Search

The paper discusses the problems arising during quality control of the raw materials (e.g., borehole fluid, crude oil, and oil–water emulsions) in the processes of their production, conditioning for transport, and processing. It is shown, that the existing means of express control of oil quality have low accuracy and insufficient speed of measuring oil characteristics. To ensure the quality of oil and purity of the separated ballast water, their additional purification is necessary. To perform the express control of oil characteristics (properties) during its production, conditioning and transportation, a proton magnetic resonance relaxometer and a multiparametric flow-through measuring complex with a representative sampling system have been developed. A method of nuclear (proton) magnetic resonance relaxometry, configuration and functioning algorithm of the measuring complex, as well as the structure and operation of the proton magnetic resonance relaxometer are described. Equations describing technical, electromagnetic, and circuit parameters of the relaxometer have been obtained. The relaxometer underwent metrological testing as part of the measuring complex during express control of the properties of oil samples. The following measurement errors of the characteristics of borehole fluid, crude oil, oil–water emulsions, and ballast water separated from oil were obtained: ±1% (relative error) for water content in oil in the range from 0 to 100%; ±0.2 mg/L for salt concentration in water in the range from 0 to 10 g/L; ±0.3% (relative error) for sulfur content in oil in the range from 0.1 to 8.0 abs.%; ±1.47 kg/m3 for oil density in the extended range from 700 to 1100 kg/m3; and ±0.13 mm2/s for kinematic viscosity of oil in the range from 0 to 350 mm2/s. The oil samples were characterized using analytical laboratory techniques. The introduced measuring complex enables data verification based on several parameters obtained using proton magnetic resonance relaxometry. The developed flow-through measuring complex can be used when controlling a multifunctional automated digital smart well, as well as equipment for separating water from the oil–water emulsions and treating produced water. [ABSTRACT FROM AUTHOR]

The development of metamaterials has led to the search and selection of effective methods for radio wave nondestructive testing of their electrophysical parameters. The existing approaches to testing, based on the recovery of the effective electrophysical parameters of metamaterials from the reflection and transmission coefficients of an electromagnetic wave, have low reliability and do not provide the local inspection of the parameters. In this paper, we propose for the first time a radio-wave method for local inspection of complex dielectric and magnetic permeabilities, as well as the thickness of flat-layered samples of metamaterials on a metal substrate using surface electromagnetic waves of the microwave range. The method is based on solving the inverse problem of determining the effective electrophysical parameters of a metamaterial from the frequency dependence of the complex attenuation coefficient of the field of a surface electromagnetic wave excited in the sample under study. In this case, the electrophysical parameters of the metamaterial are represented in the form of parametric frequency functions in accordance with the Drude–Lorentz dispersion models, and the solution of the inverse problem is reduced to minimizing the objective function constructed from the discrepancy between the experimental and calculated theoretical values of the attenuation coefficients of the surface electromagnetic wave field on a grid of discrete frequencies. The structure of the measuring complex that implements the proposed inspection method is presented. A sample of a flat-layered metamaterial based on SRR elements with a region of negative refraction in the frequency range of 10.06–10.64 GHz was investigated for the numerical and experimental verification of the method. Experimental verification has shown that the local values of the effective electrophysical parameters of the studied metamaterial differ from the calculated ones by no more than 10%. [ABSTRACT FROM AUTHOR]

In this paper, the hardware-software high resolution measuring system for studying the spatial and spectral distributions of the radiation intensity of a magnetron discharge is described. The emission spectra are recorded and processed for subsequent determination of the temperature and density of plasma electrons. These parameters are calculated on the basis of a technique suggesting the absence of ionization equilibrium and the Boltzmann distribution of populations of energy levels of the plasma-forming gas. The data on the electron density, atomic distributions by excited states, and the degree of their deviation from equilibrium in the entire volume of the discharge are presented. [ABSTRACT FROM AUTHOR]

More accurate navigation systems are always required for autonomous unmanned underwater vehicles (AUUV)s under various circumstances. In this paper, a measuring complex of a heavy unmanned underwater vehicle (UUV) was investigated. The measuring complex consists of an inertial navigation platform system, a Doppler lag (DL) and an estimation algorithm. During a relatively long-term voyage of an UUV without surfacing and correction from buoys and stationary stations, errors of the measuring complex will increase over time. The increase in errors is caused by an increase in the deviation angles of the gyro platform relative to the accompanying trihedron of the selected coordinate system. To reduce these angles, correction is used in the structure of the inertial navigation system (INS) using a linear regulator. To increase accuracy, it is proposed to take into account the nonlinear features of INS errors; an adaptive nonlinear Kalman filter and a nonlinear controller were used in the correction scheme. Considering that, a modified nonlinear Kalman filter and a regulator in the measuring complex are proposed to improve the accuracy of the measurement information, and modification of the nonlinear Kalman filter was performed through a genetic algorithm, in which the regulator was developed by the State Dependent Coefficient (SDC) method of the formulated model. Modeling combined with a semi-natural experiment with a real inertial navigation system for the UUV demonstrated the efficiency and effectiveness of the proposed algorithms. [ABSTRACT FROM AUTHOR]