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919 Uppsatser om Heat storage - Sida 39 av 62

Isolerande och skyddande dubbelväv - Produktutveckling av ett kylande fodral

Denna rapport beskriver en produktutvecklingsprocess som behandlar utvecklandet av ett textilt material som isolerar och skyddar. Det textila materialet ska fungera till ett kylande fodral utan att förstöra dess funktion och behöver därför uppfylla en speciell kravspecifikation. Materialet ska isolera mot kroppsvärme, vara stabilt, skyddande och slitstarkt. Dubbelväv valdes tidigt i arbetet då det är ett enkelt sätt att kunna påverka det textila materialets egenskaper i form av material- och konstruktionsval, i en betydligt större utsträckning än i en enkelsidig väv. För att utveckla ett material med de efterfrågade egenskaperna har tester utförs och den metod som har använts är hypotesprövning.

En jämförande studie av fluiddynamiken för olika fluidiseringsmedium i en kallmodell av en 100 kW-anläggning för kemcyklisk förbränning

To reduce emissions of carbon dioxide (CO2) Carbon Capture and Storage (CCS) technologieshave been developed. Chemical Looping Combustion (CLC) is a CO2 capture technologywith the CCS framework, and at Chalmers University of Technology in Gothenburg,Sweden, a 100 kW chemical looping combustor has been built.This project aimed to investigate to what degree air can replace helium as the uidizinggas for uid dynamical studies in a CLC cold ow model of the above mentioned 100 kWfacility. Experiments were performed using air and helium separately as uidizing gas andpressure data were obtained, which formed the basis for the comparison. The project alsoaimed to investigate uid dynamics in the uidized bed and study when the risk of sluggingoccuring was greatest. The results were presented in the form of figures and tables dividedinto pressure, concentration and standard deviation of the pressure.The results obtained showed that air as uidizing gas did not create the same uid dynamicsas helium over the entire fuel reactor.

Strömkontroll till aktiva magnetlager med noggrann och störningsreducerad strömmätning

There is always a need for more effective ways to store energy in order to reduce the human impact on the environment. One step on the way can be the use of flywheels as kinetic energy storage devices. Low frictional losses are essential for a flywheel to be effective. To minimize these losses active magnetic bearings (AMB) can be used to keep the shaft centered instead of the more conventional ball-bearings. AMBs use actuators and a fast control system that needs correct and noise-free measurement data of the shaft position and the current in the actuators to work properly.This thesis explains the process of constructing power electronics and a current measurement system for active magnetic bearings (AMB).

Automatisk tändning till modern vedpanna

If you have access to wood, a wood burning boiler is a cheap way to heat your home, but it is certainly not the most convenient option. Wood requires many operations and management, which takes time. One way to reduce this workload is to have a modern boiler with automatic ignition. Enertech/CTC has a desire to create an accessory with automatic ignition to a modern wood burning boiler. Today there is no boiler on the market that can ignite firewood automatically without the introduction of paper and sticks.

Energianvändning i badhus : Simulering och jämförelse av gamla och nya system

Every year new premises are built in Sweden, and even if they are made as energy efficient as possible, this will not reduce the energy demands, but the rate of the increase of the energy use will be reduced. One type of facility in Sweden that is a major energy user is public baths, and this makes public baths an interesting facility to study more closely. There are around 500 public baths in Sweden and about 75 % of those can be seen as older baths with large need of renovation, and they all require a high level of energy efficiency measures. To show how the energy demand increase or decrease depending on the changes chosen to be made, the simulation application IDA Indoor Climate and Energy was used. Simulations were made and compared for several cases, with two extreme cases as starting points.

Simulering av valkar i pappersrullar : och analys av de slappa stråk som uppkommer

A baggy paper web has parts that are longer than neighboring parts. One of the assumed reasons for bagginess is thickness variations of the paper. In the roll the thicker streaks then add up to form a ridge. In the ridges the paper is strained and during storage the strain may become permanent. When the paper unreeled it is then baggy.

Magasin för lagring av vatten och växtnäring

Structural rationalizations and regionalization of the agricultural sector in Sweden has lead to unevenness in thedistribution of plant nutrients. Nutrients are lost from crop producing farms as harvest products are sold, whilefarms with animal production often have manure in excess of their needs. In addition to this the retention ofwater and nutrients in naturally occurring wetlands has decreased due to a reduction of wetlands in number andsize in the agricultural landscape. This increases nutrient levels in agricultural run-off and causes eutrophicationas well as nutrient losses from arable soils. One potential solution to both problems would be to store nutrientrichsurface water from agricultural areas and use it for irrigation of agricultural crops.

Morgondagens arkiv : Om arkivhantering i framtiden

The aim of this study has been to create a future scenario of what archiving might look like in the future. The main theory used in the study comes from future studies, but also a theory about the social impact of technology on work were used. The questions that were analysed were about the tasks of the archivist, the appearance of the archival institution, collaboration with other LAM institutions, knowledge requirements for the archivist and the amount of archivist positions. The method used in the study was scenario writing, which derives from future studies. The source material consisted among other things of regulations and laws related to archiving together with some archival manuals.The tasks of the future archivist will probably consist of the same tasks as those of present archivists who work with digital archiving, even though archivists probably forever also will have to work a little with paper records.The future archival institution will probably retain its paper records and keep its digital records on digital storage media.

Energioptimering : Resteffektkylning av mellanlager för använt kärnbränsle (CLAB) Oskarshamn

This thesis is done in cooperation with SWECO Energuide in Växjö. They have been assigned by SKB in Oskarshamn to renew their electrical power supply and the ancillary processing systems in their Central provisional storage of spent nuclear fuel, CLAB. Today in the CLAB facility, the spent fuel is cooled down with water pumps, driven by asynchronous induction motors, where the water is regulated by mechanical valves to the desired flow. After the upgrade, the engines will be powered by AC drives that can control the pumps by changing the rotational speed and thus change the water's cooling effect on the nuclear fuel. In this study, I investigated the interference AC drives causes the feeding network and how to go about averting them.

Brikettillverkning på gårdsnivå :

In my work I have chosen to examine the profitability for small scale production of hemp briquettes. My study also includes a review of which briquette technique that is the most common one among small scale producers. The reason that I have chosen this subject is because of the discussions about climate and energy that we face almost every day. I also think the subject is extra interesting in these days when the grain prizes are at a historic high level. In order for me to achieve a reliable report, a hemp and briquette producer has given me the actual data from his farm. In that way I have been able to make my calculations from a concrete perspective.

Mjölkraskvigors tillväxt på naturbete :

To turn the dairy heifers out on pasture is the most natural way for the cattle to get feed. At the same time it is cheap and if it is right treated a feed of high nutritive value. The problem today is to get dairy heifers to grow enough when they are grazing at natural pasture for the entire summer. Therefore, the opinions differ whether pasture is a resource or a problem. The increasing interest of pasture production is due to the fact that you can receive grants for preserving valuable natural assets and cultural landscape elements in the pasture land. A high grazing pressure is necessary to preserve an open landscape and a great variety of species. In the same time the heifers have to supply their nutritive needs in order to grow and be large enough to show heat and be pregnant in right time to calve with a sufficient body size and at an economically right age. This paper includes a literature review on natural pasture, pasture production, and growth of dairy heifers together with own interviews with dairy farmers about their point of view to the pasture husbandry on the farms, how they plan for pasture, look after natural pasture, treatment areas and take care of the calves and heifers. The results indicate that the time it takes and the demanded work are the biggest factors to how and why the farmers do as they do..

Galactose in dairy products

Milk and milk consumption has been subject of discussion for a long time, and is still a hot topic. Recently, as study was published that observed a correlation between milk intake and increased risk of fractures and mortality. The authors proposed the milk?s content of D-galactose as the possible mechanism, since D-galactose is used indicated ageing in animal models. Therefore, this study aims to develop a method to determine the amount of galactose, glucose and lactose in milk and fermented milk and apply it on to dairy products on the Swedish market.

Smärtlindring hos kalv efter avhorning. En beteendestudie där effekten av meloxikam som postoperativ analgesi utvärderas :

In this study, 29 calves were dehorned by heat cauterisation at the age of 1 to 8 weeks. Before the procedure, the calves were given local anaesthetic but were not sedated. In connection with the dehorning, 14 calves were given the non-steroidal anti-inflammatory drug (NSAID) meloxicam and 15 calves were given placebo. During the following three days behavioural studies were performed to investigate if the different treatments had any effect on the calves´ postoperative behaviour. Head shakes, head rubs, kicks and ear flicks were studied, as earlier studies have shown that an increase in these behavioural patterns suggests postoperative pain.

Exosomes as a potential mechanism of intercellular spread of prion protein

Structural rationalizations and regionalization of the agricultural sector in Sweden has lead to unevenness in thedistribution of plant nutrients. Nutrients are lost from crop producing farms as harvest products are sold, whilefarms with animal production often have manure in excess of their needs. In addition to this the retention ofwater and nutrients in naturally occurring wetlands has decreased due to a reduction of wetlands in number andsize in the agricultural landscape. This increases nutrient levels in agricultural run-off and causes eutrophicationas well as nutrient losses from arable soils. One potential solution to both problems would be to store nutrientrichsurface water from agricultural areas and use it for irrigation of agricultural crops.

Ångsterilisering av morötter. Infekterade med Lactobacillus plantarum.

The purpose of the project was to exam steams ability to sterilize carrots infected withLactobacillus plantarum. The project was a cowork with Brämhults Juice AB. They hadobserved an increase of Lactobacillus in the production of carrot juice during the summer. Tokeep the flavour of fresh fruits, the juice is treated carefully with heat. This means that thejuice only stays fresh for a few days, around two weeks for an unopened package and threedays for an opened package.In an attempt to remove the remaining Lactobacillus of the carrots, steam is tested as an extrastep in the production of juice.

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