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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.
11

Modelo dinamico da lubrificação do pistão em compressores alternativos

Fernandes, Julio Romero Santos January 1996 (has links)
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnologico / Made available in DSpace on 2016-01-08T20:39:12Z (GMT). No. of bitstreams: 1 104402.pdf: 13360964 bytes, checksum: 113cc948d365d428ae37e9d63e47f3c5 (MD5) Previous issue date: 1996 / Simulação do movimento radial do pistão em um compressor alternativo de refrigeração. Esta simulação tem como objetivo promover economia de energia, diminuindo tanto a potência consumida por atrito viscoso quanto o vazamento de fluido refrigerante através da folga radial, além de reduzir o ruído do compressor.
12

Estudo do desgaste de aneis de segmento de motores de combustao interna pela tecnica dos tracadores radioativos

SANCHEZ, WLADIMYR 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:29:27Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:00:42Z (GMT). No. of bitstreams: 1 12896.pdf: 2978744 bytes, checksum: d7e5ccc0fe4014d76824c630b7e26cb8 (MD5) / Dissertacao (Mestrado) / IEA/D / Escola Politecnica, Universidade de Sao Paulo - POLI/USP
13

Caracteristicas do desgaste de aneis de pistao com diferentes tecnologias de tratamentos superficiais

GARCIA, MARCOS B. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:48:54Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:58:12Z (GMT). No. of bitstreams: 1 09605.pdf: 8733026 bytes, checksum: 49dd6903a91a39b5240ad2d704c956d5 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
14

Estudo do desgaste de aneis de segmento de motores de combustao interna pela tecnica dos tracadores radioativos

SANCHEZ, WLADIMYR 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:29:27Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:00:42Z (GMT). No. of bitstreams: 1 12896.pdf: 2978744 bytes, checksum: d7e5ccc0fe4014d76824c630b7e26cb8 (MD5) / Dissertacao (Mestrado) / IEA/D / Escola Politecnica, Universidade de Sao Paulo - POLI/USP
15

A Rapid Compression Machine with the Novel Concept of Crevice Containment

Bhari, Anil January 2010 (has links)
No description available.
16

Etude théorique, conception, réalisation et essai préliminaire d'un moteur à air chaud à pistons liquides / Theorical study, design, realization, and preliminary test of a hot liquid pistons engine

Ndame Ngangue, Max Keller 20 February 2019 (has links)
Un moteur Ericsson est un moteur alternatif à apport de chaleur externe fonctionnant selon un cyclethermodynamique de Joule. Ce type de moteur est particulièrement intéressant pour la valorisationde certaines "sources chaudes" (l'énergie solaire, la biomasse, les effluents gazeux chauds...).Dans cette thèse, une configuration innovante de moteur est proposée. Celle-ci permet d'une part,de s’affranchir du problème d’étanchéité autour des pistons des moteurs Ericsson, par l'usage despistons liquides en lieu et place des pistons mécaniques et d'autre part, de simplifier le système dedistribution mécanique des moteurs conventionnels par l'usage de soupapes commandéesparticulières, dont l'ouverture est déclenchée par contact avec le piston. Ce type de moteur estadapté pour la production d'électricité de petite puissance (jusqu'à... 10 kW).Trois lois différentes de commande des soupapes du cylindre de détente du moteur à air chaudproposé sont étudiées et leurs influences sur la conception et les performances énergétiques dusystème sont présentées. En raison de la masse importante d'eau dans le système, un modèle quiprend en compte la dynamique des colonnes de liquide est développé. Ce modèle permet de prédireles performances d'un premier prototype expérimental.Un prototype de machine de détente a ensuite été conçu et réalisé dans notre laboratoire. Uneprésentation du prototype et du banc d'essai est faite, et les résultats d'un essai préliminaire sontprésentés. Malgré le caractère préliminaire de ces résultats, ils sont très encourageants car d'unepart, ils n'ont pas révélés de problèmes techniquement délicats à résoudre, et d'autre part ils ontpermis de tirer de nombreux enseignements pour la suite des travaux à mener sur le prototype. / An Ericsson engine is a reciprocating external heat input engine operating on a Joule thermodynamiccycle. This type of engine is particularly interesting for the valorization of certain "hot sources" (solarenergy, biomass, hot gaseous effluents ...).In this thesis, an innovative engine configuration is proposed. This allows, on the one hand, toovercome the problem of tightness around the pistons of Ericsson engines, by the use of liquidpistons instead of mechanical pistons and on the other hand, to simplify the mechanical distributionsystem of conventional engines by the use of particular actuated valves, whose opening is triggered by contact with the piston. This type of motor is suitable for the production of electricity of smallpower (up to... 10 kW).Three different valve command laws for the proposed hot air motor expansion cylinder are studiedand their influences on the design and energy performance of the system are presented. Due to thelarge amount of water in the system, a model that takes into account the dynamics of the liquidcolumns is developed. This model makes it possible to predict the performances of a firstexperimental prototype.A prototype of the expansion machine was then designed and built in our laboratory. The prototypeand the test bench are presented together with the preliminary test results. Despite the preliminarynature of these results, they are very encouraging because, on the one hand, they have not revealedany technically difficult problems to be solved, and on the other hand they have made it possible todraw many lessons for the further work to be done lead on the prototype.
17

Piston slap noise : its transfer through an internal combustion engine

Oguchi, Tetsuro January 1979 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1979. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Includes bibliographical references. / Tetsuro Oguchi. / M.S.
18

Estudo de camadas finas tratadas por laser em anéis de pistão / Thin layer study treated by laser in piston rings

OLIVEIRA, FELIPE de 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:34:11Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:38Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
19

Estudo de camadas finas tratadas por laser em anéis de pistão / Thin layer study treated by laser in piston rings

OLIVEIRA, FELIPE de 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:34:11Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:38Z (GMT). No. of bitstreams: 0 / Os desenvolvimentos de novos motores têm resultado no aumento constante dos carregamentos mecânicos e térmicos dos componentes. Além de estarem expostos a condições desfavoráveis ao desgaste, os novos componentes do motor devem garantir desempenho similar, ou muitas vezes superior, aos dos componentes atuais. Para os anéis de pistão, o desempenho é dado pela sua capacidade de vedação e raspagem, que podem ser mensurados em motor pelos resultados de consumo de óleo lubrificante (COL) e fluxo de gases para o cárter (blow-by). Sendo assim, a proposta desse trabalho foi a de avaliar-se a influência do tratamento superficial a laser para endurecimento da pista de desgaste do anel de pistão de segundo canalete, em termos do desempenho de vedação e raspagem. Foram comparados dois protótipos, utilizando como padrão um anel de pistão de produção corrente, comercialmente fornecido a clientes. O efeito do tratamento térmico a laser nos anéis foi avaliado em relação a distorções dimensionais. Após isto, foram realizados testes tribológicos de bancada com o objetivo de conhecer o comportamento do anel depois do tratamento laser. De maneira geral o tratamento superficial por laser na superfície de anéis de pistão mostraram resultados significativos no aspecto aumento de dureza, com alguns deméritos no aspecto dimensional que pode interferir na boa funcionalidade do sistema tribológico anel lubrificante cilindro. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
20

Heavy Object Lifting Platform to Correct Human Balance and Posture

Raymundo, F., Quispe, G., Raymundo-Ibañeez, C. 25 November 2019 (has links)
This research document on technological development is aimed at workers in small companies, those that are developing well and soon to emerge as companies that will be positioned at the top of their labor sector. Starting from the problem at present with respect to the bad manipulation of loads it is arranged to solve the problem with established objectives to try to correct the corporal posture at the time of lifting an object with a machine that replaces the functions of the worker. The design and the solution was made based on the requirements of the worker, workers who have the need to load objects at a certain height, here the man-machine relationship, demands and desires that help to achieve the general objective are analyzed. In addition, it has the main function of this machine: To lift heavy objects of up to 150 kg of mass, this due to the implementation of a hydraulic piston in the lifting platform. The appropriate solution is an adaptation of a platform in the form of a truck forming an angle of 47.17 between the structure of the truck and the horizontal surface, this position is the most adequate so that the back does not suffer injuries during the handling of loads at work. The results give assurance that it is a machine of reliability and easy handling since it only requires an operator to control the objects and a flat position on the back without damaging the spine.

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