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595 Uppsatser om Stone-heating oven - Sida 2 av 40

Varför svänger stenen? : En studie i curlingens komplexa tribosystem

The tribo system ice-curling stone was investigated in order to understand the mechanisms behind the stones' behavior on the ice sheet. The problem with non-identical stones should also be addressed.The stone curls, that is, its sliding path deviates from a straight line to the right for a clock-wise rotation and to the left for a anti-clock-wise rotation. Several mechanisms to explain this behavior have been proposed over the years but none has been successful.By carrying out experiments at the local curling rink and studying silicon castings of ice- and stone-surfaces with scanning electron microscopy and vertical scanning interferometry, it has been decided that the curl is not due to dry friction, ice-debris or the difference in friction on the left and right side of the stone. The side force comes from the fact that the friction is higher at the back of the stone than at the front.The contact between stone and ice is never completely dry, nor in the hydrodynamic lubrication regime. It is probably a combination of hydrodynamic lubrication and a contribution from mechanical scratching of the ice.

Ytbearbetning av ersättningssten för kulturhistoriska byggnader

The study investigates questions and considerations emerging when stone in historic buildings needs to be replaced. The focus is on the surface treatment of stone in sandstone façades in pre-industrial buildings. That means buildings constructed by traditional methods and craftsmanship without the use of modern technology.The research issue originates from the extensive stonework that is planned for the façades of the Stockholm Palace. The project includes the replacement of large quantities of damaged stone to newly cut stone. This raises the questions about the use of modern and rational methods for surface treatment on the replacement stone.

Olika uppvärmningssystem : en fallstudie i mellansverige

The purpose with this project is to compare different fuels when investing in a central combustion station at a case study farm. I have chosen to write about biofuel from an economical perspective. This because the heating costs are steadily increasing. Also because the farm in this case study has several different heating systems, which are neither profitable nor easy to work with. I have made calculations regarding usage of splinter, wood and grain for the heating system.

Uppvärmning av mjölkgård med ved, flis eller havre :

The background for my thesis is the fact that with rising electricity and oil prices it becomes interesting to calculate on alternative heating systems. I have chosen to calculate upon my parents? farm, which today heats the dwelling house with wood. This is very time-consuming work, time which could be spent on other work. The main objective for this study is to compare three different heating systems to decide how they differ considering effort and cost. The result from the calculations was that grain-heating system demanded the least amount of work, but the total cost was a little higher compared to chips heating. Chips heating required half as much work as today?s wood heating and had a little lower total costs compared with the corn heating. Which system to choose largely depends on how the own work is valued.

Energieffektivisering - Laholms kyrkliga samfällighets kulturhistoriska byggnader

Energy efficiency is today more important than ever, mainly due to the high energy prices and the approaching climate changes. Heating of buildings is an essential area within energy efficiency. Many buildings are old and were built at a time when the energy prices were low and the term ?energy efficiency? was unheard of. By applying today?s broad range of energy saving actions on these old, and thereby often, heating ineffective buildings, this area has a large potential in reducing energy consumption and costs.Churches and chapels are generally old buildings with, in many cases, ineffective heating systems and therefore consume much more energy than needed.

Inventering av processvattenbalans : fastställande av fjärrvärmedistributionens läckage inom Vattenfall Värme Uppsala AB

Heat is distributed to the district heating customers through pipes with water as a heat carrier. The district heating system is complex. To decide what is leakages from the district heating net versus what is the water consumption of the plant, is difficult. Therefore, the purpose of this master thesis is to establish a model where the district heating net?s leakages but also the water consumption of the plant can be followed daily. The project is performed at Vattenfall´s district heating power plant in Uppsala. Information is gathered through discussions, drawings of the plant and guided tours of the plant.

Historia skriven i sten? : Bruket av Kensingtonstenen som historiekultur i svenska och amerikanska utställningsrum

The aim of this master thesis is to analyze how and why Scandinavian-American history has been used in exhibitions in both Scandinavia and the United States after the end of the Great Migration. More specifically, the thesis deals with the Swedish and American exhibitions of the controversial Kensington Rune Stone, discovered in Minnesota in 1898. Despite the fact that its authenticity has been disputed by academic expertise, it has been displayed by many prominent actors. The Rune Stone is one of many purportedly pre-Columbian artifacts found in the United States. Moreover, it is an identity marker, harboring many kinds of identity constructions. The thesis therefore focuses on the meanings that the Rune Stone has been charged with since its discovery, as historical culture and in specific exhibits, on how it has been displayed, and on why it has been exhibited at  national museums in both Sweden and the United States. The principal source materials are five exhibitions of the Kensington Rune Stone.

Kombinerat system för ventilation och rumsuppvärmning : Parameterundersökning i simuleringsmodell för takvärmesystem

A large amount of our time is spent indoors in an artificial climate. To make the experience pleasant there are requirements on the ventilation and the heating system. At the present time the most common form of heating is a radiator system complemented with a ventilation system. A ceiling heating system with combined heating and ventilation can replace the two separated systems. The benefit with a ceiling heating solution is that it saves space since the radiator system is no longer needed.

Projektering av ett småhus samt ekonomisk jämförelse av värmesystem

Design of a house requires knowledge of both technology and economics. Heating and ventilation shall be designed, costs are calculated and estimated and requirements must be fulfilled. Which heating system is to be elected is also a difficult choice, especially with rising energy prices as a factor.The choice of energy system is not always given, because it depends on several factors. Below is a comparison between district heating, geothermal heat pump and electric boiler from an economic standpoint. In a previous report appears district heating and geothermal heat pump as the best options.

Fr?n verktyg till offerg?va. Dep?fyndens roll i V?nersn?s forna sten?lderslandskap, med fokus p? lihultkulturens rituella rum.

This thesis examines five deposits, some of which contain stone axes, at the settlement in V?nersn?s, Sweden. Two of them date to the late Mesolithic era. The aim is to explore the ritual world of the late Mesolithic in V?sterg?tland, Sweden and its relationship to the landscape.

Gravar i Alsike hage : Analys av fyndkontexter och gravkonstruktioner tillhörande gravfältet RAÄ 26 i Alsike socken, Uppland

This essay deals with the results and observations made during excavations in an iron age cemetery in Alsike hage, located in Alsike parish. The excavations took place in 2005 and 2006 and the investigated area comprised two adjacent, but secluded burial-constructions; a square stone setting with a secondary grave, and a stone-built terrace with at least one secondary grave. The artifacts suggests that the TPQ of the stone setting, and the construction date of the rest of the graves, is 900-950 A.D. The aim of this study was to comprehend the course of events in the investigated area, and toanalyse the archaeological finds - in comparison to the well documented an discussed material burial culture in the lake Mälar area ? in order to discuss indicators of gender and social status.Metal artefacts has been preserved as a part of the analysis..

Projektering av småhus med solvärme som huvudkälla

In this report a study has been done regarding different heating systems on which are the mostcomprehensive with solar heating systems. The report has also been focusing if solar power can beused as a primary heating source for supplying more than 50 % of the buildings total heatingproduction. The University of Dalarna constructed a demo-house for this purpose and according tocalculations the total solar usage is more than 50 %. This house has been made for referenceregarding the design of the heating system of property 5:37.Further studies have been made to compare different heating systems that are compatible with asolar system, where the compared systems purpose is to be independent of direct using electricity. Asystem of this design is regarded as sustainable according to environmental as economic issues.

Uppvärmning och miljöpåverkan : -en jämförelse mellan fjärrvärme och bergvärme i villa

Many of todays studies show that district heating is one of the betteralternatives as heating source because of its low environmental load.The energy source is often leftovers from other processes producing energy or waste, like garbage or chips.Electricity in combination with geothermal heating is another heating system that has increased sharply during the last years, and also this system decreases the discharges that have negative affectson the environment compared to several other heating methods.This report aims to, concentrated towards these two different heating systems, estimate the amounts of discharges they indirect cause and how the environment is affected.We have calculated the mean value for discharges of carbon dioxide, nitrogen oxide, sulphur oxide and dust generated from electrical power used in Sweden.Through interviews and research we have gained data for the same substances that district heating based on combustion of garbage and biofuel generates.We have also in cooperation with a housing company chosen a building we see representative for many of the new single-family houses built in Sweden today.Based on its shape and appearance we theoretically created three alternatives of the same house, each of them with climate screens different from each other.Together with the amounts of discharged environmental affecting substances, these houses were the base for our calculations and studies when investigating the different heating sources environmental effect.The results have thereafter been analyzed and discussed from different angles..

Simulering av värmebehov för kombinerad kontors- och laboratoriebyggnad utan traditionellt värmesystem

In this Thesis the possibilities of designing a larger building that is very energy efficient in the sense that it would not need a conventional heating system are discussed. Solar radiation transmitted through the windows, internal heat from occupants, lamps and electric appliances inside the building and heat recovered from the ventilation system then have to be sufficient for the heating of the building. This study is of general interest since the property company, Akademiska Hus, plans to use this study as a first step in determining if this technique could be used in the future and thus be worth further investments. A building without a conventional heating system of the size investigated in this project has not yet been built.The energy needed for the heating of the building was simulated using VIP+.The conclusions from the study are that it is possible to build large buildings without any conventional heating system. This could be achieved in many different ways, for example by lowering the inside temperature or by using better windows and heat recovery system with higher efficiency.

Energieffektivisering i ett verkstadsföretag : En analys av energibesparande åtgärder samt uppvärmnings- och kylsystems driftkostnader och koldioxidutsläpp

The energy use in a workshop company has been examined in this work in order to find areas for energy efficiency improvement. The combined oil and electricity heating in the company were compared with other alternative heating systems including cooling of the premises in following combinations:Ground source heat pump for heating and coolingDistrict heating and absorption coolingDistrict heating and low temperate surface water coolingEnergy use, operation costs and carbon dioxide emissions were calculated for the current heating systems and the three alternatives including cooling. The ground source heat pump for heating and cooling decreases bought energy with 34 MWh annually compared to current heating only. The district heating and low temperate surface water cooling has the largest reduction of operation cost and carbon dioxide. The operation cost decreases with 42 kSEK and the carbon dioxide with 43 metric ton CO2 annually.

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