Transient Flow Regime
Mostrando 1-12 de 15 artigos, teses e dissertações.
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1. Influência do Regime Transiente Sobre a Microdureza e Microestrutura nos Aços ASTM-A36 e SAE-1045 Soldados pelo Processo MAG
Resumo O regime quase-estacionário pode não ser alcançado em soldagens a arco elétrico de peças de pequenas dimensões e/ou de materiais de maior condutividade térmica. Entretanto, o regime transiente sempre ocorrerá no início e no final da soldagem. Neste regime, a variação do fluxo de energia via calor pode promover variações microestruturais e
Soldag. insp.. Publicado em: 08/08/2019
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2. Modeling and hydraulic performance evaluation of a dripper device coupled to a branched water distribution network
Resumo A irrigação é responsável por aproximadamente 70% do consumo de água doce do mundo e é um dos principais fatores por trás da crescente escassez de água global. As técnicas e sistemas de irrigação são extremamente diferenciadas e complexas. Neste contexto, as ferramentas de dinâmica de fluidos computacional (CFD) ganham relevância, permit
Rev. Ambient. Água. Publicado em: 03/06/2019
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3. Gas permeability of bentonite barriers: development, construction and testing of a measurement system
Abstract This article proposes a testing device to quickly and reliably estimate the gas permeability of bentonite-based clay barriers used in landfill cover systems. The testing methodology is based on a transient gas flow regime that passes through the barrier, therefore not requiring the use of sophisticated equipment that aim to maintain constant differe
REM, Int. Eng. J.. Publicado em: 2016-12
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4. Desenvolvimento de método para medida de permeabilidade superficial de revestimentos de argamassa. / Development of method for measuring the surface permeability of coating mortar.
The phenomenon of permeability refers to the ability with which a fluid is transported through a porous medium, driven by pressure gradient between the material and the external environment. Degradation agents are conducted to the interior of mortar and concrete driven through such a phenomenon. Therefore, it is the permeability as a key parameters for durab
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 25/05/2011
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5. Avaliacao de parametros hidraulicos para modelos de distribuicao de agua no solo sob gotejamento.
As solucoes analiticas de distrubuicao de agua para ponto fonte e regime de fluxo nao-permanente sao dependentes de parametros de solos considerados constantes em suas deducoes. Erros na determinacao desses parametros implicam insucesso dessas solucoes. Este trabalho teve por objetivo avaliar o comportamento dos parametros @ da equacao de Gardner k(h) = Ks,
Pesquisa Agropecuaria Brasileira. Publicado em: 2011
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6. On the statistical steady state gas-solid flow in a riser as predicted through a two-fluid simulation
This work is concerned with the extremely high computational costs of the two-fluid simulations of gas-solid flows in risers. In a previous article [1] a procedure was proposed to speed up the simulations towards the desired statistical steady state flow regime. In this continuing article the concern is turned to the time extent that a simulation must advanc
Computational & Applied Mathematics. Publicado em: 2009
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7. Simulação de escoamentos gás-sólido reativos em leitos fluidizados circulantes / Simulation of reactive gas-solid flows in circulating fluidized beds
Circulating fluidized bed reactors are widely used in large scale applications such as catalytic cracking of petrol and coal combustion. Development and design in those areas are strongly based on demonstration plants, at extremely high costs. In this context, treatments applying computational fluid mechanics assume considerable relevance. The complex gas-so
Publicado em: 2006
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8. Sistema inteligente para detecção de vazamentos em dutos de petróleo usando transformada Wavelet e redes neurais
This work consists in the use of techniques of signals processing and artificial neural networks to identify leaks in pipes with multiphase flow. In the traditional methods of leak detection exists a great difficulty to mount a profile, that is adjusted to the found in real conditions of the oil transport. These difficult conditions go since the unevenly soi
Publicado em: 2006
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9. Transient convective heat transfer
In nature, as well as within the human-made thermal systems, the time-variable regimes are more commonly encountered, if not always, than the permanent regimes. Nevertheless, studies in convection are still more frequent in the permanent regimes, undoubtedly due to the related difficulties in calculation in terms of time and cost of computation. One may dist
Journal of the Brazilian Society of Mechanical Sciences and Engineering. Publicado em: 2005-03
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10. Concepção e estudo de um biofiltro para tratamento de compostos orgânicos voláteis COVs
In the last decade, biological purification of gaseous waste has become an important alternative to many conventional methods of exhaust air treatment. More recently, biofiltration has proved to be an effective and inexpensive method for the treatment of air contaminated with volatile organic compounds (VOCs). A biofilter consists in a reactor packed with a
Publicado em: 2005
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11. Analise termofluidodinamica de reatores nucleares de pesquisa refrigerados a agua em regime de convecção natural
The STHIRP-1 computer program, which fundamentals are described in this work, uses the principles of the subchannels analysis and has the capacity to simulate, under steady state and transient conditions, the thermal and hydraulic phenomena which occur inside the core of a water-refrigerated research reactor under a natural convection regime. The models and
Publicado em: 2004
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12. ANALYSIS IN PERMANENT REGIMEN AND THE DOMAIN OF THE TIME FOR DETENTION AND VISUALIZATION OF PROBLEMS OF TENSION CONTROL / ANÁLISE EM REGIME PERMANENTE E NO DOMÍNIO DO TEMPO PARA DETECÇÃO E VISUALIZAÇÃO DE PROBLEMAS DE CONTROLE DE TENSÃO
This work presents a methodology to investigate high voltage control problems in electrical power systems based on steady stated and time domain computer simulations. The steady state analyses determine the V-Q curves using conventional power flow models. Time domain simulation uses conventional transient stability models to reproduce the phenomenon in detai
Publicado em: 2003