scholarly journals DIRECT OBSERVATION OF HIGH-TEMPERATURE AREAS OF METAL MELT AT OXYGEN CONVERTER BLOWING WITH LOW VOLTAGE APPLICATION

2021 ◽  
Vol 17 (4) ◽  
pp. 44-54
Author(s):  
Sergiy Semykin ◽  
Tetiana Golub ◽  
Sergiy Dudchenko
Keyword(s):  
High Temperature ◽  
Reaction Zone ◽  
Potential Application ◽  
Low Voltage ◽  
Video Recording ◽  
Negative Polarity ◽  
Visual Observation ◽  
Reaction Zones ◽  
Voltage Potential ◽  
Bottom Blowing

Introduction. The process of oxygen conversion, despite the existing improvements, can be supplemented by physical methods of influence, including the unconventional method of applying low-voltage potential developed at the Iron and Steel Institute of the NAS of Ukraine.Problem Statement. The studies of the method of low-voltage potential application on 60, 160 and 250 ton converters have shown that the technology intensifies thermophysical and hydrodynamic processes in the gasslag-metal system and increases the converter process efficiency.Purpose. The purpose of this research is to study the features of the influence on the reaction zones of the low voltage potential application at four blowing options with the use of high-temperature physical model.Materials and Methods. A physical model that simulates the top, bottom and combined oxygen blowing under low-voltage potential application of different polarity on the lance has been used. An insert of a transparent quartz plate is made in one of the walls for visual observation and video recording. The top blowing is conductedwith two nozzle lance (nozzle diameter 1.7 mm with an angle of 30 ° to the lance). The bottom blowing is conducted with a bottom tuyere with a 1.5 mm diameter central nozzle. Combined blowing is realized by a combination ofthese options.Results. The visual observation of the reaction zones with different blowing options has shown that the highest temperature and the largest dimensions of the brightest parts of the bath correspond to the combined blowing, while the lowest ones are reported for the bottom blowing. While applying the low-voltage potential method it has been established that the reaction zone is longer at the positive polarity on the lance, during the period of silicon oxidation, and at the negative polarity on the lance, during the period of intense carbon oxidation. The video of gas bubbles flotation, probably CO, has shown that the bubbles are formed more intensively in thecase of negative polarity on the lance.Conclusions. The applied technique has allowed estimating the influence of low-voltage potential application on the geometric parameters of the reaction zone.

scholarly journals Improving the Efficiency of the Low-Voltage Potential Application Method at Top Oxygen Blowing in Converter

2020 ◽  
Vol 16 (2) ◽  
pp. 79-86
Author(s):  
S.I. Semykin ◽  
◽  
T.S. Golub ◽  
S.O. Dudchenko ◽  
◽  
...  
Keyword(s):  
Potential Application ◽  
Low Voltage ◽  
Application Method ◽  
Voltage Potential

scholarly journals Improving the Efficiency of the Low-Voltage Potential Application Method at Top Oxygen Blowing in Converter

2020 ◽  
Vol 16 (2) ◽  
pp. 72-79
Author(s):  
S.I. Semykin ◽  
◽  
T.S. Golub ◽  
S.O. Dudchenko ◽  
◽  
...  
Keyword(s):  
Potential Application ◽  
Low Voltage ◽  
Application Method ◽  
Voltage Potential

scholarly journals A Novel Kinematically Redundant Planar Parallel Robot Manipulator With Full Rotatability

2018 ◽  
Vol 11 (1) ◽  
Author(s):  
Nicholas Baron ◽  
Andrew Philippides ◽  
Nicolas Rojas
Keyword(s):  
Potential Application ◽  
Robot Manipulator ◽  
Video Recording ◽  
Parallel Robot ◽  
Singularity Analysis ◽  
Geometric Method ◽  
Forward Kinematics ◽  
Online Video ◽  
End Effector ◽  
Moving Platform

This paper presents a novel kinematically redundant planar parallel robot manipulator, which has full rotatability. The proposed robot manipulator has an architecture that corresponds to a fundamental truss, meaning that it does not contain internal rigid structures when the actuators are locked. This also implies that its rigidity is not inherited from more general architectures or resulting from the combination of other fundamental structures. The introduced topology is a departure from the standard 3-RPR (or 3-RRR) mechanism on which most kinematically redundant planar parallel robot manipulators are based. The robot manipulator consists of a moving platform that is connected to the base via two RRR legs and connected to a ternary link, which is joined to the base by a passive revolute joint, via two other RRR legs. The resulting robot mechanism is kinematically redundant, being able to avoid the production of singularities and having unlimited rotational capability. The inverse and forward kinematics analyses of this novel robot manipulator are derived using distance-based techniques, and the singularity analysis is performed using a geometric method based on the properties of instantaneous centers of rotation. An example robot mechanism is analyzed numerically and physically tested; and a test trajectory where the end effector completes a full cycle rotation is reported. A link to an online video recording of such a capability, along with the avoidance of singularities and a potential application, is also provided.

scholarly journals Rearing system and behavioural adaptation of laying hens to furnished cages

2008 ◽  
Vol 38 (7) ◽  
pp. 1997-2003 ◽  
Author(s):  
Victor Fernando Büttow Roll ◽  
Gustavo Adolfo Maria Levrino ◽  
Ricardo Cepero Briz
Keyword(s):  
Laying Hens ◽  
Video Recording ◽  
Visual Observation ◽  
Nest Box ◽  
Behavioural Adaptation ◽  
Direct Visual Observation ◽  
Cage Rearing ◽  
Sand Bath

The influences of floor and cage-rearing on behavioural adaptation to furnished cages were investigated in laying hens. Two groups of 180 Isa Brown commercial layer pullets were reared in cages (CR) or floor pens (FR) and transferred to furnished cages, where their behavioural adaptation was observed throughout the laying period (18-78 wks of age). At 17 weeks of age, hens were placed in one of the 36 furnished cages with 10 birds in each cage, each containing a nest box, perches, a dust bath, and abrasive strips. At 50 and 54 weeks of age, direct visual observation and video recording were used to assess hen’s behaviour. From 21 weeks of age, the dust-bath activities of leg-banded hens in eight cages per treatment were recorded. The amount of time spent walking was higher (3.5% vs. 1.8%) and perching was lower (7.5% vs. 13.4%) in CR hens than in FR hens (P<0.05). The use of dust baths and dust bathing behaviour increased throughout the laying period. The proportion of hens present at the sand bath area increased from 9.2% at 21 weeks to 21.4% at 72 weeks and the proportion of hens dust bathing increased from 4.7% to 21.0% (P<0.05). At 72 weeks of age, all dust-bath parameters were higher (P<0.05) in FR hens than in CR hens.

scholarly journals LASER SYSTEM FOR STUDYING THE DYNAMICS OF HIGH TEMPERATURE COMBUSTION

2019 ◽  
Vol 4 (2) ◽  
pp. 154-162
Author(s):  
Lin Li ◽  
Fedor Gubarev ◽  
Andrei Mostovshchikov ◽  
Alexander Ilyin
Keyword(s):  
High Temperature ◽  
Narrow Band ◽  
Laser System ◽  
Combustion Process ◽  
Visual Observation ◽  
Copper Bromide ◽  
Temperature Combustion ◽  
Temporal And Spatial ◽  
Combustion Processes ◽  
High Temperature Combustion

The paper is devoted to development of methods for studying the dynamics of high-temperature combustion of aluminum nanopowder.The difficulty in studying the combustion of nanopowders is the high temperature and intensity of light emissionduring the combustion process, which makes the visual observation virtually impossible.The paper discusses various schemes using laser radiation to study the combustion processes of metal nanopowders.Particular mentions the use of the laser monitor based on an active medium on copper bromide vapor to study the combustion process of various powders and mixtures.The laser monitor combines the functions of the narrow-band laser illuminator and the brightness amplifier, thereby achieving the visualization at a narrow gain wavelength. Therefore, the laser monitor can be used to observe the changes in the surface of a burning sample with high temporal and spatial resolution.

scholarly journals Thin-film chemical expansion of ceria based solid solutions: laser vibrometry study

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Hendrik Wulfmeier ◽  
Dhyan Kohlmann ◽  
Thomas Defferriere ◽  
Carsten Steiner ◽  
Ralf Moos ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
High Temperature ◽  
Film Thickness ◽  
Solid Solutions ◽  
Low Voltage ◽  
Excitation Frequency ◽  
Dimensional Change ◽  
Potential Core ◽  
Chemical Expansion

Abstract The chemical expansion of Pr0.1Ce0.9O2–δ (PCO) and CeO2–δ thin films is investigated in the temperature range between 600 °C and 800 °C by laser Doppler vibrometry (LDV). It enables non-contact determination of nanometer scale changes in film thickness at high temperatures. The present study is the first systematic and detailed investigation of chemical expansion of doped and undoped ceria thin films at temperatures above 650 °C. The thin films were deposited on yttria stabilized zirconia substrates (YSZ), operated as an electrochemical oxygen pump, to periodically adjust the oxygen activity in the films, leading to reversible expansion and contraction of the film. This further leads to stresses in the underlying YSZ substrates, accompanied by bending of the overall devices. Film thickness changes and sample bending are found to reach up to 10 and several hundred nanometers, respectively, at excitation frequencies from 0.1 to 10 Hz and applied voltages from 0–0.75 V for PCO and 0–1 V for ceria. At low frequencies, equilibrium conditions are approached. As a consequence maximum thin-film expansion of PCO is expected due to full reduction of the Pr ions. The lower detection limit for displacements is found to be in the subnanometer range. At 800 °C and an excitation frequency of 1 Hz, the LDV shows a remarkable resolution of 0.3 nm which allows, for example, the characterization of materials with small levels of expansion, such as undoped ceria at high oxygen partial pressure. As the correlation between film expansion and sample bending is obtained through this study, a dimensional change of a free body consisting of the same material can be calculated using the high resolution characteristics of this system. A minimum detectable dimensional change of 5 pm is estimated even under challenging high-temperature conditions at 800 °C opening up opportunities to investigate electro-chemo-mechanical phenomena heretofore impossible to investigate. The expansion data are correlated with previous results on the oxygen nonstoichiometry of PCO thin films, and a defect model for bulk ceria solid solutions is adopted to calculate the cation and anion radii changes in the constrained films during chemical expansion. The constrained films exhibit anisotropic volume expansion with displacements perpendicular to the substrate plane nearly double that of bulk samples. The PCO films used here generate high total displacements of several 100 nm’s with high reproducibility. Consequently, PCO films are identified to be a potential core component of high-temperature actuators. They benefit not only from high displacements at temperatures where most piezoelectric materials no longer operate while exhibiting, low voltage operation and low energy consumption.

scholarly journals Video Environmental Assessment of the Administrative Regions Within Urbgeosystem Territories

2019 ◽  
Keyword(s):  
Housing Stock ◽  
Physiological State ◽  
Video Recording ◽  
Visual Fields ◽  
Urban Ecosystem ◽  
Visual Observation ◽  
Visual Environment ◽  
Visual Elements ◽  
The Brain

Purpose. Assess the visual environment of the Novobavarskiy district within Kharkiv urban ecosystem. Methods. Field-based visual observation, photophixation and video recording, statistical. Results. We used a five-point scale to assess the "attractiveness" of territories and objects regarding the psycho-physiological state of a person to determine the quality of the visual environment of Novobavarskiy district, Kharkiv. As a result of video-environmental studies, it was discovered that there are homogeneous and aggressive fields in the visual environment on the territory of Kharkiv. In most cases the aesthetics of the district architecture has a neutral character, bacause a significant number of buildings does not have a variety of visual elements, so as homogeneous and aggressive areas can be found in great variety. It is determined that in the district there are 36% of comfortable visual fields, 13% are homogeneous and 51% are aggressive visual fields. Recently, there has been positive dynamics in the formation of a comfortable visual environment of the district's housing stock. When building new houses and renovating old buildings, different colours for facades are used. The interior is filled with attractive children's playgrounds and green spaces which transforms the aggressive and homogeneous fields of the visual environment into a comfortable one. Conclusions. The situation shows that it is necessary to create a comfortable visual environment that is not represented sufficiently in this district. In this case, there is a real threat to the physiological functions of the brain regarding the perception of information about the visual environment. And in the future it is also necessary to solve these problems using technologies that have been tested and implemented successfully in European countries.

scholarly journals A Si-Cl geothermobarometer for the reaction zone of high-temperature, basaltic-hosted mid-ocean ridge hydrothermal systems

2009 ◽  
Vol 10 (5) ◽  
pp. n/a-n/a ◽  
Author(s):  
Fabrice J. Fontaine ◽  
William S. D. Wilcock ◽  
Dionysis E. Foustoukos ◽  
David A. Butterfield
Keyword(s):  
High Temperature ◽  
Reaction Zone ◽  
Hydrothermal Systems ◽  
Mid Ocean Ridge ◽  
Ocean Ridge

Video registration of physicochemical processes in BOF cavity at bath top blowing at application oxygen lances of various designs. Report 1. Facility and methodology of the study

2021 ◽  
Vol 77 (8) ◽  
pp. 969-976
Author(s):  
A. G. Chernyatevich ◽  
L. C. Molchanov ◽  
E. N. Sigarev ◽  
S. A. Dudchenko ◽  
V. V. Vakal’chuk ◽  
...  
Keyword(s):  
High Temperature ◽  
Reaction Zone ◽  
Video Camera ◽  
Bath Surface ◽  
Hot Metal ◽  
Metal Melt ◽  
Physicochemical Processes ◽  
Video Registration ◽  
Foamed Slag ◽  
Practical Information

Interaction of the upper oxygen jets with the BOF bath considerably effects the hot metal refining flow. To optimize the lances designs and methods of BOF bath blowing, information is needed on the actual physical and technical phenomena taking place during top blowing of BOF bath by groups of ultrasonic and sonic oxygen jets. It was shown that obtaining the information is possible at high temperature simulation of the BOF bath blowing by application oxygen lances of various designs and video registration. Results of previous studies by filming of the blowing in a BOF and OHF presented. Description of modern facilities of high temperature simulation within a multi-purpose 160 and 60‒80 kg BOFs, equipped by special manholes for observation and registration by video camera the physicochemical processes taking place on the surface of the bath presented. In particular the manholes made it possible to observe the processes taking place at various methods of top and combined blowing of the BOF bath by application regular, two-circuit and double-flow oxygen lances. A methodology of test heats carrying out presented, which ensured obtaining important practical information on forming and variation of dimensions of the reaction zone. In particular, information was obtained about the interaction of ultrasonic and sonic oxygen jets with the metal melt, development of afterburning, emission out of reaction zone C to CO2 in the subsonic and sonic oxygen jets with forming high temperature flares directed on the BOF bath surface or penetrated in the foamed slag, emissions of slag-metal suspension out the BOF, forming of metal-slag sculls on the lance tube during the blowing with various level of foamed slag-metal emulsion.

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