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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.
41

Bränsle-ekonomisk studie för framdriftsmotorn ombord på M/T Ramona / Fuel economic study for the propulsion engine on board M/T Ramona

Sörensson, Oscar January 2021 (has links)
Detta är en studie med syfte att visa vid vilka driftsförhållanden fartyget M/T Ramonas framdriftsmotor driver fartyget som mest bränsleeffektivt och på så sätt även med minst miljöpåverkan genom avgasutsläpp (Havsmiljöinstitutet, 2017). Dessa två driftsförhållande är lastad samt olastad kondition. Fartyget har under studien körts med så kallat combinator mode och har haft sin strömförsörjning via en axelgenerator. Resultatet baseras på 12 veckors datainsamling.Efter att all data samlats in och uträkningar analyserats, har ett resultat per kondition kunnat presenteras med hjälp utav figurer. Den slutsats som kunde dras var att, vid lastad kondition driver framdriftsmotorn fartyget som mest effektivt vid en belastning på 46 till 48 procent och en hastighet på 10.5 knop. Dock finns en felmarginal då tester inte tilläts vid lägre belastningar på framdriftsmotorn vid tiden för studien. Slutsatsen som drogs för den olastade konditionen var att framdriftsmotorn driver fartyget som mest bränsleeffektivt vid en belastning på 34 till 38 procent och en hastighet på 8.3 knop. / This is a study aimed at showing the operating conditions at which the M/T Ramonas propulsion engine is operated most fuel efficient and thus also with the least environmental impact through exhaust emissions (Havsmiljöinstitutet, 2017). These two operating conditions are loaded and unloaded condition. During the study, the ship has been run in so-called combinator mode and has had its electricity generated via a shaft generator. The result is based on 12 weeks of data collection. After all the data has been collected and calculations has been analyzed, a result per condition has been presented using figures. The conclusion that could be drawn was that, at loaded condition, the propulsion engine is driven most fuel efficiently at a load of 46 to 48 percent and at a speed of 10.5 knots. However, there is a margin of error as tests were not allowed at lower loads on the propulsion engine at the time of the study. The conclusion reached for the unloaded condition was that the propulsion engine is driven most fuel-efficient at a load of 34 to 38 percent and at a speed of 8.3 knots.
42

Torque vectoring to maximize straight-line efficiency in an all-electric vehicle with independent rear motor control

Brown, William Blake 10 December 2021 (has links) (PDF)
BEVs are a critical pathway towards achieving energy independence and meeting greenhouse and pollutant gas reduction goals in the current and future transportation sector [1]. Automotive manufacturers are increasingly investing in the refinement of electric vehicles as they are becoming an increasingly popular response to the global need for reduced transportation emissions. Therefore, there is a desire to extract the most fuel economy from a vehicle as possible. Some areas that manufacturers spend much effort on include minimizing the vehicle’s mass, body drag coefficient, and drag within the powertrain. When these values are defined or unchangeable, interest is driven to other areas such as investigating the control strategy of the powertrain. If two or more electric motors are present in an electric vehicle, Torque Vectoring (TV) strategies are an option to further increase the fuel economy of electric vehicles. Most of the torque vectoring strategies in literature focus exclusively on enhancing the vehicle stability and dynamics with few approaches that consider efficiency or energy consumption. The limited research on TV that addresses system efficiency have been done on a small number of vehicle architectures, such as four independent motors, and are distributing torque front/rear instead of left/right which would not induce any yaw moment. The proposed research aims to address these deficiencies in the current literature. First, by implementing an efficiency-optimized TV strategy for a rear-wheel drive, dual-motor vehicle under straight-line driving as would be experienced in during the EPA drive cycle tests. Second, by characterizing the yaw moment and implementing strategies to mitigate any undesired yaw motion. The application of the proposed research directly impacts dual-motor architectures in a way that improves overall efficiency which also drives an increase in fuel economy. Increased fuel economy increases the range of electric vehicles and reduces the energy demand from an electrical source that may be of non-renewable origin such as coal.
43

新方式ハイブリッドシステム搭載長距離貨物トラックの燃料消費率改善に関する研究 / シンホウシキ ハイブリッド システム トウサイ チョウキョリ カモツ トラック ノ ネンリョウ ショウヒリツ カイゼン ニカンスル ケンキュウ

奥井 伸宜, Nobunori Okui 13 September 2018 (has links)
車両の電動化(ハイブリッド化)と内燃機関システムの電動化を最適に組み合わせた技術と、それらを効果的に稼働させるハイブリッド制御ロジックを適用した新方式大型ハイブリッドトラックを提案した。長距離貨物輸送時の燃料消費率の改善に対し効果があることを明らかとした。同時に、従来大型トラックに対し、荷室搭載性の確保や車両コストの抑制が可能となることが分かり、実用性の面でも優位性があることを示した。 / 博士(工学) / Doctor of Philosophy in Engineering / 同志社大学 / Doshisha University
44

Simulation Studies of Impact of Heavy-Duty Vehicle Platoons on Road Traffic and Fuel Consumption

Johansson, Ingrid January 2018 (has links)
The demand for road freight transport continues to grow with the growing economy, resulting in increased fossil fuel consumption and emissions. At the same time, the fossil fuel use needs to decrease substantially to counteract the ongoing global warming. One way to reduce fuel consumption is to utilize emerging intelligent transport system (ITS) technologies and introduce heavy-duty vehicle (HDV) platooning, i.e. HDVs driving with small inter-vehicle gaps enabled by the use of sensors and controllers. It is of importance for transport authorities and industries to investigate the effects of introducing HDV platooning. Previous studies have investigated the potential benefits, but the effects in real traffic, both for the platoons and for the surrounding vehicles, have barely been explored. To further utilize ITS and optimize the platoons, information about the traffic situation ahead can be used to optimize the vehicle trajectories for the platoons. Paper I presents a dynamic programming-based optimal speed control including information of the traffic situation ahead. The optimal control is applied to HDV platoons in a deceleration case and the potential fuel consumption reduction is evaluated by a microscopic traffic simulation study with HDV platoons driving in real traffic conditions. The effects for the surrounding traffic are also analysed. Paper II and Paper III present a simulation platform to assess the effects of HDV platooning in real traffic conditions. Through simulation studies, the potential fuel consumption reduction by adopting HDV platooning on a real highway stretch is evaluated, and the effects for the other vehicles in the network are investigated. / Efterfrågan på godstransporter på väg fortsätter att öka i takt med den växande ekonomin, vilket resulterar i ökad förbrukning av fossila bränslen och ökade utsläpp. Samtidigt behöver användandet av fossila bränslen minska för att motverka den pågående globala uppvärmningen. Ett sätt för att minska bränsleförbrukningen är att utnyttja den teknik kring intelligenta transportsystem som är under utveckling och introducera lastbilskonvojer, det vill säga lastbilar som använder sensorer och regulatorer för att kunna köra med korta avstånd mellan sig. För transportföretag och -myndigheter är det viktigt att undersöka effekterna av att införa lastbilskonvojkörning. Tidigare studier har undersökt de möjliga fördelarna, men effekterna vid körning i trafik, både för konvojerna och för omgivande fordon, är outforskade. För att ytterligare utnyttja intelligenta transportsystem och optimera konvojerna kan information om trafiksituationen längre fram på vägen användas för att optimera konvojernas körning. Artikel I presenterar en optimal hastighetsregulator baserad på dynamisk programmering och som inkluderar information om trafiksituationen längre fram. Den optimala regulatorn appliceras på lastbilskonvojer under ett inbromsningsscenario och den potentiella minskningen i bränsleförbrukning utvärderas genom en mikroskopisk trafiksimuleringsstudie där lastbilskonvojerna kör i verkliga trafikförhållanden. Effekterna för omgivande fordon är också analyserade.Artikel II och artikel III presenterar en simuleringsplattform för att utvärdera effekterna av lastbilskonvojkörning i verkliga trafikförhållanden. Genom simuleringsstudier analyseras den potentiella bränsleförbrukningsminskningen då lastbilskonvojer körs på en verklig motorvägssträcka och effekterna för de övriga fordonen på vägen undersöks. / <p>QC 20180516</p>
45

Design of a novel rotary compact power pack for the series hybrid electric vehicle. Design and simulation of a compact power pack consisting of a novel rotary engine and outer rotor induction machine for the series hybrid electric vehicle powertrain.

Amirian, Hossein January 2010 (has links)
Hybrid electric vehicles significantly reduce exhaust emissions and increase fuel economy. Power packs are the most fundamental components in a series powertrain configuration of a hybrid vehicle, which produce the necessary power to run the vehicle. The aim of this project is to design a compact power pack for a series hybrid vehicle, using virtual prototyping. The hybrid electric vehicle characteristics and configurations are analysed, followed by an explanation of the principles of induction machines. A new type of rotary induction machine with an outer rotor construction is designed to be coupled with the novel rotary internal combustion engine with rotating crankcase in order to form the compact power unit for the hybrid vehicle. The starting and generation performance of the designed machine is analysed by an electric machine simulator, called JMAG. ADVISOR software is studied and utilised to simulate the overall vehicle performance, employing different categories of power packs in the powertrain. Results show that the proposed compact power pack has the best performance in terms of fuel economy, emissions and battery charging compared to the existing power unit options. Over the city cycle, fuel economy is increased by up to 47 % with emission reduced by up to 36 % and over the highway cycle, fuel economy is increased by up to 69 % with emission reduced by up to 42 %.
46

Analytical design of a parallel hybrid electric powertrain for sports utility vehicles and heavy trucks

Madireddy, Madhava Rao January 2003 (has links)
No description available.
47

Vehicle powertrain model to predict energy consumption for ecorouting purposes

Tamaro, Courtney Alex 27 June 2016 (has links)
The automotive industry is facing some of the most difficult design challenges in industry history. Developing innovative methods to reduce fossil fuel dependence is imperative for maintaining compliance with government regulations and consumer demand. In addition to powertrain design, route selection contributes to vehicle environmental impact. The objective of this thesis is to develop a methodology for evaluating the energy consumption of each route option for a specific vehicle. A 'backwards' energy tracking method determines tractive demand at the wheels from route requirements and vehicle characteristics. Next, this method tracks energy quantities at each powertrain component. Each component model is scalable such that different vehicle powertrains may be approximated. Using an 'ecorouting' process, the most ideal route is selected by weighting relative total energy consumption and travel time. Only limited powertrain characteristics are publicly available. As the future goal of this project is to apply the model to many vehicle powertrain types, the powertrain model must be reasonably accurate with minimal vehicle powertrain characteristics. Future work expands this model to constantly re-evaluate energy consumption with real-time traffic and terrain information. While ecorouting has been applied to conventional vehicles in many publications, electrified vehicles are less studied. Hybrid vehicles are particularly complicated to model due to additional components, systems, and operation modes. This methodology has been validated to represent conventional, battery electric, and parallel hybrid electric vehicles. A sensitivity study demonstrates that the model is capable of differentiating powertrains with different parameters and routes with different characteristics. / Master of Science
48

Common Rail - En bränslebesparingsstudie : – En utvärdering av ett nyinstallerat bränsleinsprutningssystem på isbrytaren Ymer / Common Rail - A fuel saving study : - An evaluation of a newly installed fuel injection system on the icebreaker Ymer

Andrén, Filip, Borgström, Olav January 2016 (has links)
Följande studie är gjord på uppdrag av Sjöfartsverket. I studien undersöktes hur en installation av ett Common Rail-system ombord på isbrytaren Ymer påverkat bränsleförbrukningen samt utsläppen av kväveoxider. Rådata som loggats ombord på Ymer har analyserat och bearbetat. Material och information från tillverkare, besättning samt teknisk chef på Sjöfartsverket, Albert Hagander har använts under studien. Tillsammans med uppmätta mätdata och tidigare gjord litteraturstudie stöds resultaten i studien. Det är ingen slump att system av Common Rail-typ redan är tillämpat inom de flesta branscher så som transport, personbilsindustri och jordbruk. Huvudsyftet med Common Rail är att minska bränsleåtgången samt minska utsläppen genom en renare och mer effektiv förbränning av bränslet.  Huvudsakligen undersöktes hur det nyinstallerade systemet påverkat bränsleförbrukningen och hur bränslebesparingen varierar med belastningen av maskinen. Vidare granskades hur utsläppen av kvävedioxider påverkats efter installationen. Problematiken med ökad NOx-produktion till följd av en högre förbränningstemperatur som Common Railsystemet medför diskuteras i rapporten. De resultat vi kommit fram till att en bränslebesparing kan göras ombord på Ymer genom att ersätta det gamla bränslesystemet med ett bränslesystem av Common Rail-typ. Vidare har installationen medfört andra förbättringar så som fartygsmaskinens reaktion på de många lastväxlingar som förekommer under isbrytning. / The following study has been carried out on behalf of Sjöfartsverket. The study examines how the installation of a common rail system on board the icebreaker Ymer affected fuel consumption and emissions of nitrogen oxides. The raw data logged on board Ymer was analyzed and processed. Materials and information from manufacturers, crew and the technical manager at the Swedish Maritime Administration, Albert Hagander have been used during the study. Together with measured data and previously made research study the findings of the study are supported. It is no coincidence that the system of the common rail type is already applied in most industries such as transport, car industry and agriculture. The main purpose of the Common Rail is to reduce fuel consumption and reduce emissions through cleaner and more efficient combustion of the fuel. We primarily examined how the newly installed system affected fuel consumption and the fuel savings will vary with the load of the machine. Furthermore, we examined how emissions of nitrogen oxides were affected after installation. The problem of increased NOx production due to a higher combustion temperature as the common rail system entails are discussed in the report. The result that was concluded was that fuel savings can be made on board Ymer by replacing the old fuel system with a common rail fuel type. Furthermore, the installation has brought other improvements such as ship machine's reaction to the many load changes that occur during icebreaking.
49

Optimal vehicle structural design for weight reduction using iterative finite element analysis

Tebby, Steven 01 June 2012 (has links)
The design and analysis of an automotive structure is an important stage of the vehicle design process. The structural characteristics have significant impact on the vehicle performance. During the design process it is necessary to have knowledge about the structural characteristics; however in the preliminary design stages detailed information about the structure is not available. During this period of the design process the structure is often simplified to a representative model that can be analyzed and used as the input for the detailed design process. A vehicle model is developed based on the space frame structures where the frame is the load carrying portion of the structure. Preliminary design analysis is conducted using a static load condition applied to the vehicle as pure bending and pure torsion. The deflections of the vehicle based on these loading conditions are determined using the finite element method which has been implemented in developed software. The structural response, measured as the bending and torsion stiffness, is used to evaluate the structural design. An optimization program is implemented to improve the structural design with the goal of reducing weight while increasing stiffness. Following optimization the model is completed by estimating suitable plate thicknesses using a method of substructure analysis. The output of this process will be an optimized structural model with low weight and high stiffness that is ready for detailed design. / UOIT
50

Hybrid powertrain performance analysis for naval and commercial ocean-going vessels

Gully, Benjamin Houston 11 October 2012 (has links)
The need for a reduced dependence on fossil fuels is motivated by a wide range of factors: from increasing fuel costs, to national security implications of supply, to rising concern for environmental impact. Although much focus is given to terrestrial systems, over 90% of the world's freight is transported by ship. Likewise, naval warfighting systems are critical in supporting U.S. national interests abroad. Yet the vast majority of these vessels rely on fossil fuels for operation. The results of this thesis illustrate a common theme that hybrid mechanical-electrical marine propulsion systems produce substantially better fuel efficiency than other technologies that are typically emphasized to reduce fuel consumption. Naval and commercial powertrains in the 60-70 MW range are shown to benefit substantially from the utilization of mechanical drive for high speed propulsion; complemented by an efficient electric drive system for low speed operations. This hybrid architecture proves to be able to best meet the wide range of performance requirements for each of these systems, while also being the most easily integrated technology option. Naval analyses evaluate powertrain options for the DDG-51 Flight III. Simulation results using actual operational profile data show a CODLAG system produces a net fuel savings of up to 12% more than a comparable all-electric system, corresponding to a savings of 37% relative the existing DDG-51 powertrain. These results prove that a mechanical linkage for the main propulsion engine greatly reduces fuel consumption and that for power generation systems requiring redundancy, diesel generators represent a vastly superior option to gas turbines. For the commercial application it is shown that an augmented PTO/PTI hybrid system can better reduce cruise fuel consumption than modern sail systems, while also producing significant benefit with regard to CO2 emissions. In addition, using such a shaft mounted hybrid system for low speed electric drive in ports reduces NOx emissions by 29-43%, while CO is reduced 57-66% and PM may be reduced up to 25%, depending on the specific operating mode. As an added benefit, fuel consumption rates under these conditions are reduced 20-29%. / text

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