induction vector (ZmBBM-ZmWUS) and an indicator vector (GFP), using microprojectile bombardment technology combined with Agrobacterium-mediated transformation. We found that the Zheng58 and Mo17 recalcitrant inbred lines could be transformed with this system. The whole transformation cycle lasted only 52 days, 38 days less than the traditional transformation cycle. Additionally, it was possible to eliminate inference of the induction vector and obtained progenies with only the target gene. Our results suggested that the bivector system was an optimization of the current maize transformation methods and could potentially be used in genetic improvement of maize inbred lines.

ГЕОДИНАМІКА

Interest in research on the detection of earthquake (EQ) precursors is growing year by year. In this direction, the paper analysed the results of earlier studies, as well as positive results of some studies conducted in the last 5 years. In particular, during the study of EQs, ultra-low frequency (ULF) precursors attract special attention. The study compared the results of electromagnetic (EM) monitoring studies conducted in the ULF range in earlier years and the results of EM monitoring studies conducted in the last 5 years have been compared. The positive results of the researchers investigating the changes in the EM field before the EQ in the ULF range were reviewed. Thus, ULF anomalies from relatively weak (with 4<Mw<5) and shallow (with a depth of less than 50 km) EQs were repeatedly observed in 2017 in Indonesia. Before strong EQs, ULF promising EQ precursors were revealed. High ULF amplitude anomalies were recorded before the 2011 Tohoku megaEQ. Anomalous changes of the Earth's induction vector were identified in 6 observatories in Japan. Similar anomalies were also recorded in the ULF range (0.001-0.083 Hz) by the Teoloyucan (Mexico) and Tucson (the United States) geomagnetic observatories from August 1 to September 16, 2017, before the Chiapas EQ in Mexico with a magnitude 8.1. On the whole, the research discovered several dozen EM precursors of EQs with different amplitude, spectral and time parameters. The study was based on the analysis of numerous data for the periods 1976-2010 and 2007-2016 conducted by various researchers. In addition, an original approach is proposed. It consists in the study of geoelectric field changes (ULF precursors of EQs) as they are more sensitive. Processing and interpreting these changes can lead to precise detection of EQ precursors. Thus, this makes it possible to identify geodynamic active zones in which an EQ may occur.

Time response analysis for two-phase PMSM with two-sectional phase windings

A new approach to investigation of two-phase PMSM control methods on the level of phase windings sections is presented. For two-phase PMSM with two-sectional windings all control methods are considered from a unified position. Section and phase usage variants implementable at all possible section connection schemes are determined and classified; armature magnetic induction vector amplitudes and angle positions are calculated. The vectors are grouped by graphical representation, phase usage variant and section connection scheme into sets, number of which leading to non-zero vectors and the zero vector is determined. A simulation is carried out, speed time response curves are calculated and compared; the affecting of section connection scheme and phase usage variant on speed transition time and idle speed is ascertained; groups are discovered, section connection schemes can be attributed to. The obtained results can be used in demand by drive developers to select the most suitable PMSM control method.

Multichannel information-measuring system on an unmanned aircraft for measuring the total induction vector of the Earth's magnetic field

A prototype of a multichannel information-measuring system for measuring the vector of induction of the Earth's magnetic field (EMF) was developed, manufactured and successfully passed a complex of preliminary tests, which is applicable for the further development of technology for airborne geophysical reconnaissance at different altitudes from an unmanned aerial vehicle (UAV) and a software product that allows with the measurement of the value of the induction modulus of the EMF, determine the values of its components.

Influence of the near-surface regions of the space charge in semiconductor crystals on defect transformation stimulated by action of magnetic fields

The mechanisms of electromagnetic radiation in the near-surface regions of semiconductors depleted of the majority charge carriers under action of magnetic fields, the induction vector of which is parallel to the surface of the crystal, have been analyzed. The relationships for estimating the radiation power of space charge regions have been derived.

Dynamic of orientation processes in liquid crystal systems of technical devices

The relaxation properties of nematic liquid crystals by the pulsed method of a fixed distance in a rotating magnetic field are investigated. The adequacy of the solution of the equation of motion of the nematic director in the conditions of asynchronous motion of the director and the magnetic field induction vector was experimentally confirmed. The values of the rotational viscosity coefficient and the orientation relaxation time that characterize the parameters of devices with a liquid-crystal working medium in a wide range of pressures and temperatures are calculated. In the framework of the free volume theory, the dependence of the rotational viscosity coefficient on temperature and pressure is analyzed.

Vector Hysteresis Processes for Innovative Fe-Si Magnetic Powder Cores: Experiments and Neural Network Modeling

A thorough investigation of the 2-D hysteresis processes under arbitrary excitations was carried out for a specimen of innovative Fe-Si magnetic powder material. The vector experimental measurements were first performed via a single disk tester (SDT) apparatus under a controlled magnetic induction field, taking into account circular, elliptic, and scalar processes. The experimental data relative to the circular loops were utilized to identify a vector model of hysteresis based on feedforward neural networks (NNs), having as an input the magnetic induction vector B and as an output the magnetic field vector H. Then the model was validated by the simulation of the other experimental hysteresis processes. The comparison between calculated and measured loops evidenced the capability of the model in both the reconstruction of the magnetic field trajectory and the prediction of the power loss under various excitation waveforms. Finally, the computational efficiency of the model makes it suitable for future application in finite element analysis (FEA).

EVALUATING THE TRANSPORT SYSTEM EFFICIENCY OF PUMPING ELECTRICALLY CONDUCTIVE LIQUID BASED ON THE RESULTS OF MATHEMATICAL MODELING

Today in many industries there is a need to pump electrically conductive fluids. In contrast to classical hydrodynamics, MHD modeling requires the simultaneous solution of the equations of hydrodynamics and electrodynamics, which significantly complicates the modeling process. For electrically conductive fluids, such a number of experimental studies has not yet been conducted, in addition, the dependencies are complicated by the influence of the magnetic field and the need to take into account their magnitude. An urgent task is to determine the dependences of the pressure losses of local resistances during the flow of electromagnetic fluids on electromagnetic and hydrodynamic parameters. The development of computational hydrodynamics in recent years has led to the fact that the use of CFD-calculations can practically replace valuable experimental studies of electrically conductive fluids by mathematical modeling. Experimental studies are complicated by the use of powerful electromagnets and a variety of electrically conductive fluids, which often have not only electromagnetic properties, but are often non-Newtonian. Based on the numerical simulation of the flow of conductive fluid in the pipeline elbow, the dependences of the pressure losses at the bend in the elbow were determined by solving the Navier – Stokes equations averaged according to Reynolds. The magnetic field has a significant effect on the diagram of the velocity before and after the turn in the knee due to the fact that the magnetic induction vector in either the first or second section is perpendicular to the tube. At relatively small values of Reynolds numbers, the effect of the magnetic field is very significant, which increases the local resistance coefficient by more than 15 times compared to the coefficient without the action of the magnetic field.

МАТЕМАТИЧНА МОДЕЛЬ НАДПРОВIДНОГОМАГНIТНОГО ПIДВIСУ В НЕВАГОМОСТI

Paper provides a research of the mathematical model of a superconducting magnetic suspension in zero gravity. The model consists of a special configuration of the superconducting inductors and uniform magnetic field. The stabilization of suspension in dependence of angle between the magnetic field induction vector and the axis of the inductance coil that is a suspended «free» rigid body is researched. Analysis of the model on stability of equilibrium is carried out and the conditions of spatial magnetic well existence providing the contactless confinement of a rigid body in zero gravity are found.

Формирование и аналитическое описание базовых векторов двухфазного вентильного двигателя с двухсекционной фазной обмоткой

The article describes a new approach to the consideration of physical processes in switched motors with two-section phase windings, in which the section is taken as an elementary analysis unit. A system of designations for sections and phases is proposed, which can be extended to an arbitrary number of phases in the motor and sections in the phase. The possible states of the phases and sections that characterize the participation of each of them in producing the electromagnetic torque are determined. For a two-phase switched motor, possible section connection diagrams, phase engagement methods corresponding to these diagrams, and sets of basic armature magnetic induction vectors are determined. An analytical description of the basic vectors in the form of sets, the elements of which contain information about the amplitude and phase shift, is performed. The sets of basic vectors in a two-phase motor with a two-section phase winding are compared with those in a three-phase motor with a single-section phase winding, which is currently most widely used. The obtained description of the basic vector sets can serve as a basis for analytically representing a digital device for controlling a two-phase switched motor, and also as a basis for implementing control methods based on vector pulse width modulation.

INVESTIGATING THE IMPACT OF AN EXTERNAL INFLUENCE ON THE DYNAMIC BEHAVIOR OF DISLOCATIONS IN SILICON CRYSTALS

The results of studying of the influence of a constant magnetic field on the dynamic behavior of dislocations in the crystalline block of an interferometer subsequently subjected to uniaxial mechanical tensile stress along the crystallographic axis of silicon are presented. The periodicity of the dilatation moire image after these influences, the average means free path of a dislocation in a crystal (block), the amount of slip, the average density of dislocations along the slip line, the relative deformation, and Young's modulus are calculated. To study the effect of a stable magnetic field on the dynamic behavior of dislocations in silicon crystals, a special three-block X-ray interferometer was fabricated in one of the blocks, and dislocations were introduced using the technique proposed by us. The experiments were carried out for various values of the magnetic field induction and mechanical stress. It is shown that the sequential action of these external influences leads to an increase in the starting stress, a decrease in the velocity of dislocation movement, a delay in the onset of dislocation movement, and the appearance of a hardening phenomenon. Experiments show that the displacement mobility characteristics are especially sensitive when the modulus of the magnetic induction vector reaches a certain threshold value for a given sample. It was shown that, in a sample containing silicon dislocations, the magnetic memory that appears after storage in a magnetic field is short-lived. It is found that the speed of movement of a dislocation in a magnetic field processed by a magnetic field, "then" subjected to mechanical stress (stretching), changes, but in practice the energy of its activation does not change. A theoretical analysis of the above experimental results is carried out, their scientific substantiation is given, all the factors associated with the phenomena observed in experiments are revealed.