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187 Uppsatser om Thermal comforts - Sida 6 av 13
Lagring av kyla i bergrum : Undersökning av ett nedlagt oljebergrum
This thesis considers the use of an oldrock cavern as thermal energy storage.With a large system of differentchillers a model was created to find anappropriate future system. There aremainly two trajectories to take. Eitheran installation of chillers needs to bemade or the rock cavern can be used tomeet the future demand of districtcooling in Solna, Sweden. Additionallythis thesis investigates the possibleuse of different techniques to utilizethe phase change energy of water.Simulation shows that it?s possible toutilize the phase-change energy of afluid; however it?s not economicallyfeasible due to the thermodynamiceffects on the Carnot cycle.
Förstudie för kvalitetssäkringav glidande förband vid Hissmoforsvattenkraftsstation : -Specifikt för aggregat G6 och G7
Jämtkraft AB which is a power production company in Sweden has bought two newhydro power units to their station in Hissmofors. The two new generators are using aconcept with sliding stator feet to handle the thermal expansion.The concept with sliding stator feet on hydro electric generators has not beenworking satisfactory on many hydro power stations in Sweden and has caused a lot ofcosts due to long downtimes.The new station in Hissmofors is very important for Jämtkraft AB, and therefore theywant to know how to make sure that the sliding stator feet are working as theyshould. According to theories and a simplified model of the generator the stator feetdisplacement should be around 1 -1,6 mm.The generators are delivered with a surveillance system that will measure thedisplacement of the sliding stator feet. The signal from the system isn?t accessible forJämtkraft AB but it will alarm when the sliding stator feet are malfunctioning.To secure the function of the sliding feet a logger for the surveillance system or adifferent measurement system must be used; if both systems are used Jämtkraft cansecure the function of the surveillance system..
Miljöcertifiering av ett byggnadsminne
Samtidigt som debatten kring jordens klimatförändring är i full gång har intresset för att miljöcertifiera byggnader vuxit oerhört. För fastighetsägare är det en möjlighet att bevisa för sina hyresgäster och köpare att byggnaden är hållbar. Är en byggnad miljöcertifierad har en oberoende part intygat att den uppfyller en nivå av hållbarhet som bestäms utifrån standardiserade kriterier. Fastighetsägaren kan alltså använda certifikatet i marknadsföringssyfte.Den här studien undersökte om en byggnad som är byggnadsminnesförklarad kan miljöcertifieras med Miljöbyggnad. Målet var att hitta kostnadseffektiva lösningar för att uppfylla de miljöcertifieringskriterier som eventuellt inte uppfylls idag.
Småhusutformning och solenergiutnyttjande
This paper goes through solar energy and what uses it has. It is also a guide in the choice of solar collectors forthe real estate that I have drawn for the thesis work.Solar energy is a renewable source of energy from the Sun's light. Energy can be used to produce both heat andelectricity through solar collectors and solar cells. Some of the benefits of solar energy is that it is completely freeto extract, environmentally friendly and virtually maintenance-free. Disadvantages are that the technology isexpensive, does not cover the entire energy needs and takes a long time until it pays.
Validering av glidande statorfötter på Hissmofors G6 och G7
Jämtkraft AB has recently modernized its hydropower station at Hissmofors by replacing four older worn out units with two new units. The generators uses a concept with sliding stator feet to deal with the thermal movements that occur in the stator during operation when the unit is operating intermittently. At other sites, this method revealed shortcomings in the reliability. This has made Jämtkraft AB feel uncertainty about its function and therefore want to investigate it during an early stage. The generators have a built-in monitoring system for the sliding stator feet and by using data from there the function of the sliding stator feet has been investigated. The study focused on how the different stator feet move relative to each other and how the eccentricity and deviation from roundness changed during operation. The results show that there are several indications that the function of the sliding stator feet is not satisfactory.
Påverkan av skogsbrand på litiska arkeologiska fynd ? experimentell simulering av brand
This is a paper about the effects from smoldering fire on lithic objects from an archaeological view.
The introduction gives the background to this paper, a short orientation to forest wildfires and why the work is limited to: flint, quartz, quartzite and slate. Material and methods describes the stone materials and the setup that was used in the temperature logged tests with three replications for each type of material. The fuel in the burnings was peat on a bottom of sand. Flint showed a more drastic effect from heat compared with the other materials. Slate seems to have greater tendencies to change to darker colour and luster at lower temperatures than the other materials.
Gotland ponies on extensive pastures ? a welfare assessment
Swedish farmers have the possibility to be subsidized by EU rural development programme for grazing animals on pastures to promote the biodiversity of flora and fauna. The environmental remedy sometimes does not allow supplementary feed and at the same time the Swedish Animal Welfare Act and the Swedish Agricultural Board?s regulations for animal welfare and protection states that animals, in this case horses, shall be fed with food of good quality and adapted for the species. The regulations also state that they should have an individual feeding regime that enables them to maintain a normal body condition.
The aim with this master thesis has been to investigate if it is possible to keep Gotland ponies on extensive pastures, during late spring and summer and still maintain animal welfare. The horses were assessed every fourth week using a welfare assessment protocol developed in line with the Welfare Quality® project (submitted, Viksten et al) where physical, behavioural and resourcebased parameters were observed.
Twelve one-year old stallions of the breed Gotland ponies purchased from different breeders were used in the study.
Energiåtervinning från gjuteriprocess till fastighet, undersökning för ökat utnyttjande av spillvärme
This diploma work on D-level is made in cooperation with Varnäsföretagen AB in Eskilstuna. The company performs contract manufactured aluminium goods. This work is a continuation on earlier diploma work in Varnäsföretagen AB. Even if the industry process consumes much energy for melting the aluminium goods, they consume a great amount of oil to warm up the building. The purpose of this work is to examine some places in the building and the process to see how much energy it is possible to recycles to the heating system and reduce the costs for heating.
En jämförelsestudie av koldioxidsläpp för en byggnad med trä- respektive betongstomme ur ett livscykelperspektiv
The goal with this examination thesis is to investigate the difference in carbon dioxide emissions between a building with a wooden versus concrete carcassing from a life cycle perspective. The huge amounts of carbon dioxide released into air from human activities must be reduced to prevent serious consequences. A way to limit this issue is through performing a comparative study where the result shows which of two products with the same function has the lowest emission of carbon dioxide, whereof the product with the lowest carbon dioxide pollution can be chosen.To be able to perform a study like this an object has been chosen and studies about life cycle analyses have been done. The rental square meter, the thermal conductivity value, the energy requirements and the placement of the building has been set equal in both framework types. There were solely dissimilarities of the two buildings taken into account when this comparison study was performed.The result of the study is that a building constructed with a wooden carcassing has the lowest amount of carbon dioxide emissions.
Närklimat vid avvänjning av smågrisar :
SUMMARY
Several studies have shown that weaning pigs are in great need of heat. The reason for this is
mainly because the pigs are given very little feed just after weaning. Some of the pig producers
of today have tried to get along with these problems by building some kind of hut for the
pigs. Some of these pig houses have been included in this study.The study has shown shortcoming
functions for the pig cottage. The expected heat increase has not occurred.
Magnetiska egenskaper hos Öje-Diabasen, Dalecarlia
A study of paleomagnetic remanence and anisotropy of magnetic
susceptibility (AMS) has been performed on the Öje-Diabase
in Dalarna, Sweden, and on basic dikes associated with the
alkaliquartzsyenite/granite Noran-pluton in central Sweden.
Based on isolation of directions of characteristic magnetization
in the basic rocks, a division into three different groups (A,B,C)
has been made. Group Aconsists of dolerites of Jotnian origin,
both dolerites from the Öje-Diabase and dikes associated with
the Noran-pluton are included in this group, making them coeval.
Group B is suspected to show a re-magnetization from the later part
of the Svekonorwegian orogeny. Group C belongs to the
Blekinge-Dalarna-Dolerites (BDD). Thermal demagnetization of
dolerites revealed two different types of demagnetization behaviours,
one where magnetite clearly was the source of the remanence, and an
other with a linear decrease in magnetization intensity. The measurements
of magnetic anisotropy reveals a magnetic fabric with an almost
horizontal foliation and a lineation that indicates a fairly uniform NNW/
S-SE flow direction of the magma..
Förbehandlingstekniker och LCA för rötning av organiskt avfall : Modellkonstruktion och Utvärdering med ORWARE
The goal of this master thesis project was to develop computer models of some plausiblepretreatment techniques and to assess the potential benefits/costs of using pretreatment andanaerobic digestion for waste management of organic waste from a system perspective. Forthis purpose a computer program called ORWARE has been used. ORWARE (organic wasteresearch) is a program for making life cycle assessments of waste management. As the mainpart of the project work the ORWARE system has been provided with three new models ofpretreatment techniques. The additions consist of: One model of pretreatment with ultrasound,one model of thermal hydrolysis and one model of a screw press.
Energieffektivisering av arbetsbodar på byggarbetsplatser
Everyone has to take a greater responsibility in energy issues, both individuals and companies. There have been some major developments in the construction industry but there is still a lot to be done. This diploma work thesis presents different methods of making existing construction shed establishments to use less energy. What is possible to do and how much energy is there to be saved? A shed establishment consisting of 8 shed units were studied in this project and the building simulation tool VIP-Energy was used to simulate different types of material in the sheds. An infrared camera was used to locate thermal bridges. There are several factors that can be improved to make a construction shed establishment to use less energy.
Torkning av flis med restvärme : Metoder för att sänka återledningstemperaturen
The purpose of this study has been to evaluate whether a Low temperature bio-mass dryer could be integrated with the local district heating system in Malå. The aim is to increase the thermal efficiency of the cogeneration plant in Malå, by lowering the temperature of the cooling medium. Another benefit that comes from this is improved combustion efficiency at the power plant, since drying the fuel causes an Increase of the heating value.Simulations has been made in Excel, and with use of linear regression, to find out if it is profitable. Data for this purpose has been supplied by the power company Skellefteåkraft and furthermore SMHI.The result of the Calculations shows that a very efficient bio-mass dryer is needed, if yield of investments should be made possible. An Investment of 4,27 Mkr, in a dryer, could at a such criterium return 60000 kr/year, if the price of the biomass is 190kr/MWh.
Hållbar design för en bättre värld -med hemlösa i fokus
The aim of this project is to examine the needs and problems that exists amongst homeless people and to develop a solution that will help them in their everyday life. Since the homeless are a relatively large vulnerable group i Sweden, their everyday lives could be made easier in many ways.A clear definition of the target group is put together to create a good starting point. What state and help orginazations do to help the homelss and the society?s view of the homeless is also relevant and has been documented. Four personal stories have been put together to desicribe cases of clear problems existing in everyday life.Several interesting problems has been defined from the research and acceptance in the communtiy, desire to be seen and heard and a lack of confidence were the main needs.