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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
801

Projeto estrutural do cubo do rotor de uma turbina hidraúlica tipo Kaplan

Barbosa, Rodolfo dos Santos [UNESP] 20 February 2013 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:28:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-02-20Bitstream added on 2014-06-13T18:07:42Z : No. of bitstreams: 1 barbosa_rs_me_guara.pdf: 1181057 bytes, checksum: c5662c02692da1fa2b849f6b72ca3b48 (MD5) / Neste trabalho, uma revisão teórica é feita com o intuito de fornecer embasamento teórico ao projeto para estudar a viabilidade de implementar uma melhoria que é substituir o material do cubo do rotor de um aço carbono fundido (ASTM A 216 Gr.WCC) por uma liga de alumínio fundida (A 201.0), sendo analisadas todas as vantagens e desvantagens desta modificação. Foi utilizado o método dos elementos finitos para o cálculo do cubo do rotor de uma turbina hidráulica do tipo Kaplan. Projeto, cálculo e execução rigorosos são necessários para a concepção deste componente. Para isso, é desenvolvido um estudo de caso que contempla, passo a passo, a metodologia utilizada. Uma análise estrutural do cubo do rotor de uma turbina hidráulica tipo Kaplan é utilizada no estudo de caso / In this work, a theoretical review is done in order to provide theoretical basis for the project to study the viability of implementing an improvement that would replace the material of the rotor hub of a cast carbon steel (ASTM A 216 Gr.WCC) by a cast aluminum alloy (A 201.0), and analyzed the advantages and disadvantages of this modification. It's necessary using the Finite Element Method for calculating the rotor hub of a Kaplan hydraulic turbine. Design, calculation and execution are crucial to the design of this component. For this, it is developed a case study that includes step by step, the methodology used. The analysis of the rotor hub of a Kaplan hydraulic turbine be used in the case study
802

Implementacao de queima espacial modificando o programa nodal baseado no metodo de elementos finitos e matriz resposta

YORIYAZ, HELIO 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:32:07Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:55Z (GMT). No. of bitstreams: 1 02450.pdf: 2194932 bytes, checksum: 6259550accee46685ee00ef1e038cf62 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
803

Metodologia de projeto estrutural de bombas centrífugas verticais de poço úmido / Methodology for Wet sump centrifugal vertical pumps structural design

LOESER, SERGIO 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:33:48Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:03:59Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP
804

Mathematical modelling of welding : sensitivity of residual stresses and thermal dilatations on welding parameters

Philander, Oscar January 1998 (has links)
Thesis (MTech (Mechanical Engineering))--Peninsula Technikon, 1998. / In South Africa, the determination of residual stress distribution and undesirable metallurgical phase fractions that are formed in components during welding are been dealt with in a destructive or semi-destructive manner. This dissertation is an attempt at enhancing the acquisition of residual components found in welded structures. It shows how finite element methods can be used to obtain these results. TIG welding is modeled as a thermo-mechano-metallurgical (TMM) problem. The mathematical and finite element models for welding described in this study is based on the work performed by Ronda and Oliver. These models has not yet fully been incorporated into any of the existing computational tools and therefor, a commercial computational software program, SYSWELD 2, was employed to perform the welding simulations. The Leblond material models are incorporated into this software program, and the model that is used for this study is described in this text. Computational simulations were performed to study the effects that the sensitivity of welding parameters would have on the resulting shape and size of Heat Affected Zones, depth and width of penetration, temperature fields, metallurgical solid phase fractions, as well as residual stress distribution and deformation. The results of these simulations were compared to laboratory experiments.
805

The integration of computer aided design and finite element analysis tools using a logic based approach

De Beer, Jason David January 2002 (has links)
A thesis submitted in compliance with the requirements for the Masters Degree in Technology: Mechanical Engineering, Technikon Natal, 2002. / Today's powerful computer-aided engineering (CAE) products have reached ground breaking levels of sophistication when compared with the almost archaic technology used by our predecessors. Engineers are able to develop complex three-dimensional models, or virtual prototypes, using powerful 3D modelling capabilities, and from these models, generate manufacturing drawings, motion analysis models, and even finite element models. / M
806

Implementacao de queima espacial modificando o programa nodal baseado no metodo de elementos finitos e matriz resposta

YORIYAZ, HELIO 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:32:07Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:55Z (GMT). No. of bitstreams: 1 02450.pdf: 2194932 bytes, checksum: 6259550accee46685ee00ef1e038cf62 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
807

Metodologia de projeto estrutural de bombas centrífugas verticais de poço úmido / Methodology for Wet sump centrifugal vertical pumps structural design

LOESER, SERGIO 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:33:48Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:03:59Z (GMT). No. of bitstreams: 0 / O projeto de bombas centrífugas verticais de poço úmido tem forte dependência do arranjo de cada planta. Cada situação torna-se assim um projeto particular e exige uma mútua cooperação entre os fabricantes do equipamento, responsáveis pelo projeto e testes das bombas, e os proprietários e montadores das plantas, responsáveis pela montagem e instalações das bombas verticais e respectivas tubulações no campo. Após uma ampla pesquisa bibliográfica, evidenciou-se a ausência de uma metodologia de projeto estrutural que contemple de forma integrada o projeto estrutural de todas as partes envolvidas, isto é, as bombas, as estruturas e os edifícios onde elas são instaladas. Para o desenvolvimento da dissertação, as bombas verticais foram divididas em três partes: corpo de sucção, coluna e corpo superior. Foram analisados três casos de estudo por meio de modelagem por elementos finitos. Ficou evidenciada a necessidade de uma metodologia de projeto estrutural, baseada na identificação dos problemas e das suas causas e de alternativas estruturais mais adequadas para eliminá-los ou reduzi-los. Considerando a dificuldade de testar estas bombas numa bancada de testes do fabricante, montadas de modo similar ao que trabalharão no campo e o fato de que resolver problemas destas bombas no campo é muito difícil e em certos casos até mesmo impossível, ficou evidenciado que a metodologia de projeto estrutural proposta constitui um conjunto de recomendações de grande importância nas aplicações de bombas centrífugas verticais de poço úmido. O desenvolvimento foi feito de modo geral, mas esta metodologia pode e deve ser utilizada em centrais nucleares de potência. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP
808

Stress evaluation of a monolithic refractory concrete rotary calciner lining for Tioxide Southern Africa

Ilbury, M. W. January 1993 (has links)
Presented in partial fulfillment of the requirements for the Masters Diploma in Technology: Civil Engineering, Technikon Natal, 1993. / M
809

Probabilistic modelling of heterogeneous media

Feng, Jianwen January 2013 (has links)
No description available.
810

Finite element methods for some elliptic problems with singularity and problems on unbounded domains

Jin, Jicheng 01 January 2004 (has links)
No description available.

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