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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

Predicting the design relevant loadsin the engine mount systemat an early stage of thedevelopment process / Uppskattning av de konstruktionsrelevantalasterna i motorupphängningen tidigt iproduktutvecklingsprocessen

ENGEL, KATRIN January 2013 (has links)
I fordonsindustrin har det blivit allt viktigare att sänka processtider samt utvecklingskostnaderför att kunna bibehålla övertaget gentemot konkurrenterna. Det finns därför ett behov av attkontinuerligt se över både den övergripande produktutvecklingsprocessen samt subprocesser såsom konstruktionsprocesser av enskilda komponenter.Ett exempel på de sistnämnda berör konstruktionen av motorupphängningen i en Mini Cooper Smed avseende på hållfasthet, särskilt beträffande de maximallaster som uppstår. I dettaexamensarbete undersöks deras ursprung samt deras spridning i fordonet. Därefter utvecklas enmetod med vilken krafterna kan uppskattas. Detta görs för att kunna tillhandahållakonstruktionsrelevanta parametrar tidigt i utvecklingsprocessen.En manöver som ger upphov till stora laster i motorupphängningen undersöks med hänsyn tilldess primära lastorsakande effekter. Dessa analyseras var för sig med en kvasistatisk ansats ochverifieras med mätdata. För att kunna ta hänsyn till ojämnt väglag måste de påverkadekomponenternas elastokinematiska egenskaper tas hänsyn till. Därför utvecklas en modell,innehållande de tidigare bestämda effekterna.Den framtagna modellen tillhandahåller uppskattningar av de laster i motorupphängningen somorsakas av accelerationen i längsriktningen, momentet som påverkar motorn samt kombinationerav de två. Modellens komplexitet är låg då den baseras på förenklingar och uppskattningarlämpliga för det tidiga skedet i utvecklingsprocessen. Resultaten visar på hög överensstämmelsemed mätvärdena vilket tyder på ett lämpligt tillvägagångssätt gällande såväl analys sommodellering. För att generera lasterna som uppstår på grund av ojämnt väglag rekommenderas enutökning av modellen. Utöver detta föreslås en undersökning av huruvida de erhållna resultatenär giltiga för andra fordon, samt en analys av hur de ingående parametrarna påverker lasternasamt även beror av varandra / In the automotive industry, the need for more efficient processes and reduced development costshas become of increasing value in order to maintain an edge over market competitors. It istherefore important to continuously reevaluate the overall development process as well as subprocesses,such as component design processes.An example of the latter concerns the design of the engine mount system of a Mini Cooper S inregard to structural durability, in particular to the maximum forces. In this thesis, their origin aswell as their propagation through the vehicle is investigated. Subsequently, a method for theestimation of the forces is established so as to provide accurate design parameters in the earlyphase of the product development process.For this purpose, a design relevant maneuver is examined in regard to its primary load-inducingeffects. These are studied individually using a quasistatic approach, and are verified withmeasurement data. In response to road irregularities, the influenced components’ elastokinematicproperties need to be considered as well. Hence, a simulation model is established, consisting ofthe previously determined effects.The developed model provides estimations of the loads in the engine mount system as caused bylongitudinal acceleration, drive shaft torque and the combination thereof. The complexity of themodel is low as it is based on simplifications and approximations appropriate for the early stageof the development process. Yet the results show high correspondence with the measured forces,indicating a valid analytical as well as modeling approach. In order to obtain the forces asinduced by road irregularities, an extension of the current model is recommended. Additionally,it is advised to examine the transferability of the results to other vehicles, as well as determinethe influence of the system parameters on the predicted loads, as well as on each other.
12

Dynamic Tuning of Hydraulic Engine Mount Using Multiple Inertia Tracks

Barszcz, Benjamin Daniel 24 August 2010 (has links)
No description available.
13

Modelagem da dinâmica vertical de coxins elastoméricos de motor através de método de redes neurais / Modeling vertical dynamic of elastomeric engine mounts using artificial neural networks

Oliveira, Paulo Afonso Coppi Aquino de 03 October 2011 (has links)
O escopo do trabalho é a modelagem de um coxim elastomérico de motor, elemento que possui papel fundamental no isolamento vibracional do conjunto motor e transmissão. O estudo do comportamento mecânico de materiais elastoméricos é um campo que é desenvolvido a muitos anos devida complexidade e não-linearidade desses componentes; e modelos matemáticos fiéis são diferenciais competitivos. Assim essa dissertação tem como objetivo principal propor a modelagem de um coxim de motor elastomérico utilizando a técnica de redes neurais para generalizar a função de transferência entre o deslocamento do coxim e a aceleração vertical de motor. Duas abordagens de treinamento - dados experimentais coletados em bancada hidráulica uniaxial e dados experimentais coletados em campo - são apresentadas com o intuito de identificar a condição que a rede neural apresenta melhor performance de generalização. Para tal comparação uma métrica baseada em área da densidade espectral de potência é apresentada para quantificar o desempenho do modelo na faixa de frequência estudada (0-40 Hz). Finalmente é realizada uma comparação com um modelo mecânico composto por molas e amortecedores combinados. Os resultados demonstram que tanto o treinamento realizado com dados de bancada quanto o modelo mecânico apresentam boa correlação de 0 Hz a 14 Hz enquanto o treinamento realizado com dados de campo tem boa correlação de 0 Hz a 14 Hz e de 23 Hz a 40 Hz uma vez que essa abordagem tem capacidade de capturar a histerese e parte da não linearidade da borracha. É demonstrado que na faixa de frequência na qual todos modelos não foram capazes de generalizar existe modo de vibrar onde um nó no coxim estudado que dificulta a modelagem. Conclui-se que a técnica de redes neurais possui grande potencial em sua utilização, apresentando resultados bastante satisfatórios, além de outras vantagens, como a velocidade de processamento da rede treinada. / This dissertation scope is the modeling of an elastomeric mount, element which has primordial role on powertrain vibration isolation. The study of the mechanic behavior of those elastomeric materials is a field being studied for several years agor since its complexity and non-linarity of those components; and a reliable math models are competitive edge. So this dissertation has as main object purpose the modeling of an elastomeric engine mount using neural networks technician to predict the transfer function between the mount displacement and engine vertical accelerationTwo training approachs experimental data gathered in a uniaxial hydraulic bench and experimental data gathered in field are presented with the objective of identify the condition which the neural network presents better prediction performance. So this comparison being made a metric based on power density spectral area is presented to quantify the performance on the frequency range studied (0-40 Hz). Finally a comparison is made with a mechanical model composed per springs and dumpers combined. The results show that even the training made with the bench data and the mechnical model present good correlation from 0 Hz to 14 Hz while the training made with field data has good correlation from 0 Hz to 14 Hz and 23 Hz to 40 Hz once this approach has the ability to capture the hysteresis and part of rubber non-linearity. It is demonstrated that the frequency range where all the models are not capable to predict, there is a vibration mode where there is a node on the studied mount which dificults the modeling. The conclusion is that the neural network technique has great potential on its usage, presenting very satisfactory results, among other vantages as the processing speed after the network is trained.
14

Modelagem da dinâmica vertical de coxins elastoméricos de motor através de método de redes neurais / Modeling vertical dynamic of elastomeric engine mounts using artificial neural networks

Paulo Afonso Coppi Aquino de Oliveira 03 October 2011 (has links)
O escopo do trabalho é a modelagem de um coxim elastomérico de motor, elemento que possui papel fundamental no isolamento vibracional do conjunto motor e transmissão. O estudo do comportamento mecânico de materiais elastoméricos é um campo que é desenvolvido a muitos anos devida complexidade e não-linearidade desses componentes; e modelos matemáticos fiéis são diferenciais competitivos. Assim essa dissertação tem como objetivo principal propor a modelagem de um coxim de motor elastomérico utilizando a técnica de redes neurais para generalizar a função de transferência entre o deslocamento do coxim e a aceleração vertical de motor. Duas abordagens de treinamento - dados experimentais coletados em bancada hidráulica uniaxial e dados experimentais coletados em campo - são apresentadas com o intuito de identificar a condição que a rede neural apresenta melhor performance de generalização. Para tal comparação uma métrica baseada em área da densidade espectral de potência é apresentada para quantificar o desempenho do modelo na faixa de frequência estudada (0-40 Hz). Finalmente é realizada uma comparação com um modelo mecânico composto por molas e amortecedores combinados. Os resultados demonstram que tanto o treinamento realizado com dados de bancada quanto o modelo mecânico apresentam boa correlação de 0 Hz a 14 Hz enquanto o treinamento realizado com dados de campo tem boa correlação de 0 Hz a 14 Hz e de 23 Hz a 40 Hz uma vez que essa abordagem tem capacidade de capturar a histerese e parte da não linearidade da borracha. É demonstrado que na faixa de frequência na qual todos modelos não foram capazes de generalizar existe modo de vibrar onde um nó no coxim estudado que dificulta a modelagem. Conclui-se que a técnica de redes neurais possui grande potencial em sua utilização, apresentando resultados bastante satisfatórios, além de outras vantagens, como a velocidade de processamento da rede treinada. / This dissertation scope is the modeling of an elastomeric mount, element which has primordial role on powertrain vibration isolation. The study of the mechanic behavior of those elastomeric materials is a field being studied for several years agor since its complexity and non-linarity of those components; and a reliable math models are competitive edge. So this dissertation has as main object purpose the modeling of an elastomeric engine mount using neural networks technician to predict the transfer function between the mount displacement and engine vertical accelerationTwo training approachs experimental data gathered in a uniaxial hydraulic bench and experimental data gathered in field are presented with the objective of identify the condition which the neural network presents better prediction performance. So this comparison being made a metric based on power density spectral area is presented to quantify the performance on the frequency range studied (0-40 Hz). Finally a comparison is made with a mechanical model composed per springs and dumpers combined. The results show that even the training made with the bench data and the mechnical model present good correlation from 0 Hz to 14 Hz while the training made with field data has good correlation from 0 Hz to 14 Hz and 23 Hz to 40 Hz once this approach has the ability to capture the hysteresis and part of rubber non-linearity. It is demonstrated that the frequency range where all the models are not capable to predict, there is a vibration mode where there is a node on the studied mount which dificults the modeling. The conclusion is that the neural network technique has great potential on its usage, presenting very satisfactory results, among other vantages as the processing speed after the network is trained.
15

Přestavba letounu Z 142 s pohonnou jednotkou LYCOMING / Rebuilding an airplane Z 142 with a LYCOMING power unit

Šurkala, Martin January 2017 (has links)
The aim of this master´s thesis is to replace the current engine M 337AK of the aeroplane Zlin 142 for the engine of Lycoming type with an appropriate propeller. Another purpose of the study is the installation of a nose undercarriage of VUT 100 type. The first part of the thesis examines the alternatives of replacement engines. Here the individual engines are compared with regard to their flight characteristics (climbing etc.). The next part presents the calculation of new CG positions, flight envelopes and the load affecting the engine mount. Finally, the last part focuses on the constructional plan for the engine installation and the structural analysis.
16

Modeling of 3D Magnetostrictive Systems with Application to Galfenol and Terfenol-D Transducers

Chakrabarti, Suryarghya 19 December 2011 (has links)
No description available.
17

Substituição do alumínio pelo compósito de poliamida no suporte do coxim motor

Silva, Leandro Cardoso da 27 January 2014 (has links)
Made available in DSpace on 2016-03-15T19:36:41Z (GMT). No. of bitstreams: 1 Leandro Cardoso da Silva.pdf: 4262718 bytes, checksum: ac43795cdc56049895a5038a95097702 (MD5) Previous issue date: 2014-01-27 / Mounts are considered structural parts. Generally, mounts utilize metals such as aluminum and steel. These metals have high fatigue strength and its degradation temperature transmitted by the engines is very small. This work aimed to study the replacement of the aluminum mounts engine by glass fiber reinforced polyamide composite in order to reduce the mass. Polyamide reinforced with fiberglass is the choice that offers the best compromise of a recyclable material, with adequate thermal and fatigue resistance. The composite used was the commercial polyamide PA66 with 0%, 30%, 35%, 50% glass fiber. This study will focus mainly on the fatigue properties of the composite at temperatures of engine operation. The fatigue tests of the composite with glass fiber additions were performed on flexure specimens at 120°C. The fatigue behavior of the composite was analyzed using the staircase method. The results obtained in fatigue tests showed that the polyamide with 50% glass fiber has the lowest deflection. The observations of the fracture surfaces of the tested specimens were made by Scanning Electron Microscopy (SEM). These observations by SEM showed an excellent adhesion of glass fiber in the polyamide. Analyzes will also be conducted by simulation using the Finite Element Method (FEM) from fatigue results and the conditions of use of the component. The comparison by the FEM of the mounts manufactured of glass fiber reinforced polyamide composite and of aluminum alloy indicated similar results with respect to stress levels. The fatigue tests results and of the simulation by finite element method showed a good possibility of substitution of the aluminum alloy by glass fiber reinforced polyamide composite in the mounts, with a reduction in weight of 0.2 kg (32%). / Os coxins são considerados dentro das classificações automobilísticas como peças estruturais. Geralmente, os coxins utilizam metais como o alumínio e o aço em seus suportes. Esses metais oferecem grande resistência à fadiga e sua degradação na temperatura transmitida pelos motores é muito pequena. Devido à necessidade de diminuir a massa e reduzir o custo, este trabalho teve como objetivo estudar a substituição do suporte de alumínio do coxim do motor pelo compósito de poliamida reforçado com fibra de vidro. O compósito de poliamida é a escolha que melhor oferece o compromisso de um material reciclável, com resistência térmica e à fadiga, devido às suas propriedades mecânicas serem comparáveis às do alumínio. O compósito utilizado foi à poliamida comercial PA 6.6 com 0%, 30%, 35%, 50% de fibra de vidro. Este estudo focará principalmente nas propriedades em fadiga do compósito nas temperaturas de trabalho e nas análises de simulação decorrentes das propriedades obtidas e das condições de utilização do componente. Os ensaios de fadiga do compósito de poliamida com adições de porcentagens variadas de fibra de vidro foram executados em corpos de prova do tipo de flexão a 120°C. O comportamento em fadiga do compósito foi analisado utilizando-se o método staircase. As observações das superfícies de fratura dos corpos de prova ensaiados foram feitas por microscopia eletrônica de varredura e evidenciaram a excelente aderência da poliamida na fibra de vidro. Os resultados obtidos nos ensaios de fadiga, esforços máximos e esforços excepcionais permitiram concluir que o compósito de poliamida com 50% de fibra de vidro apresenta a menor deflexão. A comparação pelo Método de Elementos Finitos do suporte do coxim do motor em compósito de poliamida com reforço de fibra de vidro e da liga de alumínio indicou, de uma maneira geral, resultados similares com relação aos níveis de tensão. Contudo, os valores de deflexão apresentaram valores sistematicamente maiores no compósito. Os resultados dos ensaios mostram um bom comportamento do compósito de poliamida, dando indícios sobre a viabilidade de utilização na substituição da liga de alumínio, com uma redução em massa de 0,2 kg (32%).
18

Návrh přední časti trupu letounu TL-4000 a zástavby motoru / Design of fore part of fuselage and engine mounting of TL-4000 aircraft

Löffelmann, František January 2014 (has links)
The thesis solves mounting of Continental IO-55ON to four-seat all composite aeroplane. Weight analysis of weights carried by engine mounting was done and loads of mounting and nose gear attached directly to mounting was computed according to CS-23 regulation. Mounting was designed based on affordable information about similar aeroplanes and it was sized due to Nastran/Patran system strength analysis. Further reinforcing of fire wall, engine covers and forms for their manufacture was suggested.
19

Zástavba turbovrtulové pohonné jednotky do malého dvoumístného letounu / Turboprop powerplant installation into small twoseater airplane

Kövér, Ondřej January 2018 (has links)
The diploma thesis deals with the problem of application of turboprop engine to a small 2-seater airplane. In the first part, reasons why the application is in considered are stated. Then, the air-plane is characterised, the choice of the most suitable engine, propeller and the weight analysis is made and the centres of gravity are calculated. For chosen engine and propeller, in chapter 6, the flight performance is calculated. In chapter 7 follows calculations of flight envelopes and the lim-it positive and negative load factor is stated. Flight envelopes calculations are followed by the calculation of engine mount loads of flight and ground cases. In chapter 9, the design of engine mount, inlet and outlet system and positioning of important elements are solved. The design part is followed by strength analysis of engine mount and its attachment into engine partition.
20

Remotorizace lehkého sportovního letounu / Light sport aircraft engine replacement

Totogashvili, Nikolozi January 2020 (has links)
Práce je zaměřena na nalezení optimálního a nového motoru pro PS-28 Sport Cruiser, pro větší výkon a tah. Rotax 912 ULS je v současné době jediným motorem, který klient této práce (Czech Aircraft Works, dále jen CZAW) instaluje do letadel Sport Cruiser. Tato čtyřválcová pohonná jednotka má maximální vzletový výkon 100 hp. Pro náročnější zákazníky bude nabídka rozšířena o Lycoming O-235-L2C, což je také čtyřválcový motor s maximálním vzletovým výkonem 118 koní. Což znamená, že společnost bude mít větší možnost a klient bude mnohem spokojenější.

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