DELVONEI ALVES DE ANDRADE

Resumo

Possui graduação em Engenharia Mecânica pela Universidade Federal de Uberlândia (1983), mestrado em Engenharia Aeronáutica e Mecânica pelo Instituto Tecnológico de Aeronáutica (1987) e doutorado em Tecnologia Nuclear pela Universidade de São Paulo (1999). Atualmente é tecnologista sênior da Comissão Nacional de Energia Nuclear, professor da Universidade de São Paulo. Tem experiência na área de Engenharia Nuclear, com ênfase em Engenharia Nuclear, atuando principalmente nos seguintes temas: Tecnologia de reatores, Dinâmica dos Fluidos Computacional (CFD), Modelagem Numérica, Análise de acidentes, RELAP, Termo-Hidráulica, Circulação Natural, Ultracentrifugação, Fatores Humanos aplicados à Tecnologia Nuclear e Modelo instrumental para implementação de processo gerencial. Recentemente tem se dedicado ao estudo de modelos de turbulência em circuitos de circulação natural. Membro eleito da Comissão de Pós-Graduação do Programa de Tecnologia Nuclear IPEN/USP nos períodos 2009-2011 e 2011-2013. Coordenador do programa PAE de 2011-2021. Vice-presidente do programa de mestrado e doutorado em Tecnologia Nuclear da USP, 2011-2012. Presidente do programa de mestrado e doutorado em Tecnologia Nuclear da USP de 2013-2021. Membro do Conselho de Pós-Graduação (CoPGr) da USP, da Câmara de Normas e Recursos (CaN) 2011-2021. É membro da International Nuclear Security Education Network (INSEN) na Agência Internacional de Energia Atômica (IAEA) em Viena, Áustria e do World International Nuclear Security (WINS) também em Viena, Áustria. (Texto extraído do Currículo Lattes em 08 out. 2021)

Projetos de Pesquisa
Unidades Organizacionais
Cargo

Resultados de Busca

Agora exibindo 1 - 10 de 221
  • Artigo IPEN-doc 30496
    O impacto da Anomia sobre servidores quando normas/regras não são comunicadas de forma clara, em um Instituto de Pesquisas
    2024 - GIMENES, CELSO H.; GIMENES, ALINE da S.; ANDRADE, DELVONEI A. de; BIDO, DIOGENES de S.
    A anomia organizacional é um fenômeno que se refere à percepção dos empregados de que a organização não possui normas, valores claros e efetivos, o que dificulta o desenvolvimento profissional. Com o objetivo de investigar o clima anômico percebido pelos servidores, esta pesquisa analisou a discrepância entre as normas ‘e valores publicados pela instituição e o comportamento adotado pelos indivíduos ou pequenos grupos no dia a dia. O estudo contou com a participação de 267 servidores de uma instituição de pesquisa na cidade de São Paulo, que responderam à Escala de Anomia desenvolvida por Souza, M.A. e Junior, R. de C. Ribas (2013), bem como forneceram informações sociodemográficas. A análise estatística demonstrou que os instrumentos utilizados foram confiáveis e fidedignos. Os resultados indicaram uma influência negativa da anomia real sobre a anomia publicada.
  • Artigo IPEN-doc 30460
    Measurement of the heat power generated by decay of fission products in fuel assemblies of the IEA-R1 research reactor
    2024 - PRADO, ADELK C.; TERREMOTO, LUIS A.A.; UMBEHAUN, PEDRO E.; ANDRADE, DELVONEI A.
    Fuel assemblies of the IEA-R1 research reactor were probed in calorimetric experiments. A special calorimeter was commissioned for that purpose. A theoretical model was proposed for the calorimeter. The fuel assemblies EC214, EC210 and EC207 were probed with cooling times ranging from 22 hours to 1043 days and declared U235 burnup ratios ranging from 36 % to 45 %. Decay heat power was measured in the range of 4,1 W to 90 W, within ±5 % uncertainty. Because decay heat power is closely correlated to the actual inventory of fission products, the calorimeter was proven suited for enhancing non-destructive characterization of irradiated fuel assemblies.
  • Artigo IPEN-doc 30411
    Enhanced carbon monoxide tolerance of platinum nanoparticles synthesized through the Flash Joule Heating Method
    2024 - NANDENHA, JULIO; SILVESTRIN, GABRIEL; OTUBO, LARISSA; ANDRADE, DELVONEI A.; SOUZA, RODRIGO F.B. de; ANTOLINI, ERMETE; NETO, ALMIR O.
    Was employ the Flash Joule Heating Method (FJHM) to synthesize carbon-supported Pt nanoparticles. In this method, an aqueous solution of the Pt precursorH2PtCl6·6 H2O is introduced into a reactor containing Vulcan XC 72 carbon. Subsequently, the mixture undergoes 50 cycles of discharges at 100 coulombs per discharge. Comparative XRD analysis with a commercially prepared Pt/C BASF, utilizing a reduction deposition method, reveals an expansion in the interplanar spacing of the platinum crystal lattice in the FJHM-prepared Pt/C catalyst (FJHM-Pt/C). This expansion suggests the emergence of structural defects, a finding confirmed by TEM images displaying distinct step-like features on the FJHM-Pt/C surface. Cyclic voltammogram analysis demonstrates a noteworthy increase in the oxidation pre-peak at 0.5 V for FJHM-Pt/C compared to Pt/C BASF. When employing pure H2 as fuel, the single proton exchange membrane fuel cell (PEMFC) utilizing Pt/C BASF as the anode catalyst exhibits a higher maximum power density (MPD) than its FJHM-Pt/C counterpart. Conversely, in the presence of CO, the PEMFC with FJHM-Pt/C as the catalyst demonstrates a superior MPD compared to the cell equipped with commercial Pt/C as the anode. These findings underscore enhanced CO tolerance, highlighting the potential advantages of the FJHM preparation method.
  • Artigo IPEN-doc 30397
    Convolutional neural network-based pattern recognition in natural circulation instability images
    2024 - SCHOTT, SANDRO M.C.; SILVA, MARCONES C.B. da; ANDRADE, DELVONEI A. de; MESQUITA, ROBERTO N. de
    Heat removal systems employing natural circulation are key in new nuclear power plant designs for mitigating accidents. This study applies Convolutional Neural Networks (CNNs) to classify 'chugging' instability phases, analyzing 1152 two-phase flow images from a Natural Circulation Circuit. Three CNN models, including one incorporating transfer learning from the ImageNet database, were trained via five-fold cross-validation to fine-tune hyperparameters. This involved comparing models with and without transfer learning against a baseline linear model. A model using a pre-trained Resnet50 with transfer learning accurately classified all 230 samples, outperforming the baseline linear model with an F1-Score of 0.859. The results endorse the use of CNNs with transfer learning for thermohydraulic image analysis in identifying natural circulation instability stages.
  • Artigo IPEN-doc 30445
    Gestão do conhecimento em atividades do Instituto de Controle do Espaço Aéreo
    2024 - ALMEIDA, MADISON de A.; FERNANDES, RAQUEL G. da S. de A.; ANDRADE, DELVONEI A. de
    O Instituto de Controle do Espaço Aéreo (ICEA), pauta-se em sua missão institucional pela promoção do ensino, da pesquisa e da avaliação de conformidade no SISCEAB – Sistema de Controle do Espaço Aéreo Brasileiro. É a unidade responsável por, nesse sistema que compreende centenas de instalações, como torres de controle e centros de controle por radar por todo o país, dentre outras facilidades, treinar milhares de profissionais a cada ano, entre controladores de voo, meteorologistas, especialistas em comunicações, em informações aeronáuticas, engenheiros, técnicos e outras formações. Em se tratando de uma Instituição Científico-Tecnológica, lida com a promoção da Gestão do Conhecimento (GC) em seu âmbito. E a GC, por sua vez, envolve mecanismos de retenção e de utilização de informações, sendo aplicada em variados ramos do conhecimento. Com base na pesquisa exploratória, com abordagem tanto qualitativa como quantitativa, foi criada sistemática de gestão do conhecimento, internalizando-se práticas de criação de repositórios digitais. Como resultado, produtos foram oferecidos aos profissionais que lidam com a informação e o conhecimento.
  • Artigo IPEN-doc 30444
    Desfazimento de resíduos sólidos em órgão público
    2024 - ALMEIDA, MADISON C. de; SANTANA, DONIZETE dos S.; PEIXOTO, LEANDRO de O.; ANDRADE, DELVONEI A. de
    O desfazimento de materiais permanentes no âmbito público envolve a identificação, classificação e descarte adequado de móveis, de informática e outros, seguindo diretrizes criteriosas para potencializar recursos. Busca-se conformidade legal e ética, ao mesmo tempo em que se fortalece a transparência institucional. Ao seguir as diretrizes estabelecidas por esse Regulamento, o Instituto de Controle de Espaço Aéreo (ICEA) aprimora sua gestão de ativos, garantindo a utilização eficiente de recursos, o cumprimento de normativas, além de promover uma cultura organizacional sustentável e responsável no desfazimento de materiais. A avaliação do processo de desfazimento, conforme preconizado pelo registro de ativos e desfazimento de ativos eletrônicos, proporciona eficácia na gestão, minimização de riscos, conformidade legal, transparência e otimização de recursos, culminando na citada abordagem estratégica e sustentável na administração de ativos. O trabalho objetivou prospectar a situação legal no desfazimento na organização, sendo realizada pesquisa exploratória e qualitativa, em bibliografa e legislações. Os achados aqui discutidos resultaram no registro das práticas pelas ações e medida de desempenho.
  • Artigo IPEN-doc 30443
    CAST analysis
    2024 - ALMEIDA, MADISON C. de; KATAYAMA, RICARDO A.; HIRANO, CARLOS A.M.; ANDRADE, DELVONEI A.
    There have been several flood events in our country, notably in the Southeast Region, in the last decades, where the public management faces natural causes, such as storms with heavy rains and winds, causing landslides, flooding in urban centers and, consequently, losses. According to Leveson (2019, p. 34): CAST (Causal Analysis Based on SystemsTheory) is a structured technique to analyse accident causality from a systems perspective. CAST is an analysis method, not an investigation technique. But performing the CAST analysis as the investigation proceeds will assist in identifying what questions need to be answered and what information needs to be gathered during the investigation in order to create a comprehensive explanation as to why the loss occurred and to help formulate recommendations to prevent related accidents in the future. The CAST, as an approach after the occurrence, links to STPA (System-Theoretic Process Analysis) methodology (prior to the accident). This aims to analyse an event – which may or may not result in an accident – the way that its parts, acting systemically, can be studied, reaching the confrontation of the insecure condition(s) through effective actions. The /CAST methodology was herein applied to the event “Floods in the summer of 2020 in Piracicaba/SP”. This event provides analysis completeness, according to this model. Several intervening factors are sought in this study; the accident considered here are the floods that generated material losses in the city: e.g. destroyed buildings, streets and houses flooded, leading to losses.
  • Artigo IPEN-doc 30386
    Verification and validation of seven turbulence models for a natural circulation loop under transient conditions
    2024 - ANGELO, G.; ANGELO, E.; SCURO, N.L.; TORRES, W.M.; ANDRADE, D.A.
    A numerical study of the vertical heater, vertical cooler (VHVC) natural circulation loop (NCL) at IPEN/CNEN-SP was conducted using a three-dimensional and transient mathematical model analyzed with the commercial software ANSYS CFX. The study focused on the stable and single-phase flow regime, with a Rayleigh number ranging from zero to 2.8×108. Seven turbulence models have been benchmarked: Zero Equation, Eddy Viscosity Transport Equation (EVTE), k−ω, k−ɛ, Shear Stress Transport (SST), Reynolds Stress (SSG), and Detached Eddy Simulation (DES). The results of these models were compared against each other and against experimental results obtained specifically for this purpose, focusing on the spatial distribution and temporal evolution of temperature at various points in the natural circulation loop. Among all tested models, the k−ɛ model demonstrated superior performance with the lowest average deviation, exhibiting lower initial turbulence production and buoyancy effects than the more complex models. This behavior suggests that the k−ɛ model is more accurate in predicting temperature distribution and is a better choice for transient flow analysis in natural circulation loops with similar geometries to those presented in this study.
  • Artigo IPEN-doc 30370
    Assessment of the IEA-R1 nuclear reactor using a nonstandard fuel assembly with six fuel plates of the Brazilian Multipurpose Reactor
    2024 - SOARES, HUMBERTO V.; TORRES, WALMIR M.; UMBEHAUN, PEDRO E.; BELCHIOR, ANTONIO; ANDRADE, DELVONEI A. de
    In order to qualify the fuel plates of the Brazilian Multipurpose Reactor (RMB), a nonstandard Instrumented Fuel Assembly (IFA) was designed and is being constructed to be burned in the IEA-R1 nuclear research reactor. IFA has fuel plates of different uranium densities (10 fixed fuel plates of 3.0 gU/cm3 – IEA-R1 standard; 6 removable fuel plates of 3.7 gU/cm3 – RMB; and a central aluminum plate). This paper is the first step to demonstrate that IEA-R1 can safely operate with this IFA. To verify the IFA thermal behavior inside the IEA-R1 core during reactor operation and certify the no power peaks occurrence, the power distribution was calculated for each fuel plate. LEOPARD and HAMMER-TECHNION codes were utilized to calculate the core thermal neutron cross section and CITATION code to calculate the core power distribution. Calculations were performed for 5 MW reactor power considering the IFA placed in a core peripheral position. The RMB fuel plates average power was 4.73 % higher compared to IEA-R1 fuel plates. This was expected due to the higher density of uranium in these plates. The power of each IFA fuel plate was compared with a fresh IEA-R1 Fuel Assembly (FA) at the same core position. The power in the IFA hottest plate is only 6.79 % higher than the correspondent IEA-R1 fuel plate. The IFA power distribution was also compared to the hottest FA of the core. The power of each IFA fuel plate was below its correspondent hottest FA fuel plate. In addition, the total IFA power is 18.40 % less than the hottest FA in the core. No significant power peaks occur in the IFA during operation. As future works, thermal–hydraulic calculations will be performed considering this calculated power distribution and no hot spots are expected.
  • Artigo IPEN-doc 30318
    Long-term safety and governance of nuclear energy in climate emergency cities
    2023 - CARVALHO, AMANDA R. de; RODRIGUES, ELAINE A.; ANDRADE, DELVONEI A. de; CARVALHO, BEATRIZ R. de; BUSTILLOS, JOSE O.W.V.
    The advance of urbanisation and climate change are the greatest challenges facing humanity in the coming decades. Today 55% of the human population lives in cities and it is estimated that 6.4 billion people will live in an urban environment by 2050. The inevitable consequences of global climate change can result in hard-to-measure losses and damages that include loss of life and livelihoods, degradation of physical structures, territories and agricultural land, and impairment of cultural heritage, social and cultural identity, cultural heritage, and biodiversity. Adaptation efforts are not sufficient to adequately reduce the risks associated with current and future climate impacts, and even with effective adaptation, losses and damages will not be averted. In regions that are most vulnerable to climate change, the ecological, socio-economic and physical systems are losing resilience, with human vulnerability increasing in susceptible regions such as densely populated coastal regions, with real risk of forced displacement and direct or indirect impacts on hundreds of millions of people and key infrastructure. Given the relevance of nuclear energy in achieving climate change goals as low-carbon energy and its potential to contribute in net zero transitions, the study investigates the association between the impacts of climate change and the risks posed by nuclear installations in coastal locations. The first commercial nuclear power plants began operating in the 1950s, and today nuclear power accounts for about 10 percent of all electricity worldwide, making it the world's second largest source of low-carbon energy (26 percent of the total by 2020), with more than 50 countries using nuclear power and about 420 nuclear power reactors in operation around the world, in 182 different locations, of which a good part are coastal. We identified 82 locations that correspond to the conditions. The 5 countries with the greatest number of vulnerable locations are China (18), Japan (16), United States (9), Republic of Korea (6), and the United Kingdom (5). These locations also include four megacities, with populations of over ten million people: Shenzhen e Dalian (China), Karachi (Pakistan) e Surat (India). Since the coastal locations with nuclear power reactors that are vulnerable to sea level rise concentrate millions of inhabitants, it is critical that climate resilient energy systems are designed that consider the anticipated impact of climate change, both for slow onset events and climate extremes, with a focus on the safety of people and the environment surrounding these nuclear facilities.