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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.
21

Driver training with look ahead

Stribeck, Robert January 2010 (has links)
<p>The ambition to lower fuel consumption has been a goal for the vehicle industrysince many years.  During the first oil crisis in the seventies this first came intolight and it has become more relevant during the last years climate change debate.Fuel costs are also an issue.  Reducing lifetime costs, in which fuel is 30 %, givesa competitive advantage to the vehicle producer.  Over the years the drive trainhas been made efficient to the point where a reduction in fuel consumption due toimprovements in the drive train is highly expensive to develop.  The fact that thedriver behavior is a big factor in the vehicle’s fuel consumption has recently comeinto attention.  This master thesis has been performed at Scania in Södertälje andpresents a way to give the driver advice in advance of difficult road segments.  Theadvice will help the driver drive in a fuel efficient manner. Focus is put on a specificcase where the vehicle approaches a downhill and advice is given for the driver tolet the vehicle coast up to the start of the downhill so that the vehicle can regainits speed in the downhill.  The detection of the downhill is made with look-aheadtechnology where a GPS and a digital 3D road map makes the topography of theroad segment ahead available.</p>
22

Driver training with look ahead

Stribeck, Robert January 2010 (has links)
The ambition to lower fuel consumption has been a goal for the vehicle industrysince many years.  During the first oil crisis in the seventies this first came intolight and it has become more relevant during the last years climate change debate.Fuel costs are also an issue.  Reducing lifetime costs, in which fuel is 30 %, givesa competitive advantage to the vehicle producer.  Over the years the drive trainhas been made efficient to the point where a reduction in fuel consumption due toimprovements in the drive train is highly expensive to develop.  The fact that thedriver behavior is a big factor in the vehicle’s fuel consumption has recently comeinto attention.  This master thesis has been performed at Scania in Södertälje andpresents a way to give the driver advice in advance of difficult road segments.  Theadvice will help the driver drive in a fuel efficient manner. Focus is put on a specificcase where the vehicle approaches a downhill and advice is given for the driver tolet the vehicle coast up to the start of the downhill so that the vehicle can regainits speed in the downhill.  The detection of the downhill is made with look-aheadtechnology where a GPS and a digital 3D road map makes the topography of theroad segment ahead available.
23

Model Predictive Control for Heavy Duty Vehicle Platooning / Modellbaserad prediktionsreglering för tunga fordon i fordonståg

Kemppainen, Josefin January 2012 (has links)
The aim of platooning is to enable several vehicles to drive in a convoy while each vehicle is controlled autonomously in longitudinal direction. All vehicles in the platoon are equipped with WiFi and can therefore apply Vehicle-to-Vehicle (V2V) communication. As a result, a short intermediate distance between the vehicles can be maintained. Reduction of the aerodynamic drag is the result of the short distance, which in turn, reduces the consumed fuel. This thesis is a part of a larger project, consisting of two other theses that investigate estimation of the sensor data. Other scenarios that may arise with the platooning concept, e.g. packet losses and time synchronization of the different sensors are also analyzed. The purpose of this master thesis is to develop and evaluate a Model Predictive Control (MPC) in the concept of platooning. The main focus lies on implementation of two types of MPC, centralized and distributed, and later on integration with the other two subsystems is performed. Results from the MPC itself are evaluated, principally in terms of fuel con- sumption and computational demand. The major part of the results are based on the complete system as one unit and covers different test scenarios such as WiFi loss and non-transmitting vehicle entering the platoon. A comparison of how much energy that is consumed by the engine between an HDV driving with its cruise control and an HDV driving in a platoon has been performed. With an intermediate distance of 10 meters, driving with varying velocity and ideal signals the energy consumption got reduced with an average of 11%. / Syftet med platooning är att flera tunga fordon kör tätt efter varandra i ett fordonståg. Varje fordon regleras autonomt i longitudinell riktning och är utrustad med WiFi. Detta bidrar till att fordonen kan kommunicera med varandra och denna kommunikation, även kallad Vehicle-to-Vehicle (V2V) - communication, leder till att det relativa avståndet mellan fordonen kan minskas, vilket i sin tur leder till minskat luftmotstånd och därmed minskad bränsleförbrukning. Detta examensarbete är en del av ett större projekt som består av ytterligare två examensarbeten. De andra två hanterar estimeringen av sensordata samt behandlar förlorat sensordata och tidssynkronisering av de olika sensorerna som används. Syftet med detta examensarbete är att utveckla och utvärdera en MPC regu- lator i platooning sammanhang. Huvudfokuset ligger på implementeringen, både centraliserad och distribuerad MPC, och integreringen med de två andra delsystemen. Resultaten från enbart MPC utvärderas i termer av bränsleförbrukning och även beräkningskapactiet, då MPC är känt för att vara väldigt beräkningskrävan- de och är ofta en begränsning för hårdvaran. Den största delen av resultaten är baserade på hela systemet och täcker olika scenarion som exempelvis dålig WiFi uppkoppling och att icke−sändande fordon intar platoonen. En jämförelse av hur mycket energi motorn förbrukade har gjorts mellan ett tungt fordon som kör med farthållaren påslagen och ett tungt fordon som kör i en platoon. Med ett relativt avstånd på 10 meter, varierande hastighet och icke brusiga signaler kan bränsleförbrukning minskas med ett medel på approximativt 11%.
24

Incorporating Vehicle Emission Models into the Highway Design Process

Ko, Myung-Hoon 2011 December 1900 (has links)
Automobile transportation consumes a significant amount of non-reusable energy and emits emissions as by-products of fuel consumption. There has been much progress in the development of vehicle engine technology and alternative fuels to reduce the adverse impact of highway transportation on the environment. However, the research regarding the reduction of the adverse impact through highway design is still in its infancy. Furthermore, highway design manuals/guidebooks do not provide any information on environmentally-friendly designs. The primary objective of this research was to provide the tools and guidelines for a quantitative environmental evaluation in highway design. This research provided the results regarding the quantitative environmental impacts, by means of fuel consumption and emissions, of various highway geometric design conditions on the vertical grades as well as for horizontal and vertical crest curves that could be included in the highway design process. The researcher generated second-by-second speed profiles using the speed prediction models and non-uniform acceleration/deceleration models, and extracted the fuel consumption and emissions rates based on vehicle specific powers and speeds using recently developed motor vehicle emission simulator (MOVES). The generated speed profiles were matched with the extracted rates and aggregated during a trip on the grades and curves. In addition, the researcher conducted the environmental evaluation including a benefit-cost analysis with actual highway geometric data based on the proposed method and processes. The results demonstrated that fuel consumption and emissions could be significantly changed according to highway design conditions on grades and curves. Throughout the analyses, this research provides the guidelines and tools for environmental evaluations related to selected design features as a part of the highway development process. The provided guidelines and tools can reduce the uncertainty associated with the engineering judgment for environmentally-conscious highway design. Finally, this research shows the efficacy of environmentally-friendly design for sustainable (i.e., social, economical, and environmental) transportation.
25

A determination of motor vehicle activity factors for Atlanta, Georgia through fuel consumption analysis

Hayes, Adam Jason Otto 12 1900 (has links)
No description available.
26

Vehicle powertrain modeling and ratio optimization for a continuously variable transmission

Smith, Michael Henry 08 1900 (has links)
No description available.
27

Development of a tool to analyse helicopter performance incorporating novel systems

Porras Perucho, Henry Andres 09 1900 (has links)
The aerospace industry has always been looking forward new developments with the aim to create more environmental friendly aircraft, as well as to improve their performance. Over the last few years, a prominent research topic to achieve these challenging goals has been focussed on the incorporation of more electric Secondary Power Systems (SPS), this concept is known as More Electric Aircraft (MEA) or All Electric Aircraft (AEA) when the internal combustion engine is also replaced. Among others, Airbus is using Electro-hydrostatic Actuators, (EHAs) to combine hydraulic and electric power in A320 and A340 for flight tests since 1993. The company TTTECH applied the same concept by working on the development of an electrical steering system for an aircraft nose landing gear, and power source rationalization and electrical power flexibility in aircraft. Some of the advantages stated when the MEA concept is applied are: reduction in aircraft weight and performance penalties related to conventional SPS. Although the More/All electric aircraft concept provided satisfactory results for fixed-wing aircraft, research for rotary-wing aircraft is less common. This encourages the assessment of fuel consumption and performance penalties due to conventional and more electric SPS at conceptual level, which could achieve similar outcomes, while finding the best configuration possible. This project takes into account the previous research focused on fixed-wing aircraft and studies on new technologies for SPS within Cranfield University, this includes electrical Ice Protection System (IPS), Environmental Control System (ECS) and Actuation System (AS). Additionally, Fuel System (FS) and Electrical System (ES) capabilities were added, developing a generic tool able to predict the total power requirements depending on the flight conditions. This generic tool was then integrated with a performance model, where overall fuel consumption is calculated for a flight mission, giving continuity and improvement to the work already done. Secondary systems configuration and operating characteristics for a representative light single-engine rotary-wing aircraft were tailored, and the systems behaviour is presented. Finally, fuel consumption was calculated for a baseline mission profile, and compared to the fuel consumption when the systems are not included. The baseline mission set the initial flight conditions from which a parametric study was carried out; by varying these conditions the parametric study determined total fuel requirements for the analysed flight segments. An increment of up to %1.9 in the fuel consumption was found by integrating the proposed systems to the performance model, showing the impact produced by the systems, and the importance of studying different technologies to minimise it.
28

Desempenho operacional e energético de um microtrator em função da lastragem, velocidade de deslocamento e pressão de inflação dos pneus / Operational performance and energy of a microtractor depending on ballast, speed and inflation pressure of the tires

Araújo, Karla Lúcia Batista January 2013 (has links)
ARAÚJO, Karla Lúcia Batista. Desempenho operacional e energético de um microtrator em função da lastragem, velocidade de deslocamento e pressão de inflação dos pneus. 2013. 66 f. Dissertação (Mestrado em engenharia agrícola)- Universidade Federal do Ceará, Fortaleza-CE, 2013. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-06-24T17:17:50Z No. of bitstreams: 1 2013_dis_klbaraujo.pdf: 2251625 bytes, checksum: 094ce4c47e0d092181df65086f2f92c2 (MD5) / Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-07-21T20:17:17Z (GMT) No. of bitstreams: 1 2013_dis_klbaraujo.pdf: 2251625 bytes, checksum: 094ce4c47e0d092181df65086f2f92c2 (MD5) / Made available in DSpace on 2016-07-21T20:17:17Z (GMT). No. of bitstreams: 1 2013_dis_klbaraujo.pdf: 2251625 bytes, checksum: 094ce4c47e0d092181df65086f2f92c2 (MD5) Previous issue date: 2013 / The microtractor is ideal for activities in small areas by optimizing the work. The experiment was conducted at the Federal University of Ceará in order to evaluate the energy efficiency and operating a mechanized set microtractor rotoencanteirador-in three-speed, inflation pressure and tire ballast, with and without ballast. To obtain data for energy efficiency used a microtractor, instrumented with inductive sensors to measure wheel slippage, beakers to measure the fuel consumption and load cell for the workforce in the drawbar. The variables studied were working speed skating rotated, hourly fuel consumption, specific fuel consumption, power drawbar pull and power available. We conducted two factorial experiments for each variable evaluated, the first with microtractor without ballast and another with the use of weights, each experiment consisted of two factors: gears (1st, 2nd and 3rd) and inflation pressure of tires (82,74; 96,53 and 110,32 kPa). Data were subjected to analysis of variance test was used for comparison Tukey test at 5% significance level using the Software Assistat 7.6. The highest values were found with speeds microtractor working without ballast in third gear. The largest slip was found in third gear with microtractor without ballast and for different pressures was unbacked pressure of 82,74 kPa. The highest hourly consumption was recorded in third gear without ballast to the pressures of 96,53 kPa was without ballast. For the specific consumption the highest value was 3483.04 g.kW-1.h-1, with microtractor backed and 3267,48 g.kW-1.h-1 at a pressure of 82,74 kPa. The tensile strength in first gear was 6,02 kN, 4,81 kN in the second and third of 3,2 kN, all did not change with the change of pressure, working without ballast. Backed force was 4,81 kN, 3,2 kN and 2,00 kN in the first, second and third gear respectively. The greatest power was found in second gear without ballast. Among the most pressure was 0,48 kW at a pressure of 82,74 kW. The largest land area of 0,082 m2 was mobilized in first gear with 96,53 kPa when working without ballast. With the ballast was the largest area of 0,82 m2 in first gear with 82,74 kPa. The best efficiency of the system was in first gear to 82,74 kPa backed, 74.56%. / O microtrator é ideal para atividades desenvolvidas em pequenas áreas por otimizar o trabalho. O experimento foi desenvolvido na Universidade Federal do Ceará com o objetivo de avaliar a eficiência energética e operacional de um conjunto mecanizado microtrator-rotoencanteirador em três marchas, pressão de inflação e lastragem dos pneus, com e sem lastro. Para obtenção dos dados de eficiência energética utilizou-se um microtrator, instrumentado com sensores indutivos nas rodas para medir a patinagem, provetas para medida do consumo de combustível e célula de carga para obter a força de trabalho na barra de tração. As variáveis estudadas foram velocidade de trabalho, patinagem dos rodados, consumo horário de combustível, consumo específico de combustível, força de tração na barra e potência disponível. Realizou-se dois experimentos fatoriais para cada variável avaliada, o primeiro com o microtrator sem lastro e outro com o uso de lastros, cada experimento era composto de dois fatores: marchas (1ª, 2ª e 3ª) e pressão de inflação dos pneus (82,74; 96,53 e 110,32 kPa). Os dados foram submetidos a análise de variância, foi realizado o teste de comparação de médias de Tukey ao nível de 5% de significância utilizando o Software Assistat 7.6. Os maiores valores de velocidades foram encontrados com o microtrator trabalhando sem lastro na terceira marcha. A maior patinagem foi encontrada na terceira marcha com o microtrator sem lastro e para as diferentes pressões foi sem lastro na pressão de 82,74kPa. O maior consumo horário foi registrado na terceira marcha sem lastro, para as pressões foi de 96,53 kPa sem lastro. Para o consumo específico o maior valor encontrado foi de 3483,04 g.kW-1.h-1, com o microtrator com lastro e 3267,48 g.kW-1.h-1 na pressão de 82,74 kPa. A força de tração na primeira marcha foi de 6,02 kN, na segunda 4,81 kN e na terceira de 3,2 kN, todas não variaram com a mudança de pressão, trabalhando sem lastro. Com lastro a força foi de 4,81kN, 3,2 kN e 2,00 kN na primeira, segunda e terceira marcha respectivamente. A maior potencia encontrada foi na segunda marcha sem lastro. Entre as pressões a maior foi de 0,48 kW na pressão de 82,74 kW. A maior área de solo mobilizada foi de 0,082 m2 na primeira marcha com 96,53 kPa quando se trabalhou sem lastro. Com o lastro a maior área foi de 0,82 m2 na primeira marcha com 82,74 kPa. A melhor eficiência do sistema foi na primeira marcha a 82,74 kPa com lastro, 74,56%.
29

Determinação do rendimento na barra de tração de tratores agrícolas com tração dianteira auxiliar (4x2 Tda)

Masiero, Fabrício Campos [UNESP] 05 February 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:24:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-05Bitstream added on 2014-06-13T18:52:25Z : No. of bitstreams: 1 masiero_fc_me_botfca.pdf: 638059 bytes, checksum: abfe7790012d582df70c55bce95376dd (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O trator agrícola é a principal fonte de potência utilizada na agricultura e a maioria dos novos modelos disponíveis no mercado apresenta tração dianteira auxiliar (TDA). A preferência pelos tratores com tração dianteira auxiliar é devido à sua maior capacidade de tração, principalmente em condições trativas adversas e, sobretudo pela relação benefício e custo ser positiva e maior que os outros modelos. Esse trabalho foi realizado com o objetivo de avaliar o rendimento dinâmico na barra de tração de tratores agrícolas com tração dianteira auxiliar (4x2 TDA) em diferentes condições de superfície trativa comparando-os com os valores teóricos e práticos da bibliografia (“Fator 0,86” de Wendel Bowers e norma D497.4 ASAE, 1999) e determinar o rendimento dinâmico na barra para a superfície de solo com cobertura vegetal, pois existe pouca bibliografia e é uma realidade no Brasil com o plantio direto na palha. Avaliaram-se onze tratores agrícolas em diversas condições de ensaio de campo e condições de superfície, variando-se o tipo construtivo e modelos de conjunto de pneus, pressões de inflação dos pneus, relações entre o peso e potência do motor e velocidade teórica de deslocamento. Os dados de rendimento máximo na barra de tração do trator obtidos nos ensaios foram arranjados em grupos, obtendo-se o rendimento dinâmico médio na barra de tração e desvio padrão para cada condição de superfície. Foram coletados os dados para o cálculo do rendimento na barra de tração do trator, velocidade de deslocamento, patinagem das rodas dianteiras e traseiras do trator, consumo de combustível, força de tração e potência disponível na barra de tração.a realização do experimento, utilizou-se a Unidade Móvel de Ensaio... / The agricultural tractor is the main power source used in the agriculture and the most of available new tractor models in the marketing present auxiliary front drive (4WD). The preference for the 4WD tractors is due to biggest traction capacity, mainly in adverse tractive conditions and, mainly for the relationship benefit and cost to be positive and larger than the other models. This research was accomplished with the objective to evaluate the dynamic drawbar performance of several agricultural tractors 4WD in different surface condition (concrete, firm soil and tilled soil) comparing them with the theoretical and practical values of the bibliography (Wendel Bowers 0.86 Factor and D497.4 ASAE standard, 1999) and to determine the dynamic drawbar performance for the soil surface with vegetable covering, that doesn't exist in the bibliography and it is a reality in Brazil with the minimum cultivate. Eleven agricultural tractors were evaluated all 4WD in several field test conditions and surface conditions, being varied the tire constructive type and models, tire inflation pressures, relationships between the weight and engine power and forward speed. The maximum tractor drawbar performance obtained in the tests was arranged in groups, being obtained the medium dynamic drawbar... (Complete abstract click electronic access below)
30

Estudo da influência do escalonamento de marchas no consumo de combustível de um ônibus urbano / Study of influence of gear ratio in fuel consumption of an urban bus

Fender Neto, Jorge 16 August 2018 (has links)
Orientador: Pablo Siqueira Meirelles / Dissertação (mestrado profissional) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-16T17:37:23Z (GMT). No. of bitstreams: 1 FenderNeto_Jorge_M.pdf: 2791447 bytes, checksum: 25726f29cfa1373b250f3deb7ef10a43 (MD5) Previous issue date: 2010 / Resumo: Este trabalho consiste no estudo da influência da relação de transmissão no consumo de combustível de um ônibus urbano em uma rota específica. Com este conhecimento poderemos aperfeiçoar ainda no projeto o conjunto motor/transmissão. Avaliações da rota com a transmissão atual foram necessárias para sabermos o quão próximo à plena carga o motor está trabalhando nesta aplicação. Para esta correlação levantamos em dinamômetro curvas com 100%, 75%, 50% e 25% de carga e com as aquisições realizadas em campo foi possível avaliar qual é a reserva de torque disponível e quais as faixas de rotação mais críticas. Com o torque necessário e a velocidade do veículo devido ao seu ciclo de trabalho foi possível levantar quais relações de transmissão podem ser utilizadas e avaliar qual proporcionará menor consumo de combustível. Estudos sobre "startability" e "gradeability" são necessários para garantir que o desempenho do veículo não será prejudicado a ponto de impossibilitar a realização do serviço ao qual se propõe. Atualmente, com a evolução das normas de emissões, os recursos eletrônicos para gerenciamento do motor estão cada vez mais complexos, com elevados custos de desenvolvimento/aplicação. Este estudo é uma alternativa para o melhor aproveitamento de combustível, visando adequar a relação de transmissão ao tipo de rota/utilização do veículo, mantendo o motor o maior tempo possível em suas faixas de melhor rendimento / Abstract: The main objective of this document is the study of transmission influence in the fuel consumption of a bus on a specified route. With this knowledge we can improve in the Project the set engine / transmission. Route evaluation was necessary to know how close to full load this vehicle is working, to this correlation we take on a dynamometer the partial curves with 100%, 75%, 50% e 25% of load and with field data acquisition is possible to evaluate the torque back-up available and the more critical rotation tracks. With the necessary torque and the vehicle speed due to its cycle of work we can raise which relations of transmission can be used to evaluate which will provide the minor fuel consumption. Startability and gradeability evaluations are needed to ensure that the vehicle performance will not be impaired to preclude the service which is proposed. Currently, with the development of emission standards, the electronic resources to manage the engine are increasingly complex, with high costs of development / implementation. This study is an alternative to the better use of fuel, looking forward to adequate the transmission relation to the type of route / use of the vehicle, keeping the engine the furthest time possible in its tracks to a better consumption / Mestrado / Dinâmica / Mestre em Engenharia Automobilistica

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