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Utilização de dinamômetro de rolo de baixa potência em veículo supereconômico; Utilization of a low-power roll dynamometer in a low fuel consumption vehicle

Dornelles, Renato Tonin
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Trabalho de Conclusão de Curso Formato: application/pdf
POR
Relevância na Pesquisa
66.38%
O presente trabalho visa auxiliar o desenvolvimento de um veículo supereconômico pelo Departamento de Engenharia Mecânica. Buscando tecnologias para a redução do consumo de combustível, procurou-se a melhoria da eficiência através da redução de perdas. Foram realizados testes em um protótipo produzido pela ULBRA em um dinamômetro de rolo de baixa potência, tendo como principal parâmetro de referência a potência do motor. Foram feitas seis medições com diferentes parâmetros de lubrificação, peso e pressão de pneus, com o objetivo de analisar as diferenças presentes na potência. Avaliando as incertezas de medição presentes nos resultados finais, pode-se afirmar que a maior pressão nos pneus traseiros (50 PSI), a lubrificação das correntes e rolamentos e o menor peso possível no chassi representam um aumento na potência na roda para uma mesma posição do pedal do acelerador.; This work seeks to support the development of a low fuel consumption vehicle for the Department of Mechanical Engineering. Searching for technologies to reduce fuel consumption, it was looked to improve the efficiency by reducing losses. Tests were conducted on a prototype produced by ULBRA on a low-power roll dynamometer, having the engine power as the main benchmark parameter. Six measurements were made with different parameters of lubrication...

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

Jorge Fender Neto
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 30/07/2010 PT
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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...

Projeção do consumo de combustíveis e de emissões no transporte urbano municipal - estudos de casos : São Paulo e Bogotá; Projection of fuel consumption and emissions from urban transport - case studies : São Paulo and Bogotá

Andrea Juliana Ortiz Jerez
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 28/01/2011 PT
Relevância na Pesquisa
66.32%
O aumento da demanda de combustíveis e a conseqüente elevação dos níveis de emissões dos veículos de transporte rodoviário nas últimas décadas intensificam as preocupações sobre a segurança no suprimento de petróleo, poluição do ar e aquecimento global ao redor do mundo. As frotas de cidades densamente povoadas como São Paulo e Bogotá não tem sido devidamente acomodadas pela infraestrutura disponível, agravando a qualidade de vida de suas populações. O atual quadro do setor de transporte urbano nas cidades de São Paulo e Bogotá e sua possível evolução, em termos de veículos utilizados no transporte urbano, sua infra-estrutura e consumo de combustíveis constituem os focos deste trabalho. Para analisar tendências da demanda de combustíveis, emissões de poluentes e de gases de efeito estufa no transporte urbano de passageiros, nestas cidades, foi desenvolvido um modelo de projeção do tipo misto econométrico/simulação. São considerados dois cenários para as projeções. O primeiro, denominado "de referência", contempla a manutenção da evolução atual do transporte urbano, enquanto o segundo, denominado "alternativo", contempla uma evolução favorável da economia e o uso de novas tecnologias nos modos de transporte...

Análise de consumo de combustível em veículo automotor hibridizado; Analysis of fuel consumption in hybridized automotive vehicle

Eduardo dos Santos Costa
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 17/12/2014 PT
Relevância na Pesquisa
66.38%
Veículos Elétricos Híbridos representam, atualmente, uma alternativa para a redução do consumo de combustível fóssil utilizado pelos motores de combustão interna. Este trabalho analisa, em uma plataforma de simulação computacional e em condição experimental, o consumo de combustível de um veículo automotor, antes e após a hibridização. As simulações computacionais auxiliam, através de modelos matemáticos, um maior entendimento dos fenômenos físicos relacionados com os problemas de engenharia. Um modelo computacional bem elaborado possui um elevado grau de fidelidade em relação aos sistemas reais, tornando-se assim uma poderosa ferramenta de análise. A realização de experimentos, além de permitir uma comprovação de resultados, contribui para um refinamento dos modelos simulados. A tecnologia híbrida em estudo caracteriza-se pelo acoplamento de dois motores elétricos diretamente nas rodas traseiras do veículo. Por fim, busca-se a verificação da similaridade de comportamentos e/ou investigação de possíveis divergências entre o modelo matemático desenvolvido e os experimentos realizados. Um modelo de dinâmica veicular longitudinal descrito pela literatura é implementado no software Matlab/SimulinkTM e os resultados são comparados com os experimentos realizados em um dinamômetro de chassi.; Hybrid Electric Vehicles currently represent an alternative to reducing fossil fuel consumption used by internal combustion engines. This paper analyses...

The effect of Gang Angle of Offset Disc Harrows on Soil Tilth, Work Rate and Fuel Consumption

Serrano, João M.; Peça, José M.; Pinheiro, Anacleto C.; Carvalho, Mário J.; Nunes, Mário C.; Ribeiro, Luís; Santos, Fernando
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
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In offset disc harrows, the angle between gangs may be changed to meet the field conditions. Tractor drivers usually use an angle close to maximum, increasing power requirements and therefore limiting the forward speed and, consequently, the work rate. The objective of this work was to study, in the specific soil conditions present in Southern Portuguese agriculture, the effect of working with a disc harrow at a reduced gang angle and at a higher forward speed, in terms of work rate, fuel consumption per hectare and distribution of dry soil aggregates. A trailed type medium-weight offset disc harrow (20 discs of 610mm diameter) was used, pulled by a four wheel drive tractor. A portable computer based record system was used to collect engine speed, actual forward speed, slip, fuel consumption and draught force. Higher work rates and lower values of fuel consumption per hectare were attained, with no visible difference in soil tilth, by operating the disc harrow at a lower angle between disc gangs and shifting up to a higher gear ratio whilst maintaining engine speed. Tractor drivers, particularly those with tractors equipped with performance monitors should consider setting, by preliminary tests prior to the main field work, the right combination of gang angle and forward speed within the limits of quality of the work and the safety of the operation.

A Statistical Model of Vehicle Emissions and Fuel Consumption

Cappiello, Alessandra; Chabini, Ismail; Lue, Alessandro; Zeid, Maya Abou; Nam, Edward K.
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
Formato: 590971 bytes; application/pdf
EN_US
Relevância na Pesquisa
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Many vehicle emission models are overly simple, such as the speed dependent models used widely, and other models are sufficiently complicated as to require excessive inputs and calculations, which can slow down computational time. We develop and implement an instantaneous statistical model of emissions (CO2, CO, HC, and NOx) and fuel consumption for light-duty vehicles, which is simplified from the physical loadbased approaches that are gaining in popularity. The model is calibrated for a set of vehicles driven on standard as well as aggressive driving cycles. The model is validated on another driving cycle in order to test its estimation capabilities. The preliminary results indicate that the model gives reasonable results compared to actual measurements as well as to results obtained with CMEM, a well-known load-based emission model. Furthermore, the results indicate that the model runs fast and is relatively simple to calibrate. The model presented can be integrated with a variety of traffic models to predict the spatial and temporal distribution of traffic emissions and assess the impact of ITS traffic management strategies on travel times, emissions, and fuel consumption.; Ford Motor Company through the Ford-MIT Alliance.

A Statistical Model of Vehicle Emissions and Fuel Consumption

Cappiello, Alessandra; Chabini, Ismail; Nam, Edward K.; Lue, Alessandro; Zeid, Maya Abou
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
Formato: 739550 bytes; application/pdf
EN_US
Relevância na Pesquisa
66.38%
A number of vehicle emission models are overly simple, such as static speed-dependent models widely used in practice, and other models are sophisticated as to require excessive inputs and calculations, which can slow down computational time. We develop and implement an instantaneous statistical model of emissions (CO2, CO, HC, and NOx) and fuel consumption for light-duty vehicles, which is derived from the physical loadbased approaches that are gaining in popularity. The model is calibrated for a set of vehicles driven on standard as well as aggressive driving cycles. The model is validated on another driving cycle in order to assess its estimation capabilities. The preliminary results indicate that the model gives reasonable results compared to actual measurements as well as to results obtained with CMEM, a well-known load-based emission model. Furthermore, the results indicate that the model runs fast and is relatively simple to calibrate. The model presented can be integrated with a variety of traffic models to predict the spatial and temporal distribution of traffic emissions and assess the impact of ITS traffic management strategies on travel times, emissions, and fuel consumption.

An Analysis of Various Policy Instruments to Reduce Congestion, Fuel Consumption and CO2 Emissions in Beijing

Anas, Alex; Timilsina, Govinda R.; Zheng, Siqi
Fonte: Banco Mundial Publicador: Banco Mundial
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Using a nested multinomial logit model of car ownership and personal travel in Beijing circa 2005, this paper compares the effectiveness of different policy instruments to reduce traffic congestion and CO2 emissions. The study shows that a congestion toll is more efficient than a fuel tax in reducing traffic congestion, whereas a fuel tax is more effective as a policy instrument for reducing gasoline consumption and emissions. An improvement in car efficiency would also reduce congestion, fuel consumption, and CO2 emissions significantly; however, this policy benefits only richer households that own a car. Low-income households do better under the fuel tax policy than under the efficiency improvement and congestion toll policies. The congestion toll and fuel tax require the travel cost per mile to more than triple. The responsiveness of aggregate fuel and CO2 are, approximately, a 1 percent drop for each 10 percent rise in the money cost of a car trip.

Transportation Fuel Use, Technology and Standards : The Role of Credibility and Expectations

Eskeland, Gunnar S.; Mideksa, Torben K.
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
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There is a debate among policy analysts about whether fuel taxes alone are the most effective policy to reduce fuel use by motorists, or whether to also use mandatory standards for fuel efficiency. A problem with a policy mandating fuel economy standards is the "rebound effect," whereby owners with more efficient vehicles increase vehicle usage. If an important part of negative externalities from transport are associated with vehicle kilometers (accidents, congestion, road wear) rather than fuel consumption, the rebound effect increases negative externalities. Taxes and standards should be mutually supportive because fuel taxes often meet political resistance. Over time, fuel efficiency standards can reduce political resistance to fuel taxes. Thus, by raising fuel efficiency standards now, politicians may be able to pursue higher fuel tax paths in the future. Another argument in support of fuel efficiency standards and similar policies is that standards to a greater extent than taxes can be announced in advance and still be credible and change the behavior of inventors...

Political Determinants of Fossil Fuel Pricing

van Beers, Cees; Strand, Jon
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
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56.63%
This paper provides an empirical analysis of economic and political determinants of gasoline and diesel prices for about 200 countries over the period 1991-2010. A range of both political and economic variables are found to systematically influence fuel prices, and in ways that differ systematically with countries per-capita income levels. For democracies, the analysis finds that fuel prices correlate positively with both duration of democracy and tenure of democratic leaders. In non-democratic societies there is more often no such relationship or it is the opposite of that for democracies. Regime switches -- transitions from non-democratic to democratic government, or vice versa -- reduce fuel prices. Fuel prices are also lower for more corrupt, or more centralized, governments. Higher levels of gross domestic product per capita lead to higher fuel prices, while export income from selling fossil fuels reduces these prices dramatically. Higher motor fuel consumption also appears to reduce fuel prices, most for gasoline. Absolute "pass-through" of crude oil price changes to fuel prices is found to be high on average.

Haiti: Strategy to Alleviate the Pressure of Fuel Demand on National Woodfuel Resource

World Bank; Ministry of Environment, Republic of Haiti
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
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Haiti suffers from a serious deterioration of its natural environment and, in particular, from a heavy pressure on its natural resources. The reasons for this deterioration are multiple (poverty level, demographic pressure, agricultural techniques and insecurity regarding land tenure) and, therefore, go beyond the strict scope of energy. However, the wood-fuel consumption is one of the main factors of this deterioration. On a national scale, about 70 percent of the energy needs are met using firewood and charcoal. Although the local wood-fuel resources have been overexploited for more than 20 years, the price of wood-fuels does not reflect this scarcity phenomenon which constitutes a serious ecological threat at the countrywide level. The household energy sector remains, by far, the main consumer of wood-fuels, in as much as it absorbs 70 percent of the overall supply. However, this sector is characterized by very low efficiency in terms of use outputs.

Reducing Stress and Fuel Consumption Providing Road Information

Corcoba Magaña, Víctor; Muñoz Organero, Mario
Fonte: Springer International Publishing Switzerland Publicador: Springer International Publishing Switzerland
Tipo: info:eu-repo/semantics/acceptedVersion; info:eu-repo/semantics/bookPart; info:eu-repo/semantics/conferenceObject
Publicado em /05/2015 ENG
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In this paper, we propose a solution to reduce the stress level of the driver, minimize fuel consumption and improve safety. The system analyzes the driving and driver workload during the trip. If it discovers an area where the stress increases and the driving style is worse from the point of view of energy efficiency, a photo is taken and is saved along with its location in a shared database. On the other hand, the solution warns the user when is approaching a region where the driving is difficult (high fuel consumption and stress) using the shared database. In this case, the proposal shows on the screen of the mobile device the image captured previously of the area. The aim is that driver knows in advance the driving environment. Therefore, he or she may adjust the vehicle speed and the driver workload decreases. Data Envelopment Analysis is used to estimate the efficiency of driving and driver workload in each area. We employ this method because there is no preconceived form on the data in order to calculate the efficiency and stress level. A validation experiment has been conducted with 6 participants who made 96 driving tests in Spain. The system reduces the slowdowns (38 %), heart rate (4.70 %), and fuel consumption (12.41 %). The proposed solution is implemented on Android mobile devices and does not require the installation of infrastructure on the road. It can be installed on any model of vehicle.; The research leading to these results has received funding from the “HERMES- SMART DRIVER” project TIN2013-46801-C4-2-R within the Spanish “Plan Nacional de I + D+I” under the Spanish Ministerio de Economía y Competitividad and from the Spanish Ministerio de Economía y Competitividad funded projects (co-financed by the Fondo Europeo de Desarrollo Regional (FEDER)) IRENE (PT-2012-1036-370000)...

A Model for the Propulsion Fuel Consumption of an Aircraft Carrier

Modisette, Joel D.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: viii, 60 p.
EN_US
Relevância na Pesquisa
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Approved for public release; distribution is unlimited.; Speed and propulsion fuel consumption characteristics of United States aircraft carriers are modeled to determine how unpredictabilities in operational, engineering, and wartime environments affect the endurance capability of the ship. Research into the characteristics of steam propulsion plants on ships show that variability may exist in the amount of propulsion fuel required to support ship operation for a given period of time. Sources if this variability include the nonlinear transformation of operational data into fuel logistics data, the nearly deterministic engine reacting to inputs from a stochastic environment, and the effects of increased engine wear and ship's crew fatigue on engine performance. Implementations of this variation in a simulation indicate that conventional estimation techniques for fuel consumption may seriously overestimate the endurance capability if the aircraft carriers. The simulation results show that the distribution of endurance time resembles a normal distribution, with the estimated mean decreasing variance increasing as unpredictabilities in various environments are considered.; Lieutenant, United States Navy

Alternative practices to improve surface fleet fuel efficiency

Crawford, Dustin K.
Fonte: Monterey, California: Naval Postgraduate School Publicador: Monterey, California: Naval Postgraduate School
Tipo: Tese de Doutorado
Relevância na Pesquisa
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Approved for public release; distribution is unlimited; We explore the United StatesNavy's surface fleet policies and practices that, if changed, could provide significant fuel savings for fossil fuel ships. Recent and potential future budget cuts give fuel conservation and efficiency extreme importance. The policies and practices explored incur no overhead cost, and to reap the benefits of these changes, we simply need to prudently change in the way we operate. Conducting drift operations 10% of the nights while underway can save the Navy $14.1 million per year, and conducting single-generator operations 25% of the time underway can save $27.4 million per year. Removing the moving window requirement during a transit can reduce fuel consumption by as much as 21%. Utilizing the Transit Fuel Planner shows fuel savings as high as 19% during transits. Lowering the minimum fuel safety levels in 5th and 7th Fleets from 60% to 50% reduces fuel consumption for Military Sealift Command ships by $18.5 million per year. Changing or removing outdated policies and practices utilized by the surface fleet can save significant amounts of fuel, and therefore dollars, and can be done with the stroke of a pen.; Lieutenant, United States Navy

Development of cost estimating relationships for missile Engineering Manufacturing Development (EMD) costs and warship fuel consumption

Williams, Sandra A.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: 91 p.
EN_US
Relevância na Pesquisa
66.49%
Approved for public release; distribution is unlimited; The purpose of this thesis is to develop estimating relationships for missile Engineering and Manufacturing Development (EMD) costs and warship fuel consumption to aid the Naval Center for Cost Analysis (NCA) in performing independent cost estimates for new weapons programs. Standard factors, which represent the percent that each cost element is typically allocated from the program's total funding, are currently used to predict whether missile EMD costs are roughly right. For fuel consumption, estimating relationships have only been developed for existing individual ship types. None have been developed which use pooled ship types to estimate fuel consumption of new ship types. Regression analysis was used to develop estimating relationships based on physical and technical characteristics. The cost estimating relationships (CERs) developed to predict missile EMD costs explained only about 34 percent of the variance. Due to the low explanatory power, no significant physical or technical factors could be determined. Even though the results are not statistically significant, the associated coefficients of variation are lower than the standard factor coefficients of variation. An estimating relationship with high explanatory power was developed to predict fuel consumption for new warships. Three significant physical and performance factors were determined: steaming hours...

Reducing Haul Truck Fuel Consumption in Open Pit Mines by Strategic Changes to the Haulage Cycle

Vukovic, Vladimir
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
Relevância na Pesquisa
56.45%
The goals of minimizing emissions and lowering operating costs by monitoring and controlling fuel efficiency have been a growing concern in the mining and construction industries. The largest single contributor of energy consumption in an open pit mining operation is haul trucks. At Goldstrike Mine, haul trucks accounted for approximately 67% of fuel used in 2010. By examining haul trucks in their operating environment, strategic changes in critical parts of the truck cycles can result in fuel savings. This project was a subproject of the Mine Traffic Optimization (MTO) project and is funded by MITACS and Barrick Gold Corporation. One objective of the MTO project was to examine how mine traffic affects fuel efficiency. Certain components of the haulage profile result in inefficient use of fuel, which results in increased operating costs and a larger environmental footprint. Monitoring the trucks in real time allows for the examination of various ways to modify truck’s behaviours in order to improve fuel efficiency. One critical component of the haulage cycle is intersections. An analysis was performed to gain a better understanding of efficient intersection layouts and travel speeds. Cycle time analysis was conducted to ensure that alterations to the haulage cycle would result in minimal impact to the overall productivity of the mine. Modifications to operating practices and simple coding changes to the dispatching program suggest possibilities for potential fuel savings...

Cable length optimization for trawl fuel consumption reduction

KHALED, Ramez; PRIOUR, Daniel; BILLARD, Jean-Yves
Fonte: Elsevier Publicador: Elsevier
EN
Relevância na Pesquisa
66.28%
A numerical method for optimization of the cable lengths in trawls with respect to the ratio between the estimated trawl drag and the predicted catch efficiency is developed and applied. The trawl cables of interest are warps, bridles, headline and footrope. The optimization algorithm applies an ordered sequential process changing one cable length at the time. It is assumed in the predictions that the catch efficiency of the trawl is proportional with the trawl mouth area. In a case study optimizing a bottom trawl used on a research vessel by applying the new method it is predicted that it would be possible to reduce the ratio between trawl drag and catch efficiency by up to 46% by optimizing the cable lengths. Thus this would enable a considerable reduction in fuel consumption to catch a specific amount of fish. Moreover, we predict an increase in the value of the trawl mouth area leading to better catching efficiency without increase in otter door drag.; The authors would like to thank the European Fisheries Fund and the French Ministry of Agriculture and Fisheries for funding this field of research.

Estudo do impacto do pedágio no aumento do tempo de viagem, no consumo de combustível e na emissão de poluentes; Study the impact of toll increases in travel time, fuel consumption and pollutant emissions

Alvarenga, Gustavo Siqueira
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 02/06/2010 PT
Relevância na Pesquisa
56.49%
A praça de pedágio é uma intervenção instalada na rodovia que obriga à uma redução da velocidade de curso dos veículos. Essa alteração no perfil de velocidade aumenta o tempo de viagem, gera um consumo de combustível extra e a produção excedente de poluentes provenientes da queima desse combustível. Este trabalho analisou automóveis e caminhões cruzando a praça de pedágio Jacareí, localizada na Rodovia Presidente Dutra km 165. Mediu-se quanto tempo um veículo leva para efetuar o pagamento da tarifa e para percorrer a praça de pedágio. Foram feitas simulações do consumo de combustível dos caminhões cruzando a praça de pedágio. Foi utilizado um modelo matemático construído na plataforma Matlab Simulink. Baseou-se em testes em pista utilizando um GPS para aquisição dos dados de velocidade e espaço. Avaliou-se o consumo de combustível em função da carga transportada para três distintos perfis de velocidade de caminhões. Observou-se que o custo de uma transação no pedágio vai além do valor da tarifa. O custo com combustível da transação pode variar de R$0,52 a R$1,52, a depender da carga transportada pelo caminhão e do tamanho da fila de espera na cabine. A cobrança da tarifa quando efetuada com o veículo em movimento ameniza os impactos inerentes. A utilização do AVI como meio de pagamento da tarifa reduz em média 60% do tempo necessário para cruzar a praça...

Can UK passenger vehicles be designed to meet 2020 emissions targets? A novel methodology to forecast fuel consumption with uncertainty analysis.

Martin, Niall P. D.; Bishop, Justin D. K.; Choudhary, Ruchi; Boies, Adam M.
Fonte: Elsevier Publicador: Elsevier
Tipo: Article; published version
EN
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66.59%
This is the author accepted mansucript. The final version is available via Elsevier at http://dx.doi.org/10.1016/j.apenergy.2015.03.044; Vehicle manufacturers are required to reduce their European sales-weighted emissions to 95 g CO2/km by 2020, with the aim of reducing on-road fleet fuel consumption. Nevertheless, current fuel consumption models are not suited for the European market and are unable to account for uncertainties when used to forecast passenger vehicle energy-use. Therefore, a new methodology is detailed herein to quantify new car fleet fuel consumption based on vehicle design metrics. The New European Driving Cycle (NEDC) is shown to underestimate on-road fuel consumption in Spark (SI) and Compression Ignition (CI) vehicles by an average of 16% and 13%, respectively. A Bayesian fuel consumption model attributes these discrepancies to differences in rolling, frictional and aerodynamic resistances. Using projected inputs for engine size, vehicle mass, and compression ratio, the likely average 2020 on-road fuel consumption was estimated to be 7.6 L/100 km for SI and 6.4 L/100 km for CI vehicles. These compared to NEDC based estimates of 5.34 L/100 km (SI) and 4.28 L/100 km (CI), both of which exceeded mandatory 2020 fuel equivalent emissions standards by 30.2% and 18.9%...

Vehicle simulations of fuel economy for an automatic transmission and a ratio limited continuously variable transmission

Suthar, Hemant
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
56.46%
An automatic transmission (AT) of a vehicle was compared with a ratio limited Continuously Variable Transmission (CVT). Dynamic model of a passenger car was simulated to compare the overall efficiency of the vehicle equipped with these different types of transmissions. The overall efficiencies were calculated in terms of fuel consumption of the vehicle. The results are based on the Environmental Protection Agency's (EPA) city and highway driving cycles. A Modular approach is taken to model an existing vehicle. The complete model is subdivided into an engine model, road load model, throttle and brake pedal models, and a transmission model. The model is simulated in MATLAB/Simulink software. The automatic transmission model was then replaced by a CVT model and simulated under similar conditions to compare the overall gain in the fuel economy. The simulation results for the automatic transmission closely match with the data obtained from the EPA. The results for the ratio limited CVT indicate improvement in the fuel economy of the vehicle under both the urban and highway driving cycles.