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208 Uppsatser om Engine - Sida 4 av 14
Transportsfordon för rullstolsburna
A vehicle that carries a person sitting in a wheelchair has been rebuilt. The original vehicle was provided with a petrol Engine, hydrostatic drive and a mechanical steering rod, making it noisy and hard to maneuver. The purpose with this project was to convert the vehicle to make it more environmental and easier to drive.A new design has been proposed where an electrical drive has replaced the noisy combustion Engine and an electrical motor with joystick control has replaced the manual steering.The project was divided into two parts. One mechanical part where the construction of the drive and steering were to be decided. The other part involved programming the microprocessor and implementation of all the necessary electrical for the control system of the vehicle.
CFD simulering av en fyrtakts Otto motorcykel motor
This thesis deals with the numerical 3D simulation of a four stroke, spark-ignited, internalcombustion Engine, which is mounted on a high performance motorcycle. The work, carried outin collaboration with Politecnico di Milano and MV Agusta, focuses on the simulation of theintake, compression and expansion stroke, including combustion simulation, using an opensource CFD code.Simulation of internal combustion Engines offers a great challenge in the field of CFD research.Moving boundaries of the solution domain, caused by the motion of the piston and valves, leadsto deformation of the computational grid, with decreasing quality of the solution as result. Basedon this, a previously developed mesh motion strategy was employed where a number of meshesare used to cover the whole simulation cycle. Within each mesh interval the internal cell pointsof the mesh are moved to account for the boundary motion of the piston and valves. This strategywas previously applied to simplified geometries as well as real Engine geometries.
VVA-strategier för avgastemperaturhöjning på en HD-Dieselmotor
Regulations on the exhaust emissions of HD-diesel Engines are becoming more and more stringent, and therefore, emission after-treatment systems are commonly used. These systems rely on catalytic conversion of NOx,CO , and HC emissions, and are thus dependant on temperature. At low load of the Engine, exhaust temperatures are not sufficient for the after-treatment components. Therefore, means to increase the exhaust temperature while maintaining low emissions and fuel consumption are needed.The focus of this project has been to develop strategies for the lift profiles of exhaust and intake valves in the Engine, with the goal to raise exhaust temperature in combination with low emissions and fuel consumption. The strategies have been tested in a single-cylinder research Engine equipped with a hydraulic variable valve actuation system.
Att göra eller inte göra : Hur kontroll och nyfikenhet påverkar regelverket på Facebook
This paper is a literature study on search Engine optimization (SEO) considering the leader of the search Engine market: Google. There´s an introductory background description of Google and its methods of crawling the Internet and indexing the web pages, along with a brief review of the famous PageRank algorithm. The purpose of this paper is to describe the major important methods for improved rankings on Google´s result lists. These methods could be categorized as on-page methods tied to the website to be optimized or off-page methods that are external to the website such as link development. Furthermore the most common unethical methods are described, known as ?black hat?, which is the secondary purpose of the text.
Reglerstrategi för fria ventiler : ? Utveckling av en fyrtakts förbränningsmodell för att prediktera optimala ventilinställningar
As emission legislations across the world continuously pushes Engine development forward,Engineers constantly need to come up with and implement fuel saving technologies. During thelast decade, variable cam phasing has become a popular solution to increase gas exchangeefficiency. This configuration is typically mechanically constrained by camshaft limitations, anda solution to circumvent this problem would be to use a different valve actuation principle.One example of this is to use pressurized air controlled by electrical solenoids. Such a systemhas been developed byCargine Engineering and this provides the starting point for this work. Tobe able to operate the valvetrain on an actual Engine, a control system is needed.
Akademiska söktjänster: En jämförande studie av Google Scholar, MEDLINE och Web of Science
The purpose of this paper is to compare the three search Engines Web of Science, Google Scholar and MEDLINE in regards of recovery efficiency and the overlap of relevant documents when it comes to information searching for academic purposes. Furthermore, it raises the question whether freely available search Engines and licensed search Engines are interchangeable with each other. The empirical data in this study were collected through searches conducted in the three search Engines Web of Science, Google Scholar and MEDLINE. Twenty search queries were used and the first twenty retrieved documents for each query were examined for relevance using previously designed criteria. The documents were scored by a binary relevancy scale and thereafter a precision value for each search Engine was calculated.
Beslutsmodell för inköp och lagerhållning av motorer i ett produktionssystem : En fallstudie på Sandvik
AbstractIt is important to choose which spare parts to keep in stock. With the right spareparts in stock the costs for inventory and production loss will decrease. Cavalieri et al. (2008) highlights that the balance between inventory cost and production loss is underestimated. It affects the company and must be considered before decision on purchase.The problem with spare Engines is that they are all more or less critical for the production. That can be a reason for why no previous research targeting Engines and classification of with Engine should be kept in stock has been found.
VÄRDEFLÖDESANALYS AV PW1000G 30k TEC
The thesis work has been carried out at Volvo Aero Corporation (VAC) in Trollhättan. VAC has entered a partnership as developing and producing partner with Engine manufacturer Pratt & Whitney and is currently at the starting phase of producing the turbine rear frame (TEC) to the Engine PW1000.The purpose of this study was to create a report on process level that describes the conditions and the potential with PW1000 TEC to reach the product cost calculation taking into account lead times and describe alternative method solutions.The report describes a comparison between the present flow (2012), a flow based on product cost calculation (2016) and a potential flow (2016). The work has mainly been based on acquiring the knowledge and information available to inspect the present flow; this has been done by workshop observations, meetings and gathering of the information that is available on the work site for the PW1000 TEC.The information obtained has been merged into an Excel document, called Roadmap. It serves as a roadmap with current situation as the start and the potential flow for 2016 as the goal. With the roadmap as a tool, assumptions have been taken considering the flow and how it will change, where processes have been eliminated, reduced or marked as a problem..
Google Bilders användbarhet : Gränssnitt, sökfunktioner och återvinning
This essay explores to what extent the Swedish language version of Google Images meets the usability requirements of average everyday users. Previously published studies on user behaviour and users? interface and search option preferences define the usability requirements, which are matched against Google Images? actual interface and search options. The retrieval method of Google Images is also briefly discussed, and users? opinions about Google Images too, as they come across in the previously published user studies.The findings are that Google Images lack some of the things that users ask for, but it still seems to be the most used image search Engine among average internet users and more appreciated than other search Engines.
Modellbaserad prediktiv reglering av en dieselmotor med variabel geometriturbin och återcirkulering av avgaser
Control of a diesel Engine equipped with Variable Geometry Turbine (VGT) and Exhaust Gas Recirculation (EGR) requires a multivariable control method. One problem is that the Engine system is non-linear. Furthermore there are strong cross-connections between inputs and outputs and the inputs have alsoboundaries. To be able to manage these control problems, MPC has been used that is a multivariable method. The MPC-controller consists of an optimization problem and therefore MPC can find the optimum control signals in an easy way.
Diesel Dubbelbränsle Teknologi
The work covered in this report includes a literature study of the diesel dual fuel technology(hereinafter referred to as DDF). The literature study covers earlier work that has been doneregarding the use of compressed natural gas (CNG) and diesel in a DDF system. Moreover a onecylinder research diesel Engine was fitted with a CNG fuel system for experimental testing. Theinstallation of the Engine and the test cell is described. Results from the tests are presentedcovering emissions, heat release and pressure traces from the DDF-concept.During the literature study it was found that most research was related to heavy duty dieselEngines.
Att göra det osynliga synligt : sökmotoroptimering (SEO) av en webbsajt
A webpage can be perfectly usable but if users are unable to find the webpage it will remain unused. Nine out of ten Swedes use a search Engine and the most popular one is Google, amongst other search Engines. In this report I seek to answer which ranking factors that should be included in an SEO-audit of an existing webpage and also how to optimize a webpage for search Engines. Applying the method heuristic evaluation normally used to discover usability issues in an existing interface, on TT News Agency?s campaign site I found issues having a negative impact on the visibility in Search Engines Page Results.
Biogas till kraftvärme på Wapnö : en projektanalys utifrån ett företagsekonomiskt perspektiv
Biogas is a gaseous fuel, rich in methane, produced through a biological route in an anaerobic digester. A gas Engine generates combined heat and power, which can be used at the farm to reduce energy cost. The process also generates a digestate, with better utilization of nutrient compared to cattle manure.
The aim of this study is to analyze the profitability of a farm-scale biogas plant for combined heat and power (CHP) at Wapnö. Wapnö is an agriculture company located in the southern part of Sweden.
Beräkning av värmeförluster och energieffektivisering av elbussar
The ?civilized? world is in need of fossil fuel in order to function. Hybricon AB is a company in Umeå that is developing a technology that hopefully can reduce parts of this need. They are currently testing their two electrical busses (with Hybrid backup) in city traffic on the roads of Umeå in cooperation with the county of Umeå. The busses are originally diesel-busses, but the diesel motor has been replaced with two electrical hub-motors with a power of 145 kW each that are powered by batteries.The batteries are charged at the end station after each route. In case the batteries should run low on capacity during driving, they can be recharged by the so called genset.
Optimerande av gasanläggning - genom värmeåtervinning och förlustreducering. Gässlösa Reningsverk
The municipality, of Gatukontoret in Local government of Borås has in the long run, a required need to look after the current heating devices (the gas production plant) in sewage treatment plant, called Gässlösa. The practical work of the examination is about, trying to find a better way to take care of the current heat recovery. That may be one way or another, rather easy to implement in the existent construction.Through the work to increase the efficiency of the gas Engine, implement of some external cooling system by heating exchange device. That gives an opportunity to heat (primary) the digester, (but even all internal public areas) with its own superfluous heating.The report shows that if the management group may invest 422 704 crown to implement a heat exchanging device, it gives more space to reduce the need to buy expensive external energy. Gatukontoret´s pay off time, for buying machines, is 20 years, with reservation to calculate with 4 percent internal interest, leads to the yearly mount of 31103 crowns.If Gässlösa increases the gas Engine time in (effective) duty approximately (correspondingly) 48 hours a month the entire investment will generate a profit in January in year seven after the implementations.