Sökresultat:
713 Uppsatser om Calculations - Sida 36 av 48
Värmeöverföring i bergvärmesystem : En numerisk analys av den ringformade koaxiala borrhålsvärmeväxlaren
The borehole heat exchangers of today suffer from poor thermal and hydrodynamic performance. The purpose of this thesis is to improve the performance of ground source heat pump systems and thermal energy storages by increasing the energy efficiency of the borehole heat exchangers. For this reason, the annular coaxial borehole heat exchanger (CBHE) has been analyzed. This type of heat exchanger is interesting in terms of both thermal and hydrodynamic performance. A model has been set up in the program Comsol Multiphysics in order to investigate the heat transfer characteristics along the borehole.
Analys av turbulensmodeller för CFD
This thesis has been a part of Forsmarks Kraftgrupp AB's evaluation of a turbulencemodel used in simulation of turbulent flow called PRNS (Partially Resolved NumericalSimulation). This model has promising properties and may be of use in savingcomputational resources. The purpose of this thesis was to analyze this model andcompare it with industrially applied models such as k-omega SST and LES (Large EddySimulations).PRNS works as a hybrid of the k-omega SST and DNS (Direct Numerical Simulation)where a constant, RCP (Resolution Control Parameter) with a value between 0 and 1are selected. This constant is then used in the Calculations and determines thebehavior of the simulation. When RCP is set to zero the equation are the same as fora DNS simulation and when RCP is set to one the equations for k-omega SST issolved.
Revisorers etiska resonemang : En studie av etiskt resonemang hos revisorer utifrån FARs yrkes-
AbstractIntroduction: It has during the latest years occurred several large business scandals both abroad and in Sweden where auditors have been involved. The need for stabile conditions and well functioning professional codes of ethics for companies, especially auditing firms have been growing during the latest years. FAR has seen it as their task to define the meaning of the Swedish term ?god revisorssed?. This is specified through FAR?s nine professional codes of ethics, which came out in a new edition in 2003.
En jämförelse mellan fyra olika energisystemlösningar : För ett hus byggt efter passivhusstandard i Karlstad
AbstractWork to develop the Eurocodes started in 1975 by the European Commission adopted a program to eliminate trade barriers within the construction area. The goal was to create common European design standards that would replace the member countries' own rules. Eurocodes will replace The National Board of Housing Building and Planning, National Rail, The National Road Administration and other agencies' calculation rules for the buildings structures. The transition to the use of Eurocodes looks like this:Eurocodes set to Swedish standards between 2002 ? 2007They can be used parallel with national standards 2006 - 2009 The total transition is at the end of 2010/2011.Right now is going on a lot of work for replacement of the existing standards to Eurocodes. The transition to the new Calculations` standards, many construction companies and consulting firms facing a big changes and competitions.
Dynamiska egenskaper hos håldäcksbjälklag belastade med gångtrafik
Concrete floors have traditionally had no problems with annoying vibrations. However with the demand for larger spans the floors need to be made more slender with a higher degree of utilization and lower mass. Therefore new floors may have problems with vibration serviceability. This thesis studies the vibration characteristics of hollow core slabs. The analysis was made in the finite element program Ansys. The hollow core slab was subjected to a varying force simulating one person walking across the slab.
Trängselskatt En jämförelse av systemet i Göteborg och Stockholm
SUMMARYInventory of raw materials holds an important role in companies within the manufacturingsector. The inventory works as a buffer that secure the supply of materials to the productionunit. The aim of the inventory is to ensure that the company is able to meet the customers?demands despite fluctuations and variations in the material flow. The size of the warehouseand the layout are physical limitations for the quantity of articles that can be stored.
Effektivisering av råvarulager för lagerhållning av ett bredare artikelsortiment
SUMMARYInventory of raw materials holds an important role in companies within the manufacturingsector. The inventory works as a buffer that secure the supply of materials to the productionunit. The aim of the inventory is to ensure that the company is able to meet the customers?demands despite fluctuations and variations in the material flow. The size of the warehouseand the layout are physical limitations for the quantity of articles that can be stored.
Innovativ utmatningsteknik : Mediumstor bulkförvaringslösning
This master thesis was done for a company called BRUKS which is active in woodprocessing,bio-energy and bulk material handling industry. The idea for the master thesis wasto develop a new reclaiming method for silos where wood chips are being stored. A mediumsegment of between 1000 ? 5000 m3was defined as the segment with the most sales potential.Two different concepts were produced, one for new constructions and one for rebuildingalready existing silos.In the beginning of the master thesis a lot of time was spent on visiting different BRUKSoffices and customers to get an overview of the industry and the product. This informationwas the basis when the idea generating phase began.
CARABAS III Konstruktion av antenninstallation på helikopter
This report describes the construction work of a radar antenna for the radar systemCARABAS. CARABAS is a long wave airborne ground radar that has been developed bySAAB Microwave Systems and will now be mounted on a small helicopter, Schweizer 300.The antenna should be able to fold up and down. When the radar is in use the antenna islowered and under transport, start and landing the antenna is folded up. An emergency dropfunction should also be included in the design of CARABAS III.The extent of this report includes construction of the antenna, frame structure attached to thehelicopter, mechanism for folding the antenna up and down and mechanism for emergencydrop function. The mechanical design of the antenna and frame structure is based on modaland stress analysis, vibration measurement of Schweizer 300 and frequency analysis, andCalculations regarding aerodynamic drag and mechanics.The exciting frequencies of the helicopter and accelerations at those frequencies weredetermined by vibration measurement and frequency analysis.
Åtgärdsförslag och känslighetsanalys vid energieffektivisering ur ett fuktsäkert perspektiv : En fallstudie på timmerhuset Sofiedals herrgård
This thesis investigated the possibilities to resume cultivation of an old manor house built of timber and what this would mean from an energy and moisture perspective. The building in this case study is named Sofiedals mansion and was built in 1858 in Valbo 11 kilometers west of Gävle.The structure of the house was documented and used as a starting-point for carrying out Calculations focused on energy and moisture aspects. With the help of a number of computer programs and a conducted air tightness test, the buildings energy consumption were calculated and compared with the current building regulations.In addition, the building was analyzed considering energy retrofitting and what it meant for moisture problems. The energy retrofitting consisted of additional insulation, decreasing the buildings permeability through air sealing; window and door replacements. When a building is equipped with natural ventilation it is difficult to know its precise performance and how an energy retrofitting affects it.
Ska man tro på aktie-Nostradamus? : en studie om aktierekommendationers värde för privata investerare
Intro: 80 percent of the Swedish population own shares. This makes Sweden the leading country in private investment in securities. It can be difficult for the private investor to know where, when and which security to invest in. The strategies are as ambivalent as the stock markets fluctuations. If the investor prefers to refrain from investing money himself, there are brokers who carry out these types of services.
Livscykelanalys: Pelletspanna från kvänum energi
This study will identify the environmental impact in terms of carbon dioxide for a boiler house on behalf of Kvänum energi. The boiler central consists of a main building, which in turn contains multiple components such as boilers, pipes, etc, the boiler central uses pellets fuel. It also includes a silo and an ash container. The total weight of the boiler is about 63 tons. Each boiler has an output of 600 kW; the central includes three boilers with room for a fourth if necessary.
Gotländsk grönsaksodling : utvecklings- och tillväxtmöjligheter
A diet based on a bigger part of locally produced vegetables can contribute to decreasing
environmental impact and improved health. In Gotland horticulture has increased more than in Sweden in total during the last 15 years. To investigate possibilities for development of Gotland´s horticulture, the cultivation of potato, vegetables, fruits and berries was mapped through a questionnaire among growers. Interviews and a workshop with growers and reseller were conducted to investigate the interest and prerequisites for growing new crops. In total approximately 2340 hectares of potato, vegetables, fruits and berries were grown in Gotland in 2012.
Används ekonomiska planeringshjälpmedel i lantbruksföretag : beslutsunderlag med hjälp av kalkylmetoder
In agricultural educations you learn to use different economic planning tools, as basis for decision. The purpose and goal of this work has been to find out if economic planning tools are used by the farmers in Sweden. We choose to do an investigation through personal interviews, and used an inquiry to get as equivalent answers as possible from the farmers.
This work contains a literature study with relevant facts about the questions that is brought up in the inquiry. This study of literature explains shortly some different calculation methods and bases for decision. It also contains useable information that is important to know before an investment.
The questions that are asked to the farmers have focused on the use of calculation methods and economical planning tools.
Enegiutredning Hotell Princess
This report will show the energy usage of Hotel Princess in Sandviken, Sweden. When the hotel changed owner an examination of the hotels heating, ventilation and sanitary systems were done. The report showed flaws in the ventilation system, and is why the new owner wanted a closer look at the energy use of the hotel. The original building was built in the 1930s and two major extensions have been built, one in the 1950s and the most recent in the 1980s. An assumption made is that the building parts were built to the restrictions during the time. Activities on the hotel include sleep over, conference, night club, massage and swimming in the hotels pool section.