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882 Uppsatser om Pre heating of wood chips - Sida 48 av 59
Fuktutredning av massivträkonstruktion : Analys av vägg utan ångspärr
Rapporten ingår i ett FoU- projekt för Högskolan Dalarna, där målet är att ta fram en konstruktion utan ångspärr som ska klara dagens mått på lufttäthet och fuktkrav.Syftet med denna rapport är att utreda hur fukt påverkar en byggnad medmassivträstomme och olika isoleringsmaterial utan ångspärr. Mineralull och träfiberisolering jämförs mot varandra för att se hur dessa påverkarfuktbelastningen i en väggkonstruktion. Testobjektet är lokaliserat i Dalarna, inget fukttillskott har funnits inomhus i byggnaden.För att genomföra detta arbete har tre stycken olika metoder används. Ensimulering, verkliga uppmätta värden och en provtagning. Fuktsimuleringen genomfördes med hjälp av programmet WUFI, uppmätta värden i form av relativ fuktighet och temperatur har samlats in kontinuerligt under två års tid från väggkonstruktionen via mätsensorer.
Jämförelse Mellan Lätt och Tung Stomme på ett Kontorshus
I början av varje nytt projekt stöter man på de olika alternativ av stomme- och bjälklagskonstruktioner som finns att välja mellan, och frågan blir ofta vilken alternativ som är optimal för den aktuella projekteten.Den optimala lösningen för varje projekt existerar inte, på grund av de olika faktorer och förutsättningar som styr projektet, till exempel: ekonomi, typ av byggnad, terrängtyp etc.Frågeställningen i denna rapport är om limträ eller betong är den mest optimala alternativen som stommaterial i det aktuella projektet.Jämförelsearbetet utgående från förutsättningar har gjorts genom att dimensionera delar av ett projekt med både materialen. Fokus har lagts på skillnader i byggnadshöjd, vindstabilitet och grundläggningen. Resultaten tyder på om man ska bygga ett kontorshus eller flervåningshus vore betong mer lämpligare alternativ jämfört med limträ.Skillnaden i byggnadshöjd finns men är förvånansvärt inte så stor mellan de två olika stommaterial. Dock skillnaden varierar avsevärd när det gäller bjälklagshöjd mellan limträ och betong. Detta pga krav på nedböjning och svikt som ställs på limträbjälklag.Båda stommaterial klara vindstabiliteten utan plintar, som är ganska intressant speciellt med tanke på limträets låga vikt.När det gäller grundläggningen, blev skillnaden betydlig större mellan limträ och betong.Dimensionering enligt Eurokoder har gjorts genom egna handberäkningar och även användandet av programvaran Strusoft..
Energisparande åtgärder för uppvärmning i en 70-tals villa : Energy-saving measures for heating in a 70-century detached house
Detta examensarbete på 15 högskolepoäng har som syfte att undersöka några åtgärder för minskade uppvärmningskostnader. Då det byggs mycket nytt idag får man inte glömma bort alla befintliga byggnader. Det första steget mot minskad energianvändning är att minimera uppvärmningsbehovet. I detta arbete har vissa utvalda åtgärder beräknats på en 70-tals villa för att se vad man sparar in. Genom mätningar och information från villans byggnadsbeskrivning beräknas byggnadsdelarnas U-värden.
Where has the fertilizer gone? Closing the nutrient budget for a eucalyptus fertilization experiment in southern China
An increasing demand for wood products in China has resulted in large areas invested in fast-growing tree plantations of eucalyptus. Eucalyptus plantations are often associated with an intensive management including fertilization. By understanding the effects of fertilization and where in the ecosystem nutrients are accumulated a more sustainable forest management could be achieved. In this study, a nutrient budget including all biomass and soil components was created for Eucalyptus urophylla. The examined nutrients were nitrogen, phosphorus and potassium.
Short-term responses of the field layer vegetation in a south Swedish deciduous forest after establishment of wild boars (Sus scrofa)
Inside the south Swedish national park Dalby Söderskog, wild boars (Sus scrofa L.) have been visiting since 2010. The presence of wild boars has earlier been proven to
impact both soil and vegetation characteristics, both positively and negatively. Still, there is a lack of knowledge regarding the rooting effect on the vegetation in
deciduous forest within the native range. In this study, I have compared the field vegetation collected before and after the invasion of wild boars in 74 permanent experimental plots. More specifically, the study aimed to qualify the effect of wild boar rooting on cover ratio, species richness and species composition in a temperate
deciduous forest.
Teknisk undersökning : Rötgaskammare för småskalig biogasproduktion
Biogas mainly consists of methane and carbon dioxide, where methane is theenergy-rich gas, and is naturally created when organic matter breaks down in absenceof oxygen, also known as anaerobic digestion. A biogas plant re-creates the anaerobicconditions inside a digester where the organic substrate is fed into and digests toproduce biogas. The gas is then used to produce energy by combustion and can beseen as a completely renewable fuel.Today, energy from biogas is used primarily by major stakeholders such asmunicipalities and thus the plants become very large with high investment- andconstruction costs. There are currently few small plants in Sweden, even though thepotential for agriculture and medium-sized to smaller farms to become self-sufficientin terms of electricity and heat is great. Farms have a natural stock of digestibleorganic material in form of manure or crops for example, which are constantlyavailable.
Utvärdering av befintliga passivhus : En byggnadsfysikalisk bedömning och mätningar om temperatur, och fukt analys på ytterväggarna
Energy price are on the way up to a high level that will not diminish in the future make us to focus more on the sustainable development for a better solution of residential houses. Passive house or low energy housing are one of the solution to make residential more environment friendly, in same time it´s a financial security using less energy, and saving money. The last 10 years in Germany and all around Europe the concept of passive house been developed, and people aim to know more about these concept that leading the market more attractive for passive houses. A passive house is a well designed building highly insulated and air tight with mechanical ventilated system for the whole building envelope that minimizes the use of energy for heating [1].The housing company Mimer has chosen to invest in low energy consumption in every new housing project. These future plan projects are decided to use less than 75 kwh per square meter annually in purchased energy [2].This thesis is about new constructed passive houses, and focuses on the evaluations of the temperature, and moisture condition for attic, external walls and joist.
BIM Building Information Model : Hinder & Drivkraft
The construction industry is a costly business such in respect of capital for most construction defects which then require rework, tear down and rebuild again. This study is meaningful awareness of tools that can reduce this best through communication and information sharing between the parties. The construction industry is known as temporary projects organizations, where the construction project consists of several actors who have to communicate and share information between them to avoid mistakes later in the build time. These actors are bounded together thus for the duration of the project, then broken when the project has reached its end. The challenge here is for these actors to apply a tool that can help and simplify communications, information sharing, and perhaps the most important aspect is to create a routine for the association and the shattering of these actors. To implement such behavior using a tool such as BIM in the industry whose size perhaps is indescribable may be a very hard task. BIM (Building Information Model) could be seen as the solution to this problem because it acts as a portal where the actors involved must sign in and communicate, share information, and eventually create a behavior, a routine for this association and division of the actors following the end of the project. The technology could help the involved from the beginning of the project, already in the model stage, break down and prevent any construction barriers when the building has been placed in the works.
Effektivisering av ventilationsprojekt : Bravida Filial Uppsala
In recent years the construction industry has been exposed to increased time pressure which has resulted in a higher amount of wastage. Today 35 % of all construction projects in Sweden is "wasted". Time pressure has risen due to increased competition on the market, with more actors entering the construction business, therefore profit margins decreased which has led to a more pressing need for decreasing the amount of wastage.Bravida is Scandinavia's largest supplier of installations and provides specialist services in electrical installations (heating and sanitation), and ventilation. Mahdi Bawaqneh's task was to investigate where, how and why wastage occurs in the company's projects and how to prevent such wastage. The thesis covers the subjects of lean production, communication in projects and planning of projects.
Styrsystem : För en forskningsutrustning
The division of Engineering Materials at Linköping University, department of Management and Engineering, conducted a research project concerning Fatigue life of thermal barrier coatings during 2009. During this project equipment to provoke these fatigue failure by rapidly heating and cooling test subjects in cycles, was ordered.Design and manufacturing of the equipment was handled internally at LIU.The equipment was built using a furnace that is lowered and raised over the table where the test subject is placed. To keep the temperature of the furnace a lid slides in place to close the downward facing opening of the furnace when it is in the raised position. On this door there is nozzle that is used to cooling of the test subject by air.To make sure that the equipment can work independently you need an automation controller that can evaluate if movement can occur without danger of collisions. The control system also needs to monitor that all elements are performed according to plan.This degree project is based on a modular system from OPTO 22 and includes the configuration of a PLC that will be supplied with logic and a user interface.The degree project resulted in a graphic interface in which a user can set desired values for different parameters and get information about current values for them.
Solenergi på Nordvästra Kungsholmen
The energy that the earth receives from the sun hourly has potential to cover a year?s energy demand in the world. Further, this type of energy is environmentally friendly, natural and free of cost. This report covers solar energy in an urban environment and consists of a case study of installations of photovoltaic cells in a part of the city of Stockholm. It is mainly the economic aspects that are covered but there is also a discussion about the practical consequences and the sustainability as a result of integration of solar energy in an urban environment. The aim of the study is to present results from economic calculations for utilization of solar energy in chosen buildings in Kungsholmen in Stockholm.
Avsättningar i pappersmaskiner : Utbildning och förslag till processförbättringar
Deposits can be formed in the paper machine due to sticky materials from wood and recycled paper. These deposits get stuck on process equipment and cause the product quality to deteriorate and the efficiency of the paper machine is reduced. The purpose of this thesis is to increase the understanding about deposits among machine operators, and to suggest methods that can be used to reduce the amount of deposits formed in Bravikens paper machines.To fulfill the purpose of the thesis a pre-study, a literature review and interviews with machine operators and production staff, were carried out. These methods led to the planning and creation of an education about deposits for machine operators.The education about deposits for machine operators consisted of an interactive lecture to introduce the subject of deposits and a subsequent discussion. This approach was chosen to give the machine operators the opportunity to discuss their work situation on the paper machines related to their new knowledge about deposits.
Vakuumisolering ? Ekonomiskt försvarbart för småhus?
The number of people in the world and the urbanization increases. This leads to a bigger need of space for the built environment, space that soon doesn?t exist. A large portion of humanity?s energy disposal is used for heating of buildings.
En studie över effektiviseringsmöjligheter av fjärrvärmeinstallationer i småhus
Syfte: Syftet med examensarbetet är att undersöka möjligheter till effektivisering av fjärrvärmeinstallationer i småhus med hjälp Lean. Detta har gjorts genom att besvara de tre följande frågeställningarna:Hur ser en fjärrvärmeinstallation i småhus ut i dagsläget?Vilka slöserier går att identifiera i processen för fjärrvärmeinstallation i småhus?Hur kan slöserier i processen för fjärrvärmeinstallation i småhus minskas?Metod: För att uppfylla examensarbetets syfte har en fallstudie genomförts på Jönköping Energi som är en leverantör av fjärrvärme. Där har intervjuer och dokumentationsstudier använts som datainsamlingsmetoder. Litteraturstudier har gjorts för att samla in information kring teorier som sedan använts för att utvärdera och analysera empirin.Resultat: Genom studien har slöserier identifierats i processen för fjärrvärmeinstallation i småhus.
Investeringsbeslut för energieffektivisering i monarken
The purpose of this essay is to describe how Boverkets Byggregler has affected the cost ofnewly built houses from 2003 to 2012, to Boverkets Vision 2025. The purpose is also to findagent-principal relations in the construction sector.When investing in an energy efficient house the operating costs are reduced compared to aconventional house. But due to the lower operating costs, the investment cost rises. In thisstudy, we find out if it is economically viable to invest in an energy efficient house comparedto a conventional house from the customer's perspective.The study's approach has been qualitatively where we in collaboration with Derome Hus hadaccess to three conventional reference houses and a passive house and data that was necessaryto conduct viability assessments on houses. We conducted five interviews with people fromDeromekoncernen and Varbergs kommun.The calculation methods we have used in this study are present value method, annuity methodand a sensitivity analysis.