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Virtual reality 3D stereo technology to improve motivation in the learning process of use of nuclear energy in eletric power generation
No full textVirtual Environments (VE) are computer-generated environments. The advantage of VE is that people can be
immersed by the simulated environment, which would sometimes be unavailable due to cost, safety, or
perceptual restrictions in the real environment. In this work, Virtual Reality 3D Stereo technology is used to
disseminate the application of nuclear energy in electric power generation. Virtual Reality with 3D Stereo
Vision has a significant effect on people to retain what they have learned, and is clearly superior to traditional
learning techniques, such as 2D videos and books, since navigation in 3D virtual worlds can improve
motivation in the learning process. In this way the main systems of a PWR nuclear power plant had been
implemented virtually in 3D stereo technology. As a result, it is expected that learning be achieved in a clearer,
joyful and more objective way
Evaluation of oil/water separators units in industrial effluents using radioactive tracers
No full textIn this work a methodology to study and evaluate oil/water separators with radioactive tracers is presented.
These units make possible to remove residues of organic phase present in the effluent and allow to reusing the
water in other operations. As radioactive tracers we use 182 Br for the aqueous phase and 123 I for organic phase and two radioactive detectors ( NaI 2x2”) register the displacement of the tracers in the unit. With this
methodology was possible to analyze the response of the unit in various experimental situations and identify
problems in its operation, which interfere in the final quality of the effluent treatment
Absence of Diquarks in S-Wave Baryons
No full textWe analyze the dynamics of diquark formation in baryons containing one light and two heavy quarks. Due to the slower motion of the heavy quarks, we consider the motion of the light quark in a reference frame fixed in the two heavy ones. The potential of the light quark interacting with the two heavy quarks is derived from the quark–antiquark potential in mesons. This potential has a repulsive barrier between the two heavy quarks. A variational approach similar to that used in the study of the hydrogen molecule is applied to determine the two lowest energy eigenvalues and eigenfunctions of the light quark. The time-dependent wave function obtained describes the oscillation of the light quark along the direction defined by the two heavy quarks. We observe that the energy of this oscillating state is higher than the repulsive barrier between the two heavy quarks. There is no tunneling in the oscillation of the light quark, so we conclude that there is not formation of clusters or metastable states of a heavy and a light quark in this kind of baryons
User centered design of a digital procedure guidance component for nuclear power plant operation
No full textThe use of nuclear power plants to produce electric energy is a safety-critical process where ultimate
operational decisions still relies with the control room operators. Thus it is important to provide the best
possible decision support through effective supervisory control interfaces. A user centered design approach,
based on cognitive task analysis methods, was used to observe the operators training on the nuclear power plant simulator of the Human System Interface Laboratory (LABIHS). We noted deficiencies in the integration
between the computerized interfaces and the hardcopy (paper) procedures. An new prototype of digital
procedures – the digital procedure component guidance (PCG) – was designed in PowerPoint as an alternative
to the current hardcopy procedure manuals. The design improves upon the graphical layout of system
information and provides better integration of procedures, automation, and alarm systems. The design was
validated by expert opinion and a scenario-based comparison. Future implementation and testing of the redesign is suggested for further validation
Virtual reality technology as a tool for human factors requirements evaluation in design of the nuclear reactors control desks
No full textThe Virtual Reality (VR) in an advanced computer interface technology that allows the user to Interact or to explore a three-dimensional environment through the computer, as was part of the virtual world. This technology presents great applicability in the most diverse areas of nuclear reactors control desks. Moreover, this paper presents a case study: a virtual model of the control desk, developed using Virtual Reality Laboratory at IEN, and understands the stereo visualization of the Argonauta research nuclear reactor control desk for a static ergonomic evaluation using check-lists, in accordance to the standards and human factors nuclear international guides (IEC 1771, NUREG-0700)
The use of agents and multi-agents for accident analysis in pressurized water reactor
No full textFrom the viewpoint of the operator of a Nuclear Power Plant (NPP) it is very important the perspective of anticipation of the identification of accidents, either Design Basic Accidents (DBAs), Transient Accidents or those that can be lead to catastrophic consequences, as in the case of Severe Accidents that involve the melting of the core. The objective of this work is to discuss the development an of prototype system that can offer the operator the possibility to bring the operation of the NPP to a safe condition before the occurrence of an undesirable accident. For such, the concept of single-agents and multi-agents will be used to (1) formulate an environment to consolidate and manage the knowledge generated from a database. Fuzzy logic will be used to represent the knowledge stored in the database (DB). Inference mechanisms will be created to implement cognitive agents that manipulate the knowledge represented in this model. In a second stage, the concept of single-agents and multi-agents will be used (2) to acquire safety functions in real time and design variables for anticipatory analysis, so as to decide in the present based on information of the future. And, finally, (3) the concept will be used for the development of an intelligent system of diagnosis
Ultrassonic stress measurements in a carbon steel neam under bending
No full textBending stresses occur frequently in nuclear pressure vessels walls and internals and must be accounted for
when assessing their structural integrity. As a first step toward estimating the accuracy of ultrasonic
measurements of the magnitude and direction of the principal stresses in metallic vessels under bending, the
acoustic birefringence technique was employed in this work to determine the in-plane bending stresses in a
simply supported carbon steel beam subjected to a locally distributed load. The experimentally determined
stresses were compared with analytical values computed from the theory of strength of materials. Normal
incident ultrasonic shear waves were employed and the fractional difference of the time of flight measurements
in two orthogonal directions at the same point - the birefringence ratio - was determined. The ultrasonic waves
were generated, acquired and digitalized by an especially developed ultrasonic system, and their times of flight
calculated using mathematical processing. Selected regions of the beam were examined ultrasonically, before
and during the mechanical loading. The comparison of the analytical and experimental results indicated that the
ultrasonic birefringence technique can be useful in determining the magnitude and direction of the principal
stresses in beams subjected to in-plane bending
On the application of sirer-ADS in the simulation of transients in accelerator driven system (ADS)
No full textAn innovative reactor proposed to be used as an incinerator of Minor Actinides (MAs) like Np, Am and Cm is
in progress. This technology, named Accelerator Driven System (ADS), consists in a subcritical core, having a
central region where there is a target, as Lead-Bismuth Eutectic (LBE), which suffers collisions with a proton
beam from an accelerator. The collisions produce neutrons depending of the proton energies. These fast neutrons produce fissions in the fuel and some of them are captured at the blanket, which surrounds the fuel region, for transmuting the transuranic elements (TRUs). Apparently this reactor is intrinsically safe, as compared with thermal ones, but the control of the reactor is based on the proton beam, which does not depend on intrinsic or internal control rod. Even so, in the scope of the development of ADS, benchmark problems have been proposed by Nuclear Energy Agency (NEA) to analyze some transients that may occur due to variation in the current of the accelerator as well as perturbation in the subcritical core. In this paper it is shown the application of SIRERADS code on one of the benchmarks. In our application we identified an error on the wetted perimeter for the channel, as specified in the benchmark. Of course that leads different results. Because of that, some extra calculations are made to validate SIRER-ADS showing good agreement with the analytical solution. Calculations with the correct perimeter and the benchmark one are shown. In both cases SIRER-ADS exhibits consistent results
On Brazil’s participation in the international project on inovative nuclear reactors and fuel cycles (INPRO)
No full textIn response to a resolution of its 44th General Conference (GC(44)/RES/21) held in September 2000, the
International Atomic Energy Agency launched in May 2001 the International Project on Innovative Nuclear
Reactors and Fuels Cycles (INPRO) with the objective of supporting the safe, sustainable, economic and
proliferation-resistant use of nuclear technology to meet the global energy needs of the 21st century. Brazil
joined the project from its beginnings and in 2005 submitted a proposal for the screening assessment using
INPRO methodology of two small-size light-water reactors as potential components of an innovative nuclear
reactor system (INS) completed with a conventional open nuclear fuel cycle. The INS reactor components
currently being assessed are the International Reactor Innovative and Secure (IRIS) that is being developed by
an international consortium made of 21 organizations from 10 countries (Brazil included) led by the
Westinghouse Company, and the Fixed Bed Nuclear Reactor (FBNR) that is being developed at the Federal
University of Rio Grande do Sul. This paper gives an overview of Brazil’s participation in INPRO, highlighting
the objective, scope and intermediate results of the assessment study being performed, and the possibilities for
participation in one or two collaborative research projects under INPRO Phase 2 Action Plan for 2008-2009
Volume fraction calculation in multiphase system such as oil-water-gas using neutron
Get PDFMulti-phase flows are common in diverse industrial sectors and the attainment of the volume fraction of each
element that composes the flow system presents difficulties for the engineering process, therefore, to determine them is very important. In this work is presented methodology for determination of volume fractions in annular three-phase flow systems, such as oil-water-gas, based on the use of nuclear techniques and artificial intelligence. Using the principle of the fast-neutron transmission/scattering, come from an isotopic 241Am-Be source, and two point detectors, is gotten measured that they are influenced by the variations of the volumec fractions of each phase present in the flow. An artificial neural network is trained to correlate such measures with the respective volume fractions. In order to get the data for training of the artificial neural network without necessity to carry through experiments, MCNP-X code is used, that simulates computational of the neutrons transport. The methodology is sufficiently advantageous, therefore, allows to develop a measurement system capable to determine the fractions of the phases (oil-water-gas), with proper requirements of each petroliferous installation and with national technology contributing, possibly, with reduction of costs and increase of productivity