CARLOS ALBERTO DE OLIVEIRA

Projetos de Pesquisa
Unidades Organizacionais
Cargo

Resultados de Busca

Agora exibindo 1 - 10 de 15
  • Artigo IPEN-doc 26370
    Structural integrity analysis of the heavy water reflector tanks of the IPEN/MB-01 Reactor
    2019 - FAINER, GERSON; FALOPPA, ALTAIR A.; OLIVEIRA, CARLOS A. de; JUNQUEIRA, FERNANDO C.; FIGUEIREDO, CAROLINA D.R.; SANTOS, MARCELO M. dos; CARVALHO, DANIEL S.M.; MATTAR NETO, MIGUEL
    The IPEN/MB-01 is a zero power research reactor designed and built by IPEN in partnership with the Brazilian Navy. This reactor is located in IPEN and began operating in 1988. IPEN/MB-01 has been used as an experimental facility for studies on neutron parameters of nuclear reactors moderated by light water. In 2016, a project to modify the core structure of IPEN/MB-01 Reactor was initiated. This project aims the replacement of the rod-type fuel structure for a plate-type one. In order to optimize the performance of the experiments, four tanks filled with D2O were installed around the core. This new core will contain fuel elements that are similar to the ones that will be used in the Brazilian Multipurpose Reactor. In this paper, a complete structural integrity analysis of the four heavy water reflector tanks installed in IPEN/MB-01 Reactor is presented. A numerical analysis was performed applying the finite element method, using ANSYS software and considering ASME Code VIII, division 2.
  • Resumo IPEN-doc 24613
    Ageing assessment of the brazilian research reactor IEA-R1 coresupport structures
    2017 - MARCELINO, S.; OLIVEIRA, C.A.; MATTAR, M.
    IEA-R1 is a research reactor developed by Babcock & Wilcox and operating in IPEN – CNEN/SP since 1957. The core of the reactor is located 7 meters below the swimming pool water level and mounted over eighty holes supporting plate. Over theses holes fuel and control elements, guides, and other structures are located, displaced in a way to optimize experimental arrangements. The main plate is supported by a frame that is connected to an overhead crane through aluminum profiles. This work evaluates the support structure of the core and estimates its service life, taking into account the deformation of the aluminum alloy 6061 T6 due to a critical integrated neutron flux of 0:5 1022 neutrons per cm2. Considering the reactor neutron flux as the main life criteria to the aluminum profiles that support the core structure, we evaluate the remaining working hours of the frame. It also estimates the consequence of a change in the reactor power from 2 MW to 5 MW. Future works should include a visual inspection and an evaluation of the frame materials
  • Resumo IPEN-doc 24609
    Refurbishment of the IEA-R1 primary coolant system piping supports
    2017 - FALOPPA, A.A.; FAINER, G.; OLIVEIRA, C.A.; MATTAR, M.
    This paper presents the study and the structural analysis of the IEA-R1 primary circuit piping supports, considering all the changes involved in the piping system replacement conducted in 2014. The IEA-R1 is a nuclear reactor for research purposes designed by Babcox-Willcox that is operated by IPEN since 1957. The reactor life management and modernization program is being conducted for the last two decades and already resulted in a series of changes, especially on the reactor coolant system. This set of components, divided in primary and secondary circuit, is responsible for the circulation of water into the core to remove heat. In the ageing management program that includes regular inspection, some degradation was observed in the primary piping system. As result, the renewing of the piping system was carried out in 2014. Moreover the poor condition of some original piping supports gave rise to the refurbishment of all piping supports. The aim of the present work is to review the design of the primary system piping supports taking into account the current conditions after the changes and refurbishment.
  • Resumo IPEN-doc 24608
    IEA-R1 renewed primary coolant piping system stress analysis
    2017 - FALOPPA, A.A.; FAINER, G.; OLIVEIRA, C.A.; MATTAR NETO, M.
    A partial replacement of the IEA-R1 piping system was conducted in 2014. The aim of this work is to perform the stress analysis of the renewed primary piping system of the IEA-R1, taking into account the as built conditions and the pipe modifications. The nuclear research reactor IEA-R1 is a pool type reactor designed by Babcox- Willcox, which is operated by IPEN since 1957. The primary coolant system is responsible for removing the residual heat of the Reactor core. As a part of the life management, a regular inspection detected some degradation in the primary piping system. In consequence, part of the piping system was replaced. The partial renewing of the primary piping system did not imply in major piping layout modifications. However, the stress condition of the piping systems had to be reanalyzed. The structural stress analysis of the primary piping systems is now presented and the final results are discussed.
  • Artigo IPEN-doc 24028
    Structural evaluation of IEA-R1 primary system pump nozzles
    2017 - FAINER, GERSON; FALOPPA, ALTAIR A.; OLIVEIRA, CARLOS A. de; MATTAR NETO, MIGUEL
    The IEA-R1 pumps of the primary coolant system may be required to withstand design and operational conditions. IEA-R1 nuclear research reactor is an open pool type reactor operated by IPEN since 1957. The reactor can be operated up to 5MW heating power since it was upgraded in a modernization program conducted by IPEN. The primary coolant system is composed by the piping system, decay tank, two heat pumps and two heat exchangers. In the latest arrangement upgrade of the primary system, conducted in 2014 as part of an aging management program, a partial replacement of the coolant piping and total replacement of piping and pump supports were done. As consequence, reviewed loads in the pump nozzles were obtained demanding a new evaluation of them. The aim of this report is to present the structural evaluation of the pump nozzles, considering the new loads coming from the new piping layout, according to: API 610 code verification, Supplier loads and structural analysis applying finite element method, by using the ANSYS computer program, regarding ASME VIII Div 1 & 2 recommendations.
  • Artigo IPEN-doc 22849
    Avaliação estrutural de um suporte da tubulação do sistema de refrigeração do reator nuclear de pesquisa IPEN IEA-R1
    2016 - FALOPPA, ALTAIR A.; FAINER, GERSON; OLIVEIRA, CARLOS A. de; MATTAR NETO, MIGUEL
    Este trabalho apresenta a avaliação estrutural de um suporte da tubulação do Circuito Primário do reator nuclear de pesquisa do Instituto de Pesquisas Energéticas e Nucleares - IPEN. O reator IEA-R1 é um reator nuclear de pesquisa projetado pela Babcox-Wilcox que opera no IPEN desde 1957. Um programa de modernização tem sido conduzido nos últimos 25 anos, e uma série de modificações foram implementadas, especialmente no sistema de refrigeração do reator. Entre as modificações mais recentes está a troca de componentes do sistema de refrigeração, tais como: bombas, trocadores de calor e tubulação, além da reforma dos sistemas de tratamento e re-tratamento de água. Este conjunto de equipamentos, divididos em sistema primário e secundário, é responsável pela circulação da água no núcleo do reator para a retirada de calor gerado pela fissões nucleares do U-235. A substituição parcial da tubulação do Circuito Primário do reator IEA-R1, realizada em 2014, resultou em alterações nos suportes existentes e no desenvolvimento de um novo tipo de suporte para a tubulação. O objetivo deste trabalho é apresentar o modelo de cálculo aplicado à avaliação estrutural deste novo suporte sob as diversas condições de carregamentos aplicáveis.
  • Artigo IPEN-doc 21009
    IEA-R1 renewed primary coolant piping system stress analysis
    2015 - FAINER, GERSON; FALOPPA, ALTAIR A.; OLIVEIRA, CARLOS A. de; MATTAR NETO, MIGUEL
  • Artigo IPEN-doc 21008
    Refurbishment of the IEA-R1 primary coolant system piping supports
    2015 - FAINER, GERSON; FALOPPA, ALTAIR A.; OLIVEIRA, CARLOS A. de; MATTAR NETO, MIGUEL
  • Artigo IPEN-doc 05873
    Stress analyses of the internals of a research PWR vessel. A general overview
    1995 - MIRANDA, C.A.J.; MATTAR NETO, M.; OLIVEIRA, C.A.; CRUZ, J.R.B.; ASSIS, G.M.V.; ALBUQUERQUE, L.B.
  • Artigo IPEN-doc 05874
    Stress analysis of a research PWR pressure vessel. A general description
    1995 - MIRANDA, C.A.J.; MATTAR NETO, M.; OLIVEIRA, C.A.; CRUZ, J.R.B.; BEZERRA, L.M.; ALBUQUERQUE, L.B.; ASSIS, G.M.V.