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705 Uppsatser om Mechanical ventilation - Sida 16 av 47
Konstruktion av transportvagn för mat
This thesis is the result of the class Examensarbete, 15 credits of the mechanical engineering program at Halmstad University. The class represents the final part of the program with the aim to attain a Bachelor of Science. It´s a project made during the spring 2014 in collaboration with Alutrade AB and ScanBox Thermo Products AB.The assignment is to develop a new transportation trolley for ScanBox. The aim is to complement their range with a product that opens up to new markets. That set new demands for materials and also manufacturing- and assembly methods.
Utvärdering av en Magnetic Harmonic Traction Drive
In this report a new gear concept is evaluated using the magnetic finite element method (FEM)software MagNet and Ansys as well as the mechanical FEM software Abaqus. The gear conceptis evaluated in terms of maximum torque capability, torsional stiffness, gear ratio and efficiency.ABB Corporate Research has proposed a new gear concept which should be less expensive thangearboxes used today. The new concept is called aMagnetic Harmonic Traction Drive and usesthe principles of a harmonic drive gear to achieve a high reduction ratio. The gear conceptreplaces the wave generator used in traditional harmonic drives with magnets and uses tractioninstead of gear teeth to transfer the torque. The main components in the gearbox are the magnets,the flexspline, the magnetic portion and the circular spline.
Omkonstruktion av en rollators bromssystem
This diploma work project is a product development project which purpose is to redesign a braking system for a walking frame. The system that was developed diverges the force from the user to braking power, and includes a service brake as well as a parking brake. The most important components of the system are a grip handle on where the user holds on to and a braking handle on which the user operates the brake from. The system also includes a power transmission component, braking package and other mechanical components. All of the components wasn?t developed in this project, several off them has been reused from the existing system.This product has been developed to meet the requirements and standards presented from the principal, Ahlberg Leber.
Termomekanisk utmattning av Sanicro 25 : Materialmodellering med finita elementmetoden
The report aims to describe the austenitic stainless steel Sanicro 25 from a thermomechanical point of view. The thermal and mechanical properties of the material make it suitable for use in coal ? and thermal power plants. By the use of Sanicro 25 it would be possible to bring the efficiency of these plants up while bringing the carbon emissions down.A material model is created from material testing and validated through simulation in the finite element software Abaqus. The model that has been derived describes the material behavior during loading and stress relaxation for the first cycle in a thermomechanical fatigue test well.
Energikartläggning av förskolor i Halmstad Kommun
Till år 2020 har EU satt upp mål om att sänka energianvändningen med 20 %. År 2013 står fastigheter för 40 % av Sveriges totala energianvändning och är på så vis en starkt bidragande orsak till den höga energianvändningen. Som ett led i detta arbete måste energianvändningen i fastigheter minska.Halmstad Kommun har ett stort fastighetsbestånd, där det äger och förvaltar många förskolor. De förskolor som utvärderas i rapporten är Trollbergets förskola i Söndrums Kyrkby och Askens förskola i Oskarström. De här förskolorna har enligt fastighetsägarna (Halmstad Kommun) en betydligt högre energianvändning än vad som var projekterat.För att undersöka energianvändningen i förskolorna Asken och Trollberget i Halmstad Kommun har det gjorts beräkningar, besiktningar samt enkätundersökningar med personalen. Energiberäkningarna visar att både Asken och Trollberget förbrukar mer energi än vad som är rekommenderat av BBR.
Metoder för lastprioritering i fjärrvärmecentraler
A problem in the field of district heating is the oil burners needed to provide power when a peak load occurs. One possible way of reducing the needed amount of oil is to reduce the power demand for space heating in the district-heating substations when the need for district heating water exceeds a certain limit. This can be done by use of a locally working controller function.In this Thesis the options concerning load priority are evaluated. To evaluate the potential for using controller functions concerning peak load priority an experiment was brought out in a chosen district-heating substation. The impact on the indoor thermal comfort during a heat reduction was also taken into account.
Feedforwardreglering av ventilation på Kiruna flygplats
Denna rapport utreder huruvida feedforwardreglering av ventilationssystemet på Kiruna flygplats leder till lägre energianvändning. Rapporten jämför ett feedforwardreglerat system simulerat i Simulink med ett feedbacksystem som motsvarar det existerande systemet på Kiruna flygplats. Jämförelsen görs på fläktens energianvändning och rapporten använder sedan energianvändning för värme och kyla för att avgöra huruvida systemet är ekonomiskt gångbart. Systemet är tänkt att kunna användas i alla miljöer med kända störningar i avseende till tid och storlek som till exempel flygplatser, biosalonger, teatrar och så vidare.Rapporten ger en kort teoretisk bakgrund till hur ventilationskrav, reglerteknik, feedforwardreglering och feedbackreglering fungerar för att sedan gå vidare till att redogöra för de förutsättningar som gäller för Kiruna flygplats med avseende på klimatskalets täthet, rummens volymer och utformning och drifttiden för ventilationssystemet. Med hjälp av simuleringar i Simulink görs en jämförelse av energianvändning då de båda systemen är optimerade utan att för den sakens skull kompromissa med kvalitén på inomhusmiljön.
Design av motorstyrd lyfthjälp till toalettstol
The objective with this project was to design a new lifting aid connected to toilet chair.A questionnaire distributed at three homes for aged people indicated that there was an interest in a mechatronic lifting device.Since existing products have limited tilting functionality, the new design was chosen to introduce lifting by motorised tilting of the sitting platform. The mechanical construction was analyzed based on a maximum load caused by a person with weight 160 kg. Two linear actuators were used to control the tilting/lifting of the sit ?place, making standing-up easer.Finally, 28 persons tested the new lifting device and gave their impressions. Many appreciated the safe, stable lifting speed.
När ska dieselelektrisk framdrift av fartyg väljas?
Diesel electric propulsion is in many ways a good alternative to conventional shaft propulsion, both economically and environmentally. There are also many other good side effects which need to be considered, i.e. better manoeuvrability, more efficient use of space and less noise on board. However, there are applications where diesel electric propulsion is not profitable. Large ocean going ships? profitability is much depending on fuel costs and the diesel electric alternative cannot compete on long journeys with large low speed engines.This thesis will treat the aspects of choosing between a diesel electric system and a classic mechanical propulsion system.
Förbättring av Camcoil : Integrering av stöd samt bandnyp
AbstractThe assignment were assigned by Camatec Industriteknik AB. Camatec is a Karlstadlocated consulting company, they make everything from pilot studies to complete projects in mechanical design and calculation. They even have their own patented product, Camcoil. It is a winder for steel strips and is used for example with hardening of the steel strip. The assignment has been to solve the problems encountered by some customers within this product.
Broms- och styrsystem för möbeljalusier
This report is the result of a master thesis at the Department of Mechanical Engineering, Division of Industrial and Economical Development, at Linköping University of Technology. The project was carried out on behalf of Fanerami AB, Mjölby and includes 20 weeks of full time schedule work.Cabinets with vertical mounted roller shutters all share the same problem, namely weight balancing. A roller shutter has an equilibrium area where the sum of the different forces acting on the shutter equals zero. As the shutter leaves that area it will pick up speed as it falls towards the bottom. When the shutter hits the bottom of the cabinet there is a potential risk of getting fingers caught and in this project a solution to prevent this from happening was to be presented.In this project, three concepts have been generated with the following different purposes:?In concept 1 the risk of getting any fingers caught when the shutter closes was to be eliminated in an efficient and inexpensive way.?In concept 2 the roller shutter had to be balanced at all time providing the possibility to keep the cabinet open in any position.?The last and most challenging task was to create a remote controlled TV cabinet.
Verifiering av beräknad energiprestanda för flerbostadshus byggda år 2007-2009
The building industry consumes approximately 40 % of the total energy consumption in Sweden, where the using stage is dominating with 80 %. There is a lot of work in progress to reduce energy use in the building industry, and the demands from authorities regarding energy use increases. As a part of this work Building and planning department of Sweden has established a requirement that has been applied since 2006, and restricts a maximum energy use for buildings.The requirement includes that an energy simulation must be done in advance to demonstrate that it is possible to meet the demands.Reality is however more complex than an energy simulation program, that frequently underestimates the energy use of buildings. The purpose of this thesisis to study and analyse deviations between estimated and actual energy use in modern apartment buildings. The study includes four apartment buildings in Stockholm, Gothenburg and Jönköping that were built in 2007-2009.
Underhåll och övervakning av distributionstransformatorer
Följande projekt går i korthet ut på att avgöra om användning av kylsystemet i en transformatorstation är relevant, om det minimerar temperaturhöjningen orsakad av effektförlusterna som transformatorn avger. Arbetet ska resultera i förslag på val av transformatorer samt beskriva dess egenskaper. Vidare vill vi finna lösningar kring problemet med överhettning i transformatorstationerna och att de generella kraven såsom låg ljudnivå och tillräcklig ventilation (för att ta bort den värmeförlust som de inre komponenterna avger) skall uppfyllas. För att kunna ge olika förslag på val av transformator i transformatorstationerna har vi på Holtab AB utfört olika beräkningar som visar skillnad för pris, kvalitet, livslängd och egenskaper (effektförluster, energiförluster)..
Quadrotor UAV : Konstruktion och användbarhetsstudie av en UAV i sensornätverk
Quadrotor UAVs are self-stabilizing, autonomous flying machines that has recently become more popular than ever. Unmanned Aerial Vehicles have their roots in the military, where they were developed for use in reconnaissance and combat. During the last few years, advances in the fields of electronic sensors, electric motors and microcontrollers have enabled smaller designs and autonomic flight control even for private use. The quadrotor, which is the particular kind of UAV we are looking closer at in this paper, has 4 rotors in an X-like formation. This configuration has many advantages such as good lift capacity, non-complex mechanical structure and serviceability.In this project we aquired a current overview of the domain and determine whether it is possible to construct a quadrotor UAV designed for use in a WISENET sensor network on a low budget and short time schedule.Based on existing community project AeroQuad, a quadrotor is constructed with a budget of about 500 euro.
Utveckling i Java av ett pedagogiskt spel i kvantfysik
The game QuantoJump is developed in the programming language Java to be an educational game in quantum physics. By illustrating quantum mechanical laws of electron transitions with shapes and colours, QuantoJump hopes to spark interest and create a more intuitive understanding of quantum physics. The result is a game where the player plays as an electron in the outermost shell of an atom, with the goal of getting to the innermost shell. This while not making forbidden jumps by following the laws of electron transitions dictated by quantum physics. The programming of the game was done in the integrated develpoment environment Eclipse.