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31 Uppsatser om Rotor - Sida 2 av 3

Påverkan av skuggor från vindkraftverk

To get rid of our dependence on fossil fuels we need to make use of renewable energy sources like wind power to a greater extent. Even though wind power is a renewable energy source it can still cause some problems for the close environment. One of the problems is shadow flickering. When the sun is low and the wind blows in a direction so that the Rotor blades are positioned at right angles to the sunbeams and ?cut? the sunbeams off.

Skarven : ? Produktutveckling av en oljedimavskiljare

This thesis is a product development project that was performed at Alfa Laval Tumba AB. In the past Alfa Laval have manufactured gas separators for engines where gas flows were cleaned from oil. A new business area for this kind of technology has shown to be the manufacturing industry where oil mist has to be separated from the vented air. Therefore a new and bigger design is needed to be able to handle the greater gas flows. A product like that would be a strong competitor on the market when the maintenance would be low in comparison to today?s equipment.During the project several concept suggestions were developed using customer interviews and research as input.

Comparison of real-time PCR assays for screening of meticillin-resistant Staphylococcus aureus

Staphylococcus aureus belongs to the normal flora. Many healthy people are colonized by the bacterium mainly in the nose but also on the skin and on other mucous membranes without showing symptoms. After damage to the skin, the bacterium can enter the wound and cause infections. Methicillin-resistant S. aureus (MRSA) is resistant to b-lactam antibiotics such as penicillin and methicillin.

Aerodynamisk optimering av vindkraftverks rotorblad med en genetisk algoritm, BEM-teori, och XFOIL

This study presents a methodology that enables the annual average power of a wind turbine to be increased by automatically optimizing it?s airfoil, twist and chord dis- tribution. As a part of the study the software SiteOpt has been developed. This software connects the open source software XFOIL with the blade element momen- tum theory. XFOIL gives lift and drag coefficients which enable the blade element momentum theory to predict the power of a wind turbine at different wind and ro- tational speeds.

Vad är ?rätt? gjutkvalitet? Hur uppnås det?

Ever since ABB has begun diecasting their Rotors instead of permanent mold casting it,variation in the quality of the cast has arisen. Diecasting is performed in three differentmachines, M1, M2, M3 with 400, 660 respectively 800 tons of die locking pressures.The aim of this thesis is to answer the following questions:What is the ?right? cast quality? How is the right quality achieved?For sizes 160-180 solutions will be proposed that consider eccentricity between thelaminate and the short circuit ring as well as elimination of the thin Al film that appearson the outer periphery of the Rotors.Through considering the statistic material the most often diverging Rotor type has beenidentified and one of the actual Rotors has been sent to a laboratory to be analyzed inorder to establish the current defects. The result of the analysis shows that there areplenty of gas- and oxide-porosity.It has been proved that every time the dies temperature decreased below 120°C thecontent of gas porosity increased. It is due to rapid solidification of metal that flowsthrough the ?cold? laminate.It has confirmed that enhanced porosity in squirrel cage causes high impedance in theRotors.

Vindkraftsetablering i skog

This thesis assignment at C-level is focused on calculation models and prediction methodswhish can be used in the stage we call ?prospecting? of possible windmill locations. Thelocation is southeast of Halmstad at the Farm ?Stjernarpsgods?. The rapport has two mainareas directed towards this task.

Projektering av vindkraft i turbulensintensiva områden : med fallstudie för Wallenstams planerade park vid Skuggetorp

Along with the rapid expansion of wind power in Sweden during the last decades the competition about favorable areas has hardened. This among other reasons has caused the projectors to look into development of wind power in forests. There are several aspects regarding fatigue loads on the constructions that are severe in complex terrain, among which turbulence is one. The levels of turbulence which are accepted in order for the turbines to face a life length exceeding 20 years are regulated by the International Electrotechnical Commission, (IEC). In order to keep the turbulence below these levels there are three major steering tools to use: The ambient turbulence decreases with height and can therefore be regulated by the hub height of the turbines.

Ständiga förbättringar: utvärdering av rutin för
avvikelsehantering och genomförande av förbättringsprojekt
med tillämpning av statistisk processtyrning

Detta examensarbete är utfört vid Indexator AB som bland annat tillverkar lågvarvande vingmotorer för runtomsvängande hantering av gods. Bakgrunden till examensarbetet är att företaget sett en ökande trend i andelen kassationer. Syftet med examensarbetet är att undersöka om rutinen för hantering av avvikelser uppfyller grunderna för ständiga förbättringar och om hantering och uppföljning av avvikelser sker på ett effektivt och systematiskt sätt. Målet är att ge förbättringsförslag som förbättrar rutinen. Examensarbetet syftar också till att identifiera och genomföra ett förbättringsprojekt med tillämpning av statistisk processtyrning.

CARABAS III Konstruktion av antenninstallation på helikopter

This report describes the construction work of a radar antenna for the radar systemCARABAS. CARABAS is a long wave airborne ground radar that has been developed bySAAB Microwave Systems and will now be mounted on a small helicopter, Schweizer 300.The antenna should be able to fold up and down. When the radar is in use the antenna islowered and under transport, start and landing the antenna is folded up. An emergency dropfunction should also be included in the design of CARABAS III.The extent of this report includes construction of the antenna, frame structure attached to thehelicopter, mechanism for folding the antenna up and down and mechanism for emergencydrop function. The mechanical design of the antenna and frame structure is based on modaland stress analysis, vibration measurement of Schweizer 300 and frequency analysis, andcalculations regarding aerodynamic drag and mechanics.The exciting frequencies of the helicopter and accelerations at those frequencies weredetermined by vibration measurement and frequency analysis.

Fuktåterföring i roterande värmeväxlare

För att ha en chans att ändra trenden med ökande utsläpp av växthusgaser är internationella samarbeten nödvändiga. Därför har EU genom miljökvalitetsmålet Begränsad Miljöpåverkan satt krav på högsta tillåtna utsläpp av växthusgaser. Att sänka energianvändningen för upp- värmning är ett steg i att även sänka utsläpp av koldioxid, som är en av växthusgaserna. Sänkning av energianvändning kan göras på flera sätt, bl.a. genom att öka tjockleken på isoleringen eller återvinna värmen i frånluften. Men dessa åtgärder ska inte helt okritiskt göras.

Utredning av solenergi för drivning av sorptiv kylprocess för inomhusluften på Stockholmsarenan

Cooling down the indoor air can be done in several ways. One way is desiccantcooling which will be used at the Stockholm Arena. This method is used in airhandling units that use temperature changes and moisture fluctuations in the air. Oneof the steps is to add heat during the cooling process in order to reduce the relativehumidity of the exhaust air. The air passes thru an adsorptions Rotor which thenabsorbs moisture from the supply air.

Urban vindkraft : Vindkraftsprojekt Järvafältet & vindkraft i Sverige

Wind power is an energy source that is becoming increasingly popular in Sweden and around the world. The establishment of large wind farms supply and contributes to energy production within grid in search of a more sustainable energy production. Wind power is becoming more popular and opens up new areas of implementation. More cities are starting to use small-scale urban wind power, everything from full-scale work for a little less work adapted to the villas. Sweden has high goals regarding the production of green electricity and the work which deals with the conditions Sweden plays in achieving those goals.

Bygglovsbefriad vindkraft till småhuset : -Ur ett tekniskt och ekonomiskt perspektiv

In connection with the property crises in many countries, caused by the financial crises, people are now more aware of the risks involved in poor property-investments. The unusually cold winters along with extreme prices of electricity in Sweden in recent years has also contributed to increased interest in energy-efficient buildings.The process of developing a modern family home in Kiruna, Sweden is presented the first part of this paper. The house has been designed to withstand very high stresses from snow, low energy consumption as well as a high standard of living comfort. Aspects of the house covered here involves everything from construction, heating and ventilation to sanitation. Each of these areas is presented based on their underlying, scientific methods or theories.

Reducering av släpförluster

För att öka köreffektivitet och säkerhet samt minska bromsarnas slitage är de flesta av Scanias lastbilar och bussar utrustade med en hjälpbroms, så kallad retarder. En retarder arbetar generellt sett enligt någon av följande två principer. Dels en elektromagnetisk variant av retarder som bromsar bilens kardanaxel, drivaxlar eller växellåda genom att utnyttja elektromagnetisk induktion, eller som i Scanias fall där man använder sig av en hydrodynamisk tillsatsbroms som bromsar bilens kardanaxel genom att slunga vätska inom ett skovelsystem. Bromsenergin övergår då till värmeenergi som i sin tur kyls bort av bilens ordinarie vattenkylsystem. Bromsmomentet styrs via trycket som råder mellan skovelbladen.

En utvärdering av reduceringstekniker för VOC på Beckers Group

Denna rapport är en studie där tre olika reningstekniker för att reducera utsläppen av VOC, (volatile organic compounds) på färgföretaget Beckers Group, jämförs och utvärderas. De reduceringsmetoder Beckers använder sig av i dagsläget vilka ska jämföras är på anläggningen i Sverige en uppkoncentrering med en zeolitRotor följt av katalytisk förbränning. Anläggningarna i Kina har ett skrubbertorn med diesel följt av en aktiv kolbädd som polersteg. Anläggningarna i USA har en katalytisk förbränningsmetod kallad Oxidizer.Teknikerna jämförs och utvärderas utifrån teknik, miljö och ekonomi i rapporten. Rapporten inleds med att teori gällande färgtillverkning, lösningsmedel och reningsteknikerna redogörs.

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