scholarly journals Computational studies of hydrotoparaffin plugs in wells

2021 ◽  
Vol 2142 (1) ◽  
pp. 012008
Author(s):  
G R Izmaylova
Keyword(s):  
High Frequency ◽  
Western Siberia ◽  
Initial Conditions ◽  
Temperature Drop ◽  
Temperature Fields ◽  
Computational Studies ◽  
Numerical Implementation ◽  
Far North ◽  
Transfer Equations ◽  
High Frequency Electromagnetic Field

Abstract In Western Siberia and the Far North, complications caused by paraffin plugs in wells are not temporary. They are caused by ongoing factors, such as permafrost zones, a sharp temperature drop along the well, the high gas factor and water in the well products. The paper studies the possibility of using a high-frequency electromagnetic field to remove paraffin plugs inside the well. Mathematical modeling of the problem using a system of heat and mass transfer equations and boundary and initial conditions is described. The phase transition (melting of hydratoparaffin) is denoted by Stefan’s condition which is one of the boundary conditions. The problem does not have an analytical solution, so the numerical implementation of the solution is carried out. Graphs of dependences of melting limits on generator power, and distribution of temperature fields in wells are constructed.

Method of high frequency therapy at cows' mastitis during machine milking

2020 ◽  
pp. 9-12
Author(s):  
Viktor E. Lyubimov ◽  
Keyword(s):  
Dairy Cows ◽  
Electromagnetic Fields ◽  
High Frequency ◽  
High Efficiency ◽  
Environmentally Friendly ◽  
Ultrahigh Frequency ◽  
Machine Milking ◽  
High Frequency Electromagnetic Field ◽  
Milking Machine ◽  
Methods Of Treatment

Health of dairy cows ensures human health, so it is important that dairy products do not contain antibiotics that are used to treat any inflammation, including mastitis. In Russia at present, the problem of mastitis in cows exists with both attached and loose housing of cows. Mastitis of dairy cows are the great problem in milking husbandry. Losses from mastitis in milk yield can reach 15-20%. The main reasons for the occurrence of nonspecific mastitis of cows are the shortcomings of the working components of the milking machine: the degree of deterioration of the nipple rubber and the violation of machine milking technology (the reduction in pre-milking time and vacuum fluctuations account for 70% of all causes). Treatment of mastitis with antibiotics is effective, but not environmentally friendly and unacceptable. For the treatment of inflammation of the udder, it is necessary to use more environmentally friendly methods of treatment, one of which is the exposure to ultra-high frequency electromagnetic field tested by medicine. Use of three types of medical-mobile milking machines with the same method of exposure to ultrahigh-frequency electromagnetic fields on cow's nipples through electrodes in milking cups: LPDA-1-UHF, LPDA-2-UHF and LPDA-UHF-30 M, is described in the article. Author proved that cows with subclinical forms of mastitis recovered faster during milking with exposure to the ultrahigh frequency than when treated by antibiotics, and milking with the ultrahigh frequency device helps to recover 82% of the affected quarters with clinical forms and 100% of cows with subclinical forms of mastitis or with udder irritation. The high efficiency of the method of exposure to electromagnetic fields of the ultrahigh frequency during machine milking by means of medical-mobile milking machines LPDA-UHF for the prevention and treatment of mastitis of cows was shown.

Development of software and hardware complex of operative diagnostics of structural part of 35-220 kV overhead lines operated in Northern regions of Western Siberia

2018 ◽  
pp. 69-77
Author(s):  
S. V. Grigorieva ◽  
A. V. Olshansky
Keyword(s):  
Western Siberia ◽  
Technical Condition ◽  
Structural Part ◽  
Software Complex ◽  
Overhead Lines ◽  
Far North ◽  
Hardware Complex ◽  
Northern Regions ◽  
Software And Hardware ◽  
Overhead Power Lines

The article is devoted to the problems of maintenance of overhead power lines in the Far North of Western Siberia. For improvement of quality and reliability of power supply of consumers in the conditions of the Far North of Western Siberia, decrease in operational costs and volumes of the carried-out emergency works the hardware-software complex for expeditious inspection, assessment and forecasting of change of technical condition of constructive part of air lines (VL) of 35-220 kV is developed, the structure of the hardware-software complex of registration of the condition of constructive part of VL of 35-220 kV and structure of the hardware-software complex of storage., processing and analysis of the obtained data on the States of the constructive part of the VL 35-220 kV. 

scholarly journals Effect of high-frequency electromagnetic field on microstructure of mold flux

2020 ◽  
Vol 39 (1) ◽  
pp. 368-376
Author(s):  
Xingjuan Wang ◽  
Hebin Jin ◽  
Liguang Zhu ◽  
Ran Liu ◽  
Tushun Song
Keyword(s):  
Electromagnetic Field ◽  
High Frequency ◽  
Mold Flux ◽  
Film Structure ◽  
Glass Layer ◽  
Slag Film ◽  
Flux Flow ◽  
Layer Form ◽  
Finite Element Software ◽  
High Frequency Electromagnetic Field

AbstractSoft-contact of molten steel can be achieved by applying a high-frequency electromagnetic field above the mold of continuous casting, which can effectively eliminate surface defects and achieve billets with no cracks and no oscillation marks. It also has some influence on the mold flux. In this study, the effect of a high-frequency electromagnetic field (20 kHz) on a mold flux flow field was simulated using a finite element software, and the slag film was extracted using a slag film simulator. The effect of the high-frequency magnetic field on the microstructure of the mold flux was analyzed using X-ray diffraction, Raman spectroscopy, and mineral phase testing. The results show that the high-frequency electromagnetic field disrupts the orderly movement and increases the movement rate of the liquid flux. The precipitate phase of the slag film did not change, but the silicate dimer Q1 decreased, the chain Q2 increased, and the network degree was increased. The slag film structure changed from the original two-layer form of crystalline layer–glass layer into a three-layer form of crystal layer–glass layer–crystal, and the crystallization ratio increased by 35% on average. The grain-size melilite granularity was reduced from the original 0.12 to 0.005 mm.

The Generation of Switchable Polarized Currents in Nodal Ring Semimetals Using High-Frequency Periodic Driving

2021 ◽  
Author(s):  
Pei-Hao Fu ◽  
Qianqian Lv ◽  
Xiang-Long Yu ◽  
Jun-Feng Liu ◽  
Jiansheng Wu
Keyword(s):  
High Frequency ◽  
Surface Currents ◽  
Switching Effect ◽  
Fermi Arc ◽  
Periodically Driven ◽  
Weyl Semimetal ◽  
Spin Polarized ◽  
High Frequency Electromagnetic Field ◽  
Polarized Surface ◽  
Lead Device

Abstract A nodal ring semimetal (NRSM) can be driven to a spin-polarized NRSM or a spin-polarized Weyl semimetal (SWSM) by a high-frequency electromagnetic field. We investigate the conditions in realizing these phases and propose a switchable spin-polarized currents generator based on periodically driven NRSMs. Both bulk and surface polarized currents are investigated. The polarization of bulk current is sensitive to the amplitude of the driving field and robust against the direction and polarization of the driving, the opaqueness of the lead-device interface and the misalignment between the nodal ring and the interface, which provides sufficient flexibility in manipulating the devices. Similar switchable polarized surface currents are also expected, which is contributed by the Fermi arc surface state associated with the Weyl semimetal (WSM) phases. The generation of polarized currents and the polarization switching effect offer opportunities to design periodic driving controlled topological spintronics devices based on NRSMs.

scholarly journals ЗМІНА ЕЛЕКТРИЧНИХ ВЛАСТИВОСТЕЙ НАСІННЯ ПІД ВПЛИВОМ ВИСОКОЧАСТОТНОГО ЕЛЕКТРОМАГНІТНОГО ОПРОМІНЕННЯ

2014 ◽  
pp. 151-155
Author(s):  
О. М. Петровський
Keyword(s):  
Electromagnetic Field ◽  
High Frequency ◽  
Electric Properties ◽  
Electric Resistance ◽  
Active Resistance ◽  
Exchange Processes ◽  
High Frequency Electromagnetic Field ◽  
Stimulation Of

Розглянуті питання передпосівної стимуляції на-сіння високочастотним електромагнітним полем.Запропоновано спосіб опромінення насіння і визна-чення його електричних характеристик. На основібудови клітин визначені електричні властивості біо-логічної тканини, з якої складається насіння. Пока-зана зміна складових активного опору в залежностівід частоти струму. Експериментально доведено,що еквівалентну електричну схему неможливо звес-ти до простих випадків з’єднання опорів і ємностей,а саме насіння не можна вважати нейтральнимдіелектриком. Розроблена методика оцінки інтенси-вності обмінних процесів залежно від електричногоопору насіння. The questions of stimulation of seed before sowing are considered by the high-frequency electromagnetic field considered. The method of irradiation of seed and determination of him is offered electric descriptions. On the basis of structure of cages electric properties of biological fabric which seed consist of are certain. The change of constituents of active resistance is shown depending on frequency of current. It is experimentally proved that it is impossible to erect an equivalent electric chart to the simple cases of connection of resistances and capacities, namely seed can not be considered a neutral dielectric. The method of estimation of intensity of exchange processes  is developed depending on electric resistance of seed.

scholarly journals On the Sensitivity of the Simulated Diurnal Cycle of Precipitation to 3-Hourly Radiosonde Assimilation: A Case Study over the Western Maritime Continent

2021 ◽  
Vol 149 (10) ◽  
pp. 3449-3468
Author(s):  
Joshua Chun Kwang Lee ◽  
Anurag Dipankar ◽  
Xiang-Yu Huang
Keyword(s):  
Diurnal Cycle ◽  
High Frequency ◽  
Initial Conditions ◽  
Rainfall Variability ◽  
Weather Prediction ◽  
Radiosonde Data ◽  
Western Coast ◽  
Maritime Continent ◽  
Model Biases ◽  
Diurnal Cycle Of Precipitation

AbstractThe diurnal cycle is the most prominent mode of rainfall variability in the tropics, governed mainly by the strong solar heating and land–sea interactions that trigger convection. Over the western Maritime Continent, complex orographic and coastal effects can also play an important role. Weather and climate models often struggle to represent these physical processes, resulting in substantial model biases in simulations over the region. For numerical weather prediction, these biases manifest themselves in the initial conditions, leading to phase and amplitude errors in the diurnal cycle of precipitation. Using a tropical convective-scale data assimilation system, we assimilate 3-hourly radiosonde data from the pilot field campaign of the Years of Maritime Continent, in addition to existing available observations, to diagnose the model biases and assess the relative impacts of the additional wind, temperature, and moisture information on the simulated diurnal cycle of precipitation over the western coast of Sumatra. We show how assimilating such high-frequency in situ observations can improve the simulated diurnal cycle, verified against satellite-derived precipitation, radar-derived precipitation, and rain gauge data. The improvements are due to a better representation of the sea breeze and increased available moisture in the lowest 4 km prior to peak convection. Assimilating wind information alone was sufficient to improve the simulations. We also highlight how during the assimilation, certain multivariate background error constraints and moisture addition in an ad hoc manner can negatively impact the simulations. Other approaches should be explored to better exploit information from such high-frequency observations over this region.

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