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367 Uppsatser om Fuel ethanol - Sida 18 av 25
Utveckling av en Multi-Zonsmodell för NOx Bildning i Diesel Motorer
This thesis work is the last part of the Master of Science education inmechanical engineering at KTH, Stockholm.The aim of this project was the development of a Multi-zone modelfor NOxformation in Diesel engines. Because of the stringent emissionlegislations, great effort is made to decrease the fuel consumption and theharmful emissions of internal combustion engines. Computer simulationsplay a decisive role in this context because they substitute the expensiveand time-consuming laboratory tests.The model is based on a multi-zone approach and uses the wellknownExtended Zeldovich Mechanism which gives a relation to calculatethe NO formation rate using the concentration of different gas speciesinvolved in the process.All the most important phenomena involved in the Diesel combustionhave been modelled. A special attention is then paid to the equilibriumconcentration calculation; this is a significant part of the model whichstrongly influences the following steps.A Simulink model has also been developed. This second version isbased on the previous model and it is made especially to allow theconnection with other external softwares, GT-power in this case.
Uppdatering av båtnadskalkyl med hänsyn till nya faktorer :
Sweden have 419 000 km road in the country and about half of these roads is forestroads. The forest road net most important mission is to make it possible to deliver wood from the forest to the industries. With a raw material that is spread over a large area the road network is important. Each year has the forest road network been extended with about 1 700 km new roads. To decide if a new road is to be built different forest road cost estimation models has been used.
Årlig gödsling med NPK bäst för gröda, miljö och ekonomi
Yesterdays common fertilizing strategy was to apply phosphor (P) and potassium (K) in thefall a few times in the crop rotation. In the spring only nitrogen (N) was applied. Recent trialsand studies has shown that this strategy, N+P/PK, is ineffective compared with the systemwhere NPK is spread every year in the spring. The strategy with annual NPK-fertilizer in thespring has proven to be better for the crop, the environment and the farmers economy.In the NPK-system the crop responds with higher yields and better quality, especially in thespring cereals. This is mainly because of an interaction between the different nutrients in thefertilizer.
Elektrisk servostyrning för fyrhjulingar
This thesis is a feasibility study for a future product development project. The purpose ofthis project is to evaluate the possibilities and difficulties associated with the design of anelectric power assist servo for all terrain vehicles (ATVs). The project has been carriedout in collaboration with Nira Control AB. Nira designs and manufactures electric andelectro mechanic products mainly for the motor sport market segment.Nira Control AB is developing a fuel injection system for a new line of large ATVs oncommission. To be able to compete with manufacturers like Yamaha and Honda thecommissioner should be able to offer optional power assist steering.
Energikrav i upphandling av bygg- och anläggningsprojekt
The building and plant sectors represent a large part of Sweden?s energy use. Putting energy requirements in public procurement as a tool for reducing energy consumption in the building and plant sectors is therefor an opportunity that operators can take advantage of. The aim of this thesis was to map the energy requirements in procurement that operators in the public sector use today in building and plant projects. The analysis was made with respect to if the energy requirements corresponded to the parts with large energy use in building and plant projects and also in which way energy requirements in procurement are written in the contract.
H2 För racing
AbstractMotor sports have been around as long as motor vehicles have been. Sports are often seen as costly polluter but in the same time the motor sports have encourages a large part of development, both for vehicles and other industries. Inventions like rear mirror and ABS brakes come from motor sports. One way to once again drive development forward while making motor sports carbon-neutral is to run the race cars on hydrogen. In this thesis, the goal is to convert a spark ignition engine for hydrogen operation.
Finansiärer ur ett hållbarhetsperspektiv : En aktörsstudie av Europeiska Investeringsbanken, Nordiska Investeringsbanken och Svensk Exportkredit
Today a major part of the energy produced steams from fossil fuels, finite resources, and a change towards an energy sector based on renewable energy is necessary. Sweden is one of the leading countries with regards to investments in renewable energy but most other countries have a long way to go. This makes it interesting in developing renewable energy projects in new markets in countries like Poland where still a lot of fossil fuel is used. Large infrastructure development projects are very costly and therefore external investors needs to be involved. The investors play an important role in changing the usage of fossil fuels towards renewable energy sources.
Vinterträdgårdar ur ett byggperspektiv : En undersökning om byggandet av vinterträdgårdar
The purpose of this of this essay is to explore the construction of a conservatory that is livable allyear around. When you build a conservatory there are several factors that need to be regardedthat usually are of no importance when you build a regular conservatory. The glassed facadeneeds to have a very good U-value and all the parts of the facade need to be isolated and theconstruction needs to prevent thermal bridges.In this essay we will start by looking at the shape of the conservatory. Due to the façade consistsof glass the conservatory will need to have a good ratio between the area and the façade so thatthe heat losses will be at a minimum. However, due to the fact that one of the sides of the façadeis connected to the warm house, you quickly realize that the shape of the conservatory is of noimportance.There are two common ways to build a foundation for a conservatory, a molded concretefoundation and isolated wooden beams.
Stråkröjning och skogsbränsleuttag i unga granbestånd jämfört med konventionella metoder : Två fältstudier vid Asa försökspark
Den här uppsatsen grundar sig på två fältstudier i nyutlagda demonstrationsförsök på Asa försökspark som ska användas i utbildningssyfte. Studie 1 bestod av försöksytor i ett 13 år gammalt bestånd som röjts till samma röjningsförband men med tre skilda metoder; motormanuell selektiv röjning, maskinell stråkröjning och som en kombination av bägge metoderna. Syftet var att beskriva det nuvarande tillståndet, simulera fram prognoser för beståndsutvecklingen och beräkna dess ekonomiska konsekvenser fram till och med första gallring och jämföra de olika metoderna med varandra. Studie 2 bestod av försöksytor i ett 23 år gammalt eftersatt bestånd där fyra olika åtgärder testades; ingen röjning innan gallring, underröjning i samband med gallring, sen röjning och skogsbränsleuttag. Syftet var även här att jämföra de olika metoderna med varandra genom beskrivning av det nuvarande tillståndet, göra prognoser för beståndsutvecklingen och beräkna dess ekonomiska konsekvenser vid första gallring och i den här studien även fram till och med den andra gallringen.
Rederiers hantering av nya miljökrav : En studie om Birka Cruises, Tallink Silja och Viking Lines arbete med ekonomisk och miljömässig hållbar utveckling
The purpose of this study is to examine how Viking Line, Tallink Silja and Birka Cruises work with economic and environmental sustainability, and also to see how they work with new environmental legislations. In 2015 a new environmental legislation will be introduced, by the name Sulphur directive. The Sulphur directive entails a reduction in Sulphur dioxide emissions from ships where the emissions cannot exceed 0,1 percent. There are three alternatives to achieve the new environmental legislation, the use of Marine Gas Oil, LNG or scrubbers. All three alternatives will lead to increasing costs for the shipping industry.
Modellbaserad temperaturregleringav partikelfiltrets regenereringsprocess
Due to increasing regulations regarding new diesel vehicles particulate matteremissions the new Scania truck, Scania Euro 6, has been equipped with a particulatefilter. This component effectively stores the particles in the exhaust gas but must becleaned in order to prevent itself from clogging. The filter is cleaned through aprocess named regeneration which is a thermodynamic process in which thetemperature of the filter is raised through fuel supplied to the exhaust gas.The purpose of this thesis is to contribute to the development of improved controlstrategies of the temperature during the regeneration process through thedevelopment of model-based controllers. These controllers are designed in order tohave good performance in stationary as well as automatic regeneration.In order to develop these model-based controllers a model of the system isconstructed. The model is described as a linear thermodynamic grey-box model withflow varying parameters, showing good results in validation.The model provides a simulation environment during the controller design, which isfocused around the development of linear regulators with the exhaust gas mass flowas a scheduling variable whose size determines controllers? mode of operation.
Elbilen på väg mot 2030 : Handlingsplan för införande av elbilen i Sverige
The aim of this study is to examine possibilities and barriers for an introduction of electric vehicles in Sweden. The study has an interdisciplinary approach and thoroughly examines the essential topics which influence the future of the electric vehicle. The study reaches from answering the question on why electric vehicles lost the game to petrol cars in the early 20th century, to sketch how the difference in total cost of ownership will be between electric vehicles and petrol cars for the coming 20 years. Apart from these subjects the main topics of the study are today?s and tomorrow?s situation regarding technology, charging, fuel, market and economic incentives from an electric vehicle perspective.
Aktiv ventilstyrning
To achieve an optimal combustion, an even air/fuel ratio in the combustion chamber is required. An optimal combustion leads to reduced amount of emissions due to a more complete combustion, which is an important matter because of the sharpened environmental laws. This can be attained, among other things, by applying entirely variable cam times. To optimize the engines efficiency and its emissions at all workloads and speeds, an active valve control can be applied. This means that the intake and exhaust-valves can be opened and closed at any time, independent of the crankshaft position.
Konsekvensanalys för ?worst case scenario? på Mälarhamnar AB Västerås
AbstractConsequence analysis ?worst case scenario? at Mälarhamnar AB VästeråsDavid DotzskyMälarhamnar AB is a company that handle large amounts of oil, diesel, biofuel and petrol. That result in a lot of work to prevent accidents. The risks with modern technology is very small but it can?t be eliminated.
Småskaligt vattenkraftverk i Nyköpingsån
Interest in alternative energies is high in Sweden today, particularly in the agricultural sector. According to the Swedish lantbruksbarometern (2009), almost all respondents consider the use of some form of alternative energy from the farm. While interest in alternative energies is large, attention to the alternative energy straw has fallen and is almost nowhere mentioned in the literature today. Three years ago, in the Lantbruksbarometern nearly 44% of the farmers would be willing to invest in straw as heating system on the farm. How do the farmers decide to invest in alternative energies? With this information a problem is presented for this paper.