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CONSTRUÇÃO DE INTERFACES PARA SALAS DE CONTROLE AVANÇADAS DE PLANTAS INDUSTRIAIS
No full textAs interfaces homem-sistema (IHSs) são as partes importantes de uma planta industrial na qual as
pessoas interagem para realizar suas funções e tarefas. As IHSs incluem alarmes, mostradores de
informação e controles. Uma das linhas de pesquisa do Laboratório de Interfaces Homem-Sistema
(LABIHS) é o desenvolvimento e avaliação de interfaces para salas de controle de plantas industriais.
Este artigo apresenta de maneira sucinta o estado da arte das interfaces homem-sistema, com
ênfase para a descrição das três principais filosofias de construção de interfaces de operação:
interfaces orientadas a tarefa, interfaces ecológicas e interfaces orientadas a função. O artigo
também apresenta uma descrição dos principais componentes de hardware e software do LABIHS,
com ênfase para as ferramentas de desenvolvimento e avaliação de interfaces deste laboratório. Ao
final do artigo é apresentada, como exemplo, uma nova tela de visão geral da planta simulada que foi
construída com base na filosofia orientada a tarefa. A nova tela de visão geral da planta foi avaliada
no simulador nuclear do LABIHS usando o procedimento E-0, que faz parte dos procedimentos de
operação em emergência (POEs) da planta nuclear. Os resultados obtidos mostraram que a nova
tela de visão geral da planta apresenta um aumento substancial na quantidade de informação sobre
o estado geral da planta para os operadores quando comparada com a tela de visão geral anterior
Full Scope Simulator Of A Nuclear Power Plant Control Room Using 3d Stereo Virtual Reality Techniques For Operators Training
No full textPractical training of nuclear power plants operators are partially performed by means of simulators. Usually
these simulators are physical copies of the original control room, needing a large space on a facility being also
very expensive. In this way, the proposal of this paper is to implement the use of Virtual Reality techniques to
design a full scope control room simulator, in a manner to reduce costs and physical space usage
Employment of the Technique of Radiotracers for Analysis of Industrial Filters
Get PDFThe main aim of this work is to develop a methodology to evaluate the characteristics of porous media in filter using the radio-tracing technique. To do this, an experimental prototype filter made up of an acrylic cylinder, vertically mounted and supported on the lower side by a controlled leaking valve was developed. Two filters (spheres of acrylic and silica crystals) were used to check the movement of the water through the porous media using 123I in its MIBG (iodine-123-meta-iodo benzyl-guanidine) form. Further up the filter an instantaneous injection of the substance makes it possible to see the passage of radioactive clouds through the two scintillatory detectors NaI (2x2)” positioned before and immediately after the cylinder with the filtering element (porous media). The are caused by the detectors on the passage of the radioactive cloud are analyzed through statistical functions using the weighted moment method which makes it possible to calculate the Residence-Time (the amount of time the tracer takes to thoroughly pass through the filter) per the equation of dispersion in tubular flow and the one-directional flow of the radiotracer in the porous media
experimental investigation of attenuation of ultrassonic field in a circular pipe by a spherical body
No full textUltrasonic techniques are low cost and non intrusive for two-phase flow measurements, especially for applications in nuclear power plants, petrochemical plants and industrial plants. Ultrasonic transducers of different frequencies and sizes generate different ultrasonic fields in different pipe diameters. The objective of this work is to study experimentally the influence, in the ultrasonic signal, of a steel sphere, that simulates a discontinuity like an air bubble, immerse in a vertical water column. It was applied the pulse-echo ultrasonic technique and it was investigated the influence of the steel sphere in the ultrasonic signal amplitude – from the sphere and from the back wall. A stainless steel AISI 316 pipe in vertical position of 2 mm thickness and 53 mm internal diameter was used. The steel spheres were of diameters 3/16” and 5/16”. A transducer of 10 MHz frequency / ¼” diameter and another of 5 MHz frequency / ½”diameter were used to evaluate the influence of the spheres in the ultrasonic field. The experimental results show that the frequency influences the transducer sensitivity
The analytical benchmark solution of a spatial diffusion kinetics in source driven systems for homogeneous media
No full textThis paper describes a closed form solution obtained by the expansion method for the general time dependent diffusion model with delayed emission for source transients in homogeneous media. In particular, starting from simple models, and increasing the complexity, numerical results were obtained for different types of source transients. Thus, first an analytical solution of the one group without precursors was solved, followed by considering one precursors family. The general case of G-groups with R families of precursor although having a closed form solution, cannot be solved analytically, since there are no explicit formulae for the eigenvalues, and numerical methods must be used to solve such problem. To illustrate the general solution, the multi-group (three groups) time-dependent without precursors was also solved and the results inter compared with results obtained by the previous one group models for a given fast homogeneous media, and different types of source transients. The results are being compared with the obtained by numerical methods
Eletro-oxidative leaching of pitchblende minerals for uranium extration and determination by spectrophotometry in flow injection analysis system
No full textA method for uranium extraction from pitchblende minerals samples by electro-oxidative leaching was developed. An electro-dissolution cell associated to an on line sampler system was designed and tested in order to evaluate the influence of current density, leaching time, temperature and the nature and concentration of the electrolyte on the electro-oxidative leaching process. The flow analysis system used in the uranium determination yielded analytical curves with a linear behavior (r= 0.999) in the concentration range of 0.05 to 2.0 mg L-1, a relative standard deviation of 5.5% (at 0.1 mg L-1), a detection limit of 0.02 mg L-1 and analytical throughput of 60 determination per hour. The results obtained by the developed methodology for the uranium electro-oxidative extraction from pitchblende minerals samples showed a good agreement (r= 0.999) up to 98% were achieved for one minute leaching time, with a good reproducibility. The electro-oxidative extraction system showed advantages in relation to the conventional technique, such as: possibility of automation of all analytical process, use of lower sample amounts, more swiftness in the uranium extraction and use of lower amounts of acids
TLD environmental monitoring: an interlaboratorial comparison
No full textSince 2000, the Thermoluminescent Dosimetry Laboratory of the Instituto de Engenharia Nuclear (LDOS/IEN)
measures the environmental, indoor and outdoor air kerma rate at IEN facilities. It uses Harshaw LiF:Mg,Cu,P
thermoluminescent detectors (TLD-100H) chips. In order to evaluate its performance, the LDOS/IEN promoted in 2006 a comparison study with the environmental dosimetry system of the Thermoluminescent Dosimetry
Laboratory of the Instituto de Radioproteção e Dosimetria (LDT/IRD). LDT/IRD has more than 30 years
experience with environmental TLD measurements. It also participates, since 1977, in the International
Intercomparison of Environmental Dosemeters sponsored by the United States Department of Energy (DOE), with good results. In this study, both LDOS/IEN and LDT/IRD environmental dosimeters were placed together on seven different points of IEN facilities and stay there for two months. At the end of this period, the dosimeters were withdrawn and sent to their respective TLD laboratories to be evaluated following their routine procedures. The results indicated that both laboratories were quite in agreement with a correlation factor of about 0.99
Radon measurements in the environmental monitoring programme at Nuclear Engineering Institute
No full textThe Nuclear Engineering Institute (IEN), situated in Cidade Universitária Island, has particle accelerator CV 28, a particle accelerator RDS-111. Research nuclear reactor Argonauta, a radioactive waste repository, besides chemical laboratories which carry out activities with radioactive materials. Due to the developed works, solid wastes, liquid effluents, gases and aerosols can be produced and released to the environment and the set of these facilities sign the source term. Taking into account the atmospheric way as the most critical exposure way for population, especially the critical group, radon levels, aerosols and gamma exposure must be monitored. Within this context, one of the objectives of the Environmental Monitoring Programme is to keep an ongoing record of radioactivity levels in institute environment, to detect eventual material release that would need corrective actions. Radon Laboratory in IEN has periodically carried out measurements of 222 Rn levels, a radioactive gas from 238U chain, within institute area in six points regarded as relevant for detection of material release. Along time the radon, has been measured, its levels has been kept within normal environmental levels, with no indication of accidental release
Detection of drugs and plastic explosives using neutron tomography
No full textThe unique ability of neutrons to image certain elements and isotopes that are either completely undetectable or poorly detected by other Non-Destructive-Assay (NDA) methods makes neutron radiography animportant tool for the NDA community. Neutron radiography, like other imaging techniques takes a number of different forms (i.e. / that is film, radioscopic, transfer methods, tomography, etc.) In this work report the Neutron Tomography System developed, which will allow inspections NDA of samples with high efficiency, in terms of minors measure time and the result analysis, and the application for detection of drugs and plastic explosives, which is very important for the combat to the terrorism and drug trafficking. The neutron tomography system developed is 3rt/ third generation. Therefore a rotary table driven by a step motor connected to a computerized motion control system has been installed at the sample position. In parallel to this a suitable electronic imaging device has been designed and can be controlled by a computer in order to synchronize the software the detector and of the rotary table with the aim of an automation of measurements. To obtain 2D tomography image, a system with an electronic imaging system for producing real time neutron radiography. Images are processing digital for cancel random noise effects and to optimize spatial resolution. Finally, using a (ARIEN) algorithm reconstruction of tomography images by finite element maximum entropy. The system was installed adjacent to the exit of the J-9 irradiation channel of the Argonauta Reactor in the Nuclear Engineering Institute (IEN) – which is an organ of the National Nuclear Energy Commission (CNEN - Brazil).The Argonauta reactor operates at 340 watts, being that the characteristics of the neutron beam on the plane of the image: thermal neutron flux n cm s 5 2 4,46 ×10 /. In the tomography assays, several encapsulated samples of paste, rock and cocaine powder and plastic explosives devices