Future emission legislation puts great emphasis on increasing the efficiency of the engine, thereby reducing fuel consumption. The tribological contact between cylinder liner and piston ring is where an great amount of energy is lost due to friction, and by reducing these losses an reduction in fuel consumption can be achieved.The aim of this thesis was to evaluate the tested piston ring coatings against a plasma sprayed cylinder liner and rank these combinations of materials for friction and wear resistance. The coatings that were tested was Cr + Al2O3, (Al,Cr)N, two types of CrN and WC / C.The experimental tests were performed with a so-called pin-plate, where used oil with addition of an acidic mixture of sulfuric and nitric acid to mimic the acidic condensate formed when exhausts recirculate, were added with a continuous flow. The results were then analyzed by weighing, studies by optical microscopy and scanning electron microscopy (SEM) and profile measurements.The results from each material combination were that the plasma coated cylinder liner wears too aggressively in order to yield a ranking of the piston ring coatings based on the parameters of friction and wear resistance. It is therefore proposed that an alternative coating on the cylinder liner should be developed, lacking the large abrasive wear on piston rings and that can withstand the corrosive environment resulting in engines equipped with EGR.

Swedish energy policy aims to increase the use of energy from renewable sources and this should be done in a safe, environmentally and sustainable manner. According to the Energy Agency the use bio-fuel increased by 73% between 1990 - 2006. Stands with high share of slash are often located on areas with high productivity which often are located on soils with poor bearing capacity. This will increase traffic on susceptible soil leading to increased ground damage. To reduce the risk of ground damage at slash-forwarding, ground protection is needed.

Swedish energy policy aims to increase the use of energy from renewable sources and this should be done in a safe, environmentally and sustainable manner. According to the Energy Agency the use bio-fuel increased by 73% between 1990 - 2006. Stands with high share of slash are often located on areas with high productivity which often are located on soils with poor bearing capacity. This will increase traffic on susceptible soil leading to increased ground damage. To reduce the risk of ground damage at slash-forwarding, ground protection is needed.

The demand for district heating is expected to decrease in the future, due to competition from heat pumps and energy efficiency measures in buildings. Development of existing district heating systems is therefore necessary for district heating companies to maintain market shares. This Master?s thesis describes and investigates the heat and electricity production and profitability of a combined Organic Rankine Cycle (ORC) and heat pump that is integrated with an existing district heating system. The studied district heating system is utilizing heat from waste incineration. In Sweden waste constitute 20 % of the fuel mix used in district heating systems, and this share is expected to increase in the future.

Waste appears to be a low-cost fuel compared to biofuel. This Masters thesis was conducted for Vattenfall Utveckling AB and deals with how waste in the fuel affects the performance of a SCR-catalyst. Different mechanisms of deactivation were surveyed, focusing on the poisoning mechanism. A literature study was carried out, which was used as a reference when analysing the results.Small samples (9x2x2 cm, 64 pieces) cut out from a full-scale unused honeycomb catalyst were exposed up to 1500h in two different combustion plants, Johannes in Gävle (co-combustion) and Högdalen in Stockholm (waste-combustion). The activity was measured mainly at 300°C but also at 250, 350, 375 and 400°C.

The thesis was performed at Forsmarks Kraftgrupp AB in the department ofmechanical engineering, FTCM. Forsmark nuclear power plant has had problems with cracks in some of the controlrods which are placed in the reactor at Forsmark 3. To investigate the cause of this,material samples were taken from five of the damaged control rods. This sampling ofthe rods resulted too short rods to be transported in the shipping container to theinterim storage facility for used nuclear fuel in Oskarshamn. Control rods are crucial components in a nuclear reactor, regulating the reactoreffect by blocking or unblocking fuel rods. Control rods which have been in thereactor are always handled under water in order to protect against the radiation theyemit. The task was to design a control rod adapter that extends the control rod sotransport can be performed from Forsmark. The goal of the work was a complete setof blueprints so the control rod adapter can be manufactured and mounted on theshort control rods and then be transported to the interim storage facility. The work began with mapping of how control rods normally being handled from thereactor to the interim storage facility.

This thesis aims to examine the viability of various techniques for increased electricity generation in CHP plants and the effect of electricity price fluctuations on the profitability.The techniques examined are fuel dryer, pellet production, methane production, combined methane- and pellet production, seasonal heating storages in caverns and pit heat storages and condensing tail. Using Excel and Matlab, the prerequisites for investment costs, revenues and expenses were calculated.What affects the price of electricity is a combination of economic and technological development, energy prices, economic structure, population changes and weather. Different scenarios for the electricity price were therefore examined. In the base case, the electricity price was given by the Nord Pool electricity price statistics of area three in 2011. Thereafter, WiMo was used to design the electricity scenarios for 2030, which was then applied to the data to obtain the viability of various scenarios. The techniques examined were found to give greater profits to the CHP plant by increasing and optimizing the production of electricity.

Phosphorus is the single most potent contributor to eutrophication of freshwater and has also been shown to contribute to the toxic algae blooms in the Baltic sea. The dynamics and paths of losses of phosphorus from arable lands are not fully understood. It is known that phosphorus can be lost directly from plant material to water. In studies where plant material has been subjected to several freeze-thaw cycles, large amounts of phosphorus have been lost. Most studies have been conducted under field conditions, with many factors effecting the measured losses of phosphorus, such as weather and type of soil. This study was performed in a controlled environment without the presence of soil. Instead of soil, small glass beads were mixed with the plant materials in vessels, to make possible homogeneous leaching with water through the mixture of glass beads and plant materials. In this study, clover, ryegrass and dry straw were cut to pieces, approximately 2 cm long.

The jetengines of today are growing in complexity. Reliability for aircraft engines are of extreme importance, mainly due to safety reasons but also economical ones. This master thesis deals with faultdiagnosis in the turbine section of RM12, the engine used in Saab/BAe's Gripen. Three different faults which can occur in the turbine section was studied. These faults are: clogged fuel nozzle, hole in outlet guide vane and sensor fault.

The increasing oil prices during the last years have made it profitable to use cereal grains as a fuel. When compared with wood, cereals contain higher amounts of Cl, S and ash. The Cl and S content makes the gases from cereal combustion more corrosive than gases from wood combustion. The goal of this master thesis was to find out the variation of Cl, S and ash content for oat grain grown under different conditions. Oats was chosen because in Sweden it's considered as the cereal with the best fuel qualities.

Uppsala County has ambitious environmental aims for the planned residential area inÖstra Sala backe. In this thesis different energy sources have been evaluated todetermine which system that would be most favorable given currently availableinformation about the project. Planned energy usage has been divided into tap waterheating, space heating and power. Three base case scenarios were made with districtheating, small scale bio fuel and heat pump. Solar power and solar heating were thensimulated and the production from the two could individually be deducted from theenergy need in the base cases, constituting 9 different scenarios.

The purpose of this study was to find possible explanations to why the studied herd had an increased incidence of abomasal displacements. The incidence of abomasal displacement in the herd was three times higher than the incidence of an average Swedish herd. The cows in this study were fed a total mixed ration. The different parameters studied were: energy content in food, nutritional content in food, body condition scoring, concomitant other diseases, and blood parameters of glucose, fructosamine, cholesterol, insulin, betahydroxybutyrat and free fatty acids. The author?s suggestions to decrease the problems are to decrease the energy content in the TMR to lower the cows? body condition scores in the dry period and changing the content in the TMR to increase the amount of NDF and adding structure in the form of chopped straw.

Volvo Construction Equipment is one of the worlds largest manufacturer of heavymachinery. In Braås, Sweden, they develop and manufacture articulated haulers inseveral sizes. The biggest, the A40, is capable of loading almost 40 metric tonnes.These haulers have a bogie to distribute the forces of the load evenly onto the two axlesand there wheels. The bogie is constructed using a rigid balance beam on each side ofthe frame connecting the axles or an independent solution using hydropneumatics.An analysis has been made in order to establish the forces created during corneringand through the theory, an estimation of the extensive tyre wear and extra fuelconsumption has been made. All due to the effects of the tyres not being inline with thecornering radius.

This thesis work has been performed at the department of diagnosis and dependability at Volvo Car Company, Torslanda. The background of this project is based on interest in ascertaining how different factors possibly can affect a diagnosis method, which has been developed to find leaks in the fuel tank and evaporation system. According to the OBD II requirements leaks with an orifice diameter larger or equal to 0,5 mm, must be detected. The idea of the diagnosis method is to create an over pressure in the system with an air-pump. The current through the pump is measured and correlates to the power consumed by the pump.

The capacity to extract information from vehicles has the potential to be very beneficial. Performing analysis on information about fuel usage, emission values and other driving properties of a vehicle can lead to great economic and environmental benefits.This report contains descriptions of two prominent systems for retrieving information of this nature from a vehicle, On-Board Diagnostics and FMS-Standard, and of an implementation of FMS-Standard.The conclusion drawn after this investigation is that these systems do indeed offer access to the benefits mentioned earlier, although to varying degrees and with differing prioritisation..