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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.
1

Validation of the physical effect implementation in a simulation model for the cylinder block/valve plate contact supported by experimental investigations

Wegner, Stephan, Löschner, Fabian, Gels, Stefan, Murrenhoff, Hubertus 27 April 2016 (has links) (PDF)
Overall losses in swash plate type axial piston machines are mainly defined by three tribological interfaces. These are swash plate/slipper, piston/cylinder and cylinder block/valve plate. Within a research project, funded by the German Research Foundation, a combined approach of experimental research and simulation is chosen to acquire further knowledge on the cylinder block/valve plate contact. The experimental investigations focus on the friction torque within the contact and the measurement of the cylinder block movement in all six degrees of freedom. Simultaneously a simulation model is created focusing on the main physical effects. By considering the results of the experimental investigations significant physical effects for the simulation model are assessed. Within this paper a first comparison between experimental results and the simulation is presented, showing that for a qualitative match the implemented effects (mainly the fluid film, solid body movement, solid body contact, surface deformation) are sufficient to model the general behaviour of theinvestigated pump.
2

An Investigation of the Impact of the Elastic Deformation of the End case/Housing on Axial Piston Machines Cylinder Block/Valve Plate Lubricating Interface

Chacon, Rene, Ivantysynova, Monika 27 April 2016 (has links) (PDF)
The cylinder block/valve plate interface is a critical design element of axial piston machines. In the past, extensive work has been done at Maha Fluid Power Research center to model this interface were a novel fluid structure thermal interaction model was developed which accounts for thermal and elasto-hydrodynamic effects and has been proven to give an accurate prediction of the fluid film thickness. This paper presents an in-depth investigation of the impact of the elastic deformation due to pressure and thermal loadings of the end case/housing on the performance of the cylinder block/valve plate interface. This research seeks to understand in a systematic manner the sensitivity of the cylinder block/valve plate interface to the structural design and material properties. A comparison between simulations results is done by utilizing different end case designs and material compositions, both in the valveplate and end case solids.
3

Desenvolvimento de uma metodologia para o projeto mecânico de um bloco de motor / Development of a methodology for the mechanical project of an engine block

Almeida, Igor Raniê Soares de [UNESP] 08 August 2016 (has links)
Submitted by IGOR RANIÊ SOARES DE ALMEIDA null (igor.almeida@hydrostec.com.br) on 2016-10-06T14:43:05Z No. of bitstreams: 1 ALMEIDA_IRS_ME_GUARA - DISSERTAÇÃO.pdf: 15313376 bytes, checksum: 18d93699ff19c9c948547b05bfbe3cdc (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-10-11T12:50:26Z (GMT) No. of bitstreams: 1 almeida_irs_me_guara.pdf: 15313376 bytes, checksum: 18d93699ff19c9c948547b05bfbe3cdc (MD5) / Made available in DSpace on 2016-10-11T12:50:26Z (GMT). No. of bitstreams: 1 almeida_irs_me_guara.pdf: 15313376 bytes, checksum: 18d93699ff19c9c948547b05bfbe3cdc (MD5) Previous issue date: 2016-08-08 / O MCI (Motor de Combustão Interna) é um produto largamente utilizado na indústria, o que o torna um objeto interessante de estudo, o qual requer constante desenvolvimento com implementação de novas tecnologias. Buscando contribuir para o avanço tecnológico na área, foi realizado um estudo do comportamento estrutural de uma de suas principais peças o bloco de cilindros. O mesmo é responsável pela união de todos os outros elementos, devendo ser suficientemente rígido para absorver os esforços oriundos da explosão no interior da câmara e resultantes das forças de oscilação de primeira e segunda ordem originárias das massas dos elementos oscilatórios do motor. Nesta dissertação desejando definir o carregamento principal sobre o bloco do motor, foram realizados diversos estudos, dentre eles: a regulagem da carga onde analisa-se analiticamente as transferências de gases que circulam em um motor, também foi realizada uma análise estequiométrica do combustível, determinando a sua composição e seu poder calorífico, na sequência foram determinados os parâmetros que caracterizam um motor, definidos aqui como cálculos de desempenho, estes foram inter-relacionados em uma planilha de Excel. Posteriormente o carregamento principal do bloco foi definido, realizando estudos de casos, com influência sobre a pressão de trabalho dos cilindros, dividindo-os em fatores de carga. A modelagem do bloco foi realizada no software Autodesk Inventor 2012, as dimensões e posicionamentos das partes foram definidas segundo a realização de cálculos e dimensões de projeto como: cálculos de tração nas roscas do cabeçote e dos mancais do motor; medidas de diâmetro e curso dos pistões; cálculos da velocidade média dos pistões, distâncias das engrenagens de distribuição e relações de cálculo como o raio da manivela sobre o comprimento da biela. Como resultado da modelagem obteve-se um sólido 3D o qual foi analisado no software Ansys Work Bench versão V12, definido o carregamento total sobre o bloco, ao final obteve-se uma análise gráfica dos deslocamentos totais, das tensões equivalentes, cortantes, normais e uma análise de fadiga do bloco do motor e sua capa do mancal, obtendo uma resposta estrutural direta para os cálculos analíticos de desempenho e os estudos de caso. / The ICM (Internal Combustion Engine) is a product widely used in the industry, which makes it an interesting object of study, which requires constant development with implementation of new technologies. Seeking to contribute to the technological advancement in the area, was accomplished a study of the structural behavior of one of its main parts the engine block. It is responsible for the union of all the other elements and must be sufficiently rigid to absorb the efforts originated of the blast within the cylinders and resultants of oscillation forces of first and second order originating from the masses of the oscillation elements from the engine. In this dissertation wishing define the main load on the engine block, were performed several studies, among them: the charge of regulation where it is analyzed analytically the transfers of the gases circulating in an engine, it also performed a stoichiometric fuel analysis, determining the composition and calculating its calorific power, in the sequence was determined several parameters that characterize an engine defined as performance calculations, they were interrelated in an Excel spreadsheet. Posteriorly the main load block was defined, realizing case studies, within influence on the work pressure of the cylinders, dividing them into load factors. The modeling of the block was performed in the Autodesk Inventor 2012 software, the dimensions and positions of the parties of the 3D block model were defined according the according performance calculations and according to project dimensions such as for example: traction calculations in the head screws and engine bearings; measurements of diameter and stroke of the pistons; distances of timing gears and calculation relations as crank radius over the length of the rod. As a result there was obtained an 3D model, which was analyzed in Ansys Workbench V12 software, defined the main loading on the block, at the end was obtained a graphical analysis: of total displacements; of the equivalent stresses; shear stress; normal stress and an fatigue analysis of the engine block and engine bearings cape, getting a direct structural response to the analytical calculations of the performance and of the cases studies.
4

An Investigation of the Impact of the Elastic Deformation of the End case/Housing on Axial Piston Machines Cylinder Block/Valve Plate Lubricating Interface

Chacon, Rene, Ivantysynova, Monika January 2016 (has links)
The cylinder block/valve plate interface is a critical design element of axial piston machines. In the past, extensive work has been done at Maha Fluid Power Research center to model this interface were a novel fluid structure thermal interaction model was developed which accounts for thermal and elasto-hydrodynamic effects and has been proven to give an accurate prediction of the fluid film thickness. This paper presents an in-depth investigation of the impact of the elastic deformation due to pressure and thermal loadings of the end case/housing on the performance of the cylinder block/valve plate interface. This research seeks to understand in a systematic manner the sensitivity of the cylinder block/valve plate interface to the structural design and material properties. A comparison between simulations results is done by utilizing different end case designs and material compositions, both in the valveplate and end case solids.
5

Validation of the physical effect implementation in a simulation model for the cylinder block/valve plate contact supported by experimental investigations

Wegner, Stephan, Löschner, Fabian, Gels, Stefan, Murrenhoff, Hubertus January 2016 (has links)
Overall losses in swash plate type axial piston machines are mainly defined by three tribological interfaces. These are swash plate/slipper, piston/cylinder and cylinder block/valve plate. Within a research project, funded by the German Research Foundation, a combined approach of experimental research and simulation is chosen to acquire further knowledge on the cylinder block/valve plate contact. The experimental investigations focus on the friction torque within the contact and the measurement of the cylinder block movement in all six degrees of freedom. Simultaneously a simulation model is created focusing on the main physical effects. By considering the results of the experimental investigations significant physical effects for the simulation model are assessed. Within this paper a first comparison between experimental results and the simulation is presented, showing that for a qualitative match the implemented effects (mainly the fluid film, solid body movement, solid body contact, surface deformation) are sufficient to model the general behaviour of theinvestigated pump.
6

Hodnocení mechanických a strukturních vlastností nového bloku / Evaluation of mechanical and structural properties of new block

Lefner, Jiří January 2009 (has links)
The purpose of this dilploma thesis is to evaluate mechanical and structural properties of two types casts of Al-alloy (components of the engine block) which were made by different technologies. Die casting with local squeeze casting and without local squeeze casting. First of them is used in lot manufacture of the current engine block. The aim of the foundry is to change the technology and start to produce new block by the die casting without local squeeze casting. The samples were taken from the both parts (lower and upper part) of the current and the new engine block which are made in foundry of Skoda Auto a.c. in Mladá Boleslav. Sets of mechanical and structural properties were selected, evaluated and tested by statistical programs. It was used fifty casts of the engine blocks for the experiment.
7

Alterações metalúrgicas e topográficas do cilindro de bloco de motor de combustão interna flex-fuel. / Metallurgical and topographical alterations of the engine block cylinder of a flexible-fuel internal combustion engine.

Santos Filho, Dinecio dos 09 May 2013 (has links)
O presente estudo descreve as alterações metalúrgicas e topográficas do cilindro de blocos de motor de combustão interna fabricados em ferro fundido cinzento, após a realização de testes de durabilidade em dinamômetro. O motor testado tem tecnologia Flex-Fuel, e pode ser operado com qualquer proporção de mistura gasolina comum/etanol. Um motor foi testado com combustível etanol e o outro com gasolina comum, buscando-se assim representar duas condições extremas de trabalho em termos de combustível. A pesquisa constituiu-se da revisão bibliográfica e da parte prática que envolveu: a realização de testes de durabilidade de motor em dinamômetro; a caracterização metalúrgica e topográfica do cilindro após teste com ambos os combustíveis, utilizando técnicas de microscopia eletrônica de varredura, metalografia por microscopia óptica, perfilometria e quantificação de parâmetros de rugosidade, entre outros; a análise crítica, discussão dos resultados e apresentação da conclusão. / The present study approaches the metallurgical and topographical alterations on the cylinder of an internal combustion engine block made of gray cast iron, after durability dynamometer tests. The tested engine has flexible fuel technology (Flex-Fuel), and is capable to work with both gasoline/ethanol fuels, in any mixture proportion. One engine has been tested with ethanol and another one tested with gasoline, and so representing two extreme conditions on which the engine may work in terms of fuel. The research has been developed basically through the conceptual approach by the bibliographic review and the experimental steps that involved: general engine durability test at dynamometer bench; metallurgical and topographic characterization analysis at laboratory, after the test with both fuels, applying Scanning Electronic Microscopy SEM, optical microscopy metallography, profilometer and roughness parameters quantification, and so forth; critical analysis on the results, discussion and final conclusion.
8

Alterações metalúrgicas e topográficas do cilindro de bloco de motor de combustão interna flex-fuel. / Metallurgical and topographical alterations of the engine block cylinder of a flexible-fuel internal combustion engine.

Dinecio dos Santos Filho 09 May 2013 (has links)
O presente estudo descreve as alterações metalúrgicas e topográficas do cilindro de blocos de motor de combustão interna fabricados em ferro fundido cinzento, após a realização de testes de durabilidade em dinamômetro. O motor testado tem tecnologia Flex-Fuel, e pode ser operado com qualquer proporção de mistura gasolina comum/etanol. Um motor foi testado com combustível etanol e o outro com gasolina comum, buscando-se assim representar duas condições extremas de trabalho em termos de combustível. A pesquisa constituiu-se da revisão bibliográfica e da parte prática que envolveu: a realização de testes de durabilidade de motor em dinamômetro; a caracterização metalúrgica e topográfica do cilindro após teste com ambos os combustíveis, utilizando técnicas de microscopia eletrônica de varredura, metalografia por microscopia óptica, perfilometria e quantificação de parâmetros de rugosidade, entre outros; a análise crítica, discussão dos resultados e apresentação da conclusão. / The present study approaches the metallurgical and topographical alterations on the cylinder of an internal combustion engine block made of gray cast iron, after durability dynamometer tests. The tested engine has flexible fuel technology (Flex-Fuel), and is capable to work with both gasoline/ethanol fuels, in any mixture proportion. One engine has been tested with ethanol and another one tested with gasoline, and so representing two extreme conditions on which the engine may work in terms of fuel. The research has been developed basically through the conceptual approach by the bibliographic review and the experimental steps that involved: general engine durability test at dynamometer bench; metallurgical and topographic characterization analysis at laboratory, after the test with both fuels, applying Scanning Electronic Microscopy SEM, optical microscopy metallography, profilometer and roughness parameters quantification, and so forth; critical analysis on the results, discussion and final conclusion.

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