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499 Uppsatser om Fluid simulation - Sida 17 av 34

Icke-linjära modelleringsteknikerav förspänd betongkonstruktion : Reaktorinneslutningen på Forsmark 3

A new material model, for the FE-program ADINA, has been verified against twoexperiments. One unreinforced concrete beam and one reinforced concrete beam.The model, DF-concrete, has the possibility to estimate true concrete. However theresults indicate that in order to be sure that the estimations are true, there ought tobe data from the true concrete to verify against.Two FE-models have simulated the behavior of a ring-shaped part of the nuclearcontainment vessel. The results from the first, frictionless, model agree with similarsimulations and hand calculations for high pressures in the containment vessel. Thesimulations of the nuclear containment vessel show cracking in the concrete after10-11 bars of over pressurization.

Simuleringsverktyg som hjälpmedel vid optimering av signalavstånd inom järnväg : Simulation tool as a help for optimization of signal distances on a railway track

The project Design analysis and proposals of plastic screw caps in Australia was performed at Högskolan Dalarna incooperation with University of Western Sydney, Australia. The Swedish company Tetra Pak, in Lund, were assigner forthe project that was performed 2006-2007. The commission was to do a survey about the packages for non-carbonateddrinks in Australia. The bottles had to be plastic, able to open in one step and with focus on the caps.The project has result in design analysis and a new proposal of a plastic screw cap for the Australian market. Sixbottles were choosen and they were all testet on 20 consumers each with a Likert-scale test.

Optimering av antenndesign utifrån experimentella data

During the work at Gateway Security AB in Motala I began examining available antenna models to get a wider perspective, this have given knowledge of their structure, and an understanding of their function. All my necessary fact is based on my observations and notes of these measurings. New antenna models, and available models were examined where measurements at different heights and different distances on the antenna were performed with the help of an oscilloscope and a measure probe, peak ? to - peak was brought on the signal. The measurements are presented in a line diagram.

EAS-tagg med fuktsensor : Design och utvärdering av EAS-alarmteknologi för fuktdetektering

Electronic article surveillance (EAS) is widely used in shops and libraries together with an RF-tag attached to the goods or books in order to prevent shoplifting. By implementing the addition of a moisture sensor to the RF-tag, other functions become possible, including the ability to use as an alarm with regards to frozen goods, which have been shipped but which have melted and have, subsequently, refrozen. In- relation to care for the elderly, one time-consuming step involves checking whether there is the necessity for a change of diaper and this can, instead, be based on an RF-tag with an EAS-system alarm. A preliminary investigation was made using the moisture sensors, which involved how the resistance changes when liquid and/or heat is applied. A simulation of the LCCR circuit (RF-tag with the sensor) was conducted in order to determine how the resonance frequency changes for different resistances levels.

Analys av nivåproblematik i dränagetank på Ringhals 1

The focus of this project has been on the drainage tank of the reheater on Ringhals 1. This tank has on two previous occasions received such a high water level that the system automatically emergency stopped. For this reason, events and various readings from these two occasions has been specifically studied and analyzed. In order to prove theories about what causes these problems a model of the system was created in the program Dymola. Using simulation results from the model, we have been able to demonstrate how the system's measured values should look likeunder normal conditions with respect to flows, pressures, temperatures, valve positions and water level in the drainage tank.

Politecast : ett nytt kommunikationsprimitiv för trådlösa sensornätverk

Wireless sensor networks have the potential for becoming a huge market. Ericsson predicts 50 billion devices interconnected to the Internet by the year 2020. Before that, the devices must be made to be able to withstand years of usage without having to change power source as that would be too costly. These devices are typically small, inexpensive and severally resource constrained. Communication is mainly wireless, and the wireless transceiver on the node is typically the most power hungry component.

Mikroproduktion av solel i flerfamiljshus : Lönsamhetsanalys genom simulering av solcellsanläggningar och explorativ kundundersökning

This thesis is commissioned by the Swedish electricity trading company GodEl with the purpose of evaluate solar electricity in multi-family buildings in the Stockholm region. The prices of solar panels have dropped recently due to the advances in technology, but the installation rate in Sweden remains low. It is therefore interesting to study the  profitability of solar electricity today, and if it is profitable enough to install based on profitability alone and not simply due to environmental considerations. Therefore this thesis first studies the profitability of solar panels based on a simulation of electricity production and consumption for multi-family buildings this region. The study concludes that solar electricity can be profitable in the Stockholm region under certain conditions; all of which have to be favourable for profitable solar electricity.The thesis also studies the opinion of the company's costumers concerning solar electricity.

Utformining av vindavledare för flakkåpa

På grund av nya EU-restriktioner måste biltillverkare sänka sina koldioxidutsläpp för att kunna konkurrera på marknaden. Denna rapport behandlar examensarbetet med att utveckla en vindavledare för Autokaross i Floby AB?s flakkåpa monterad på en Volkswagen Transporter. Syftet är att, på grund av framtida EU restriktioner på max 175 CO2/km för lätta transportfordon, sänka bränslekostnaderna och koldioxidutsläppet genom att minska luftmotståndet. En litteraturstudie kring hur aerodynamik fungerar gjordes och dagens marknad undersöktes för att se vilka lösningar som finns idag. Genom att ta del av en kundundersökning som Autokaross i Floby AB gjort kunde kundkrav identifieras vilka utgjorde grunden för kravspecifikationen.

Utvärdering av simulationsträning - finns det evidens för lärande? : En litteraturstudie

På uppdrag av Kliniskt Tränings- och Simulerinscentrum (KTC) kom författarna till denna studie i kontakt med ämnet simulationsträning. Simulationsträning introducerades under 50-talet i den medicinska världen. Sedan dess har det gjorts många framsteg och förbättringar på området, i takt med att kraven ökar på sjuksköterskans arbetsuppgifter. Syftet med den här studien var att studera effekter av simulationsträning. Studien baseras på tio vetenskapliga artiklar vilka behandlar simulationsträning och dess effekter.

Simulator för el- och värmeproduktion : påverkan på ekonomi och miljö

In this project a simulator has been developed (in C++) with the purpose of illustrating how changes in environmental regulations, tax levels and other policy measures affect the composition of an energy system. The aim of the project was to investigate how energy companies? investment strategies are affected when changes in economic and environmental conditions occur. A standard scenario has been created based on current Swedish conditions, but the user can create new scenarios and set parameters freely. The user is tasked with building power plants to supply the city/region with district heating and electricity during a pre-set number of years. When the simulation is finished the result is graded in the following categories: economy, environment and quality. To evaluate the simulator three scenarios were created (?early 20th century?, ?reduced environmental control? and ?future?) in addition to the standard scenario and these were compared with each other by examining how a select group of power plants perform under the given conditions.

Uppskattning av Ytkurvatur och CFD-simuleringar i Mänskliga Bukaortor

By applying a segmentation procedure to two different sets of computed tomography scans, two geometrical models of the abdominal aorta, containing one inlet and two outlets have been constructed. One of these depicts a healthy blood vessel while the other displays one afflicted with a Abdominal Aortic Aneurysm. After inputting these geometries into the computational dynamics software FLUENT, six simulations of laminar, stationary flow of a fluid that was assumed to be Newtonian were performed. The mass flow rate across the model outlet boundaries was varied for the different simulations to produce a basis for a parameter analysis study. The segmentation data was also used as input data to a surface description procedure which produced not only the surface itself, but also the first and second directional derivatives in every one of its defining spatial data points.

Studie av integration mellan rategyron och magnetkompass

This master thesis is a study on how a rategyro triad, an accelerometer triad, and a magnetometer triad can be integrated into a navigation system, estimating a vehicle?s attitude, i.e. its roll, tipp, and heading angles. When only a rategyro triad is used to estimate a vehicle?s attitude, a drift in the attitude occurs due to sensor errors.

Ledinflammationer på häst och intraartikulär behandling med hyaluronsyra : en pilotstudie på hyaluronsyra X

Traumatic arthritis is a common cause of lameness in horses. One of different treatment alternatives of arthritis, is intra-articular injection with hyaluronan. As knowledge about pathophysiology of arthritis and function of hyaluronan is increasing, understanding grows about the mechanism of hyaluronan action in joints. Hyaluronan has, in addition to effects on viscosity, anti-inflammatory and analgesic effects. Extensive research and scientific studies have been made on exogenous hyaluronan.

Tillverkning av mikronålar för medicinsk tillämpning

Transdermal drug delivery, besides painfulinjections with syringes, has long been associatedwith small size particle pharmaceuticals, which candiffuse through the skin. This method of drugadministration has only been applicable on a smallnumber of drugs, where active molecules are smalland delivery time should or can be long.Other drug delivery options are oral administrationand injection with hypodermic needles (ordinaryhospital syringes). In oral administration thestomach and liver tend to dissolve the drug and theeffect becomes more difficult to anticipate, anddrug delivery rates difficult to control. Hypodermicneedles are used as a mean of drug injectiondirectly into the bloodstream. This method ispainful and risks infection due to tissue damageand skin penetration.One way to get a painless non-damaging techniquewith high delivery rate that still can delivery largemolecules is to manufacture an array of microscopichollow needles and equip them with a pumping unitthat delivers the correct amount of drugs.This thesis shows the technique and possibility ofmanufacture micromachined needles using low costtechniques of Ion Track Technology (radiation ofheavy ions creates porous materials), electrolessdeposition (non-current activated wet chemistrymethod of depositing metal) and electroplating.

Läcksökning med penetrant ? kvalitetssäkring av

Vacuum box leak testing is, because of geometrical problems, not always possible andtherefore an alternate test method with dye penetrant is used. DEKRA Industrial has identifieda need for quality assurance of the method and development of a written procedure withguidelines that lead to more uniform ways of testing.A literature study was done to get a general overview of nondestructive testing (NDT) and tosee how the method is used in different applications. European and American standards werestudied. Analytical and numerical solutions, involving flow simulation, were deemed to berather difficult and beyond the scoop of this project. Thus the problems had to be solved byusing experimental methods.

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