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Mesa de controle virtual para treinamento de operações: um estudo de caso para um simulador de usina nuclear
Get PDFNuclear Power Plant (NPP) is a facility for electrical energy generation. Because of its high degree of complexity and very rigid norms of security it is extremely necessary that operators are very well trained for the NPP operation. A mistaken operation by a human operator may cause a shutdown of the NPP, incurring in a huge economical damage for the owner and for the population in the case of a electric net black out. To reduce the possibility of a mistaken operation, the NPP usually have a full scope simulator of the plant´s control room, which is the physical copy of the original control room. The control of this simulator is a computer program that can generate the equal functioning of the normal one or some scenarios of accidents to train the operators in many abnormal conditions of the plant. A physical copy of the control room has a high cost for its construction, not only of its facilities but also for its physical components.
The proposal of this work is to present a project of a virtual simulator with the modeling in 3D stereo of a control room of a given nuclear plant with the same operation functions of the original simulator. This virtual simulator will have a lower cost and serves for pretraining of operators with the intention of making them familiar to the original control room.Uma usina nuclear é uma instalação de geração de energia elétrica. Devido ao seu alto grau de complexidade e normas rígidas de segurança é extremamente necessário que seus operadores sejam muito bem treinados para a sua operação, pois caso haja uma falha humana, esta irá acarretar um desligamento da planta com conseqüentes prejuízos econômicos para a operadora e para a população em geral, devido a possibilidade de um black out na rede elétrica. Para evitar essa possibilidade de falha a operadora, normalmente, possui um simulador full scope da mesa de controle da planta, que é a réplica física da mesa de controle original. O controle deste simulador é um programa de computador que pode gerar o funcionamento igual ao normal ou vários cenários de acidentes para treinarem os seus operadores nas varias condições de operação da planta. Devido ao simulador ser a réplica física da mesa de controle, acarreta um custo muito elevado para a construção das instalações prediais e dos componentes da mesa. A proposta deste trabalho é apresentar um projeto de um simulador virtual com a modelagem em 3D estéreo da mesa de controle da planta nuclear e com as mesmas funções de operação do simulador original. Este simulador virtual terá um custo muito menor e serve para um pré-treinamento de operadores com o intuito de se familiarizar com o original
Using virtual reality in the training of security staff and evaluation of physical protection barriers in nuclear facilities
Get PDFThe physical security of facilities containing radioactive objects, an already important matter, now has a new
aggravating factor: the existence of groups intending to obtain radioactive materials for the purpose of
intentionally induce radioactive contamination incidents, as for example the explosion of dirty bombs in
populated regions, damaging both people and environment. In this context, the physical security of such
facilities must be reinforced so to reduce the possibilities of such incidents. This paper presents a adapted game engine used as a virtual reality system, enabling the modeling and simulation of scenarios of nuclear facilities containing radioactive objects. In these scenarios, the physical protection barriers, as fences and walls, are simulated along with vigilance screens. Using a computer network, several users can participate simultaneously in the simulation, being represented by avatars. Users can play the roles of both invaders and security staff. The invaders have as objective to surpass the facility’s physical protection barriers to steal radioactive objects and flee. The security staff have as objective to prevent and stop the theft of radioactive objects from the facility. The system can be used to analysis simulated scenarios and train vigilance/security staff. A test scenario was already developed and used, and the preliminary tests had satisfactory results, as they enabled the evaluation of the physical protection barriers of the virtual facility, and the training of those who participated in the simulations in the functions of a security staff
A stabilized finite element formulation for the solution of the Navier-Stokes equations in axyssimetric geometry
Get PDFThe aim of this paper is to solve axysssimetric problems found in nuclear reactors engineering. Thus, a
stabilized finite element formulation for the solution of the Navier-Stokes and energy equations for axyssimetric
problems has been developed and tested. This formulation has been implemented in the NS_SOLVER_MPI_2D_A program developed at the Parallel Computation Laboratory of the Instituto de Engenharia Nuclear (LCP/IEN) and is now available either for safety analysis or design of nuclear systems.
The results show the simulation of the mixed convection phenomena that occurs in the downcomer of a PWR
nuclear reactor
Methodology for Labeling Oil Products with 123I
Get PDFThe objective was the development a methodology to label organic compounds with radioactive iodine (123I) from the reaction of organic compound with iodine nomochloride (ICL). The process begins with the production of 123ICl from the oxidation of potassium iodate in acid medium. The ICL labeled with 123I is extracted from aqueous phase using diethyl ether and then mixed with the organic compound to be labeled and the process is based on adding the radioactive iodine to the Carbon-Carbon double bonds of the organic compound. To measure the efficiency of the labeling process, in all stages samples were collected and the total activity of 123I was measure. The results show a production yield of 82% for lubricant oil and 85% for gasoline and diesel
Production of Gaseous Tracer I2 from the Sodiumiodide Salt
Get PDFFound in the nature in form different, the iodine has been used in diverse works in the area of the industry and health. The iodine is very unstable and volatile in the ambient temperature and the I2 is one of the diverse gaseous forms found. In this work was developed methodology for production of gaseous tracer from the sodium iodide (NaI) 0,1 M marked with 123I. The synthesis was processed with in chlorine acid (HCl) 1M and sodium iodate salt (NaIO3). The production of gas I2 initially was carried through in unit of glass with the inert material and the purpose was to study the kinetic of reaction. The synthesis occurs in the reaction bottle and the produced gas is stored in the collect bottle that contains a starch solution (5 g/100 mL water). To determine the efficiency of production of gas I2, analytic tests had been carried through, where the consumption of iodide ions of the bottle of reaction is measured. The optimization of production of the gaseous tracer was studied varying parameters as: concentration of iodide and iodate, concentration of acid and temperature. Then, the synthesis of the radiotracer was realized in the compact unit, being utilized as main reagent the salt radiated of sodium iodide, Na123I. The transportation of elementary iodine was studied by a scintillation detector NaI (2 x 2)” placed in the reaction bottle. To acquire the data, the detector use a set of electronic modules for the acquisition of signals generated
The Influence of Limited Kinematic Hardening in Shakedown Analysis
Get PDFThe use of the Design by Analysis concept is a trend in modern pressure vessel and piping calculations.
DBA flexibility allow us to deal with unexpected configurations detected at in-service inspections. It is
also important, in life extension calculations, when deviations of the original standard hypotesis adopted
initially in Design by Formula, can happen. To apply the DBA to structures under variable mechanic
and thermal loads, it is necessary that, alternate plasticity and incremental collapse (with instantaneous
plastic collapse as a particular case), be precluded. These are two basic failure modes considered by
ASME or European Standards in DBA. The shakedown theory is the tool available to achieve this
goal. In order to apply it, is necessary only the range of the variable loads and the material properties.
Precise, robust and efficient algorithms to solve the very large nonlinear optimization problems generated
in numerical applications of the shakedown theory is a recent achievement. Zouain and co-workers
developed one of these algorithms for elastic ideally-plastic materials. But, it is necessary to consider
more realistic material properties in real practical applications. This paper shows an enhancement of
this algorithm to dealing with limited kinematic hardening, a typical property of the usual steels. This
is done using internal thermodynamic variables. A discrete algorithm is obtained using a plane stress,
mixed finite element, with internal variable. An example, a beam encased in an end, under constant
axial force and variable moment is presented to show the importance of considering the limited kinematic
hardening in a shakedown analysis
A modal multidimensional kinetics method using pseudo-harmonics
Get PDFThis work proposes to use the pseudo-harmonics technique as a modal method in spatial kinetics. The
pseudo-harmonics are the eigenfunctions associated with the leakage + removal operators in the multigroup
steady-state diffusion equation. In this work, the pseudo-harmonics are obtained from the diffusion equation discretized with the Coarse Mesh Finite Difference Method (CMFD) coupled to the Nodal Expansion Method (NEM). Modal methods approximate the time-dependent flux by expanding it in predetermined functions
which represent the space dependence, so that the unknowns are the expansion coefficients, which carry
all time dependence of the problem. To obtain the system of equations whose solutions are the modal
expansion coefficients, use is made of a weighting function procedure. This process leads to a linear system
of ordinary differential equations whose dimension equals the number of pseudo-harmonics employed. The solution of these equations is obtained through analytical integration of the delayed neutrons precursor equations, while the time dependence of the neutrons flux is treated by the Rosenbrock Generalized Runge-Kutta method with automatic time step size control. A direct method was developed from the spatial kinetics equations discretized by CMFD coupled to NEM in order to compare the methods. The proposed modal method was tested for the case of an operational transient and for the case of a transient with scram, and presented good results, when compared with this direct method
Medida de tamanho de poro em membrana polimérica de microfiltração utilizando técnica ultrassônica e redes neurais artificiais
No full textO presente trabalho propõe um estudo sobre a avaliação por ultrassom do
tamanho de poro em membranas poliméricas de microfiltração, utilizadas na área
nuclear para a filtração de rejeitos radioativos, no tratamento de águas residuais da
indústria petroquímica, na indústria eletrônica para a produção de água ultrapura
para a fabricação de condutores e para lavagem de microcircuitos e em muitos
outros processos de separação. Existem diversos processos para medidas de
tamanhos de poros em membranas, dentre estes, microscopia eletrônica, ponto de
bolha e porosimetria por intrusão de mercúrio, porém a maioria destes utiliza
técnicas destrutivas, de custo elevado ou de grande tempo de análise. A proposta
deste trabalho é medir tamanho de poro utilizando técnica ultrassônica no domínio
da frequência e redes neurais artificiais. Foi utilizado um gerador/receptor de pulsos
ultrassônicos, um transdutor de 25 MHz, um tanque de imersão e membranas
microporosas de tamanhos de poros 0,2 μm, 0,4 μm, 0,6 μm, 8 μm, 10 μm e 12 μm.
Os sinais ultrassônicos após percorrerem a membrana, voltam ao transdutor
(emissor/receptor) trazendo informações da interação do sinal com as membranas.
Estes sinais foram utilizados para o treinamento de redes neurais, e estas
forneceram a precisão necessária para a distinção dos mesmos. Logo após, foi feita
a comparação desta técnica com a de microscopia eletrônica de varredura. O
experimento mostrou resultados muito próximos aos resultados obtidos com o MEV,
o que indicou que a técnica estudada pode medir tamanho de poro em membrana polimérica com boa precisão e repetibilidade. Por ser uma técnica não destrutiva poder ser usada em linha de produção.This work presents a study of the pore size in microfiltration polymeric
membranes, used in the nuclear area for the filtration of radioactive liquid effluent, in
the residual water treatment of the petrochemical industry, in the electronic industry
for the ultrapure water production for the manufacture of conductors and laudering of
microcircuits and in many other processes of separation. Diverse processes for
measures of pores sizes in membranes exist, amongst these, electronic microscopy,
of bubble point and mercury intrusion porosimetry, however the majority of these
uses destructive techniques, of high cost or great time of analysis. The proposal of
this work is to measure so great of pore being used ultrasonic technique in the time
domain of the frequency and artificial neural networks. A receiving/generator of
ultrasonic pulses, a immersion transducer of 25 MHz was used, a tank of immersion
and microporous membranes of pores sizes of 0,2 μm, 0,4 μm, 0,6 μm, 8 μm, 10 μm
and 12 μm. The ultrasonic signals after to cover the membrane, come back to the
transducer (emitting/receiving) bringing information of the interaction of the signal
with the membranes. These signals had been used for the training of neural
networks, and these had supplied the necessary precision the distinction of the same
ones. Soon after, technique with the one of electronic microscopy of sweepings was
made the comparison of this. The experiment showed very resulted next to the
results gotten with the MEV, what it indicated that the studied technique is ideal for
measure of pore size in membranes for being not destructive and of this form to be
able to be used also on-line of production
Realidade virtual como ferramenta motivadora ao processo de aprendizado
Get PDFEste trabalho reporta os resultados do desenvolvimento de aplicações computacionais utilizando técnicas de
realidade virtual, para fins de ensino e divulgação científica. O objetivo é desenvolver aplicações que possam
facilitar o aprendizado, com o uso de recursos computacionais que o tornem uma atividade lúdica e mais
agradável para os alunos, de forma a melhorar o envolvimento destes com os temas abordados, para que os
conhecimentos possam ser melhor absorvidos. São mostrados os resultados das aplicações desenvolvidas, com as perspectivas de sua utilização através de apresentações em laboratórios das duas Instituições envolvidas