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3173 Uppsatser om Heating systems - Sida 16 av 212
Automatisk trimning av drivsystemreglering från MATLAB
This master thesis covers the development of an automatic tuning process for the existing speed controller for drive systems. The drive systems are resonant two-mass systems where a motor is used to drive a load connected by a shaft. The developed method relies heavily on system identification and the construction of a complete mechanical model of the process. With this approach, the common problem with poor load speed control that derives from measuring only the motor speed can be addressed and solved for a majority of such processes.The automatic tuning method has along with general test functions been implemented in a complete tool for automatic tuning, testing and performance evaluation and reporting for drive systems..
Webbens klassifikationssystem. En komparativ studie
This thesis deals with subject-based hierarchical search-services on the World Wide Web. The purpose is to investigate how systems of this kind facilitate information retrieval through subject-based information seeking. Its starting point is taken from the study of texts and qualitative analyses of search-services on the World Wide Web. Important aspects and features of the Internet and the World Wide Web are explained as well. Three systems are examined: Mölndals Stadsbiblioteks Länkkatalog, Svesök, and Alta Vista.
Utvärdering av vattenrening och identifiering avförluster m a p energi vid Bravikens pappersmaskin 53
This Master degree project has been performed at the Braviken paper mill on papermachine 53 (PM53) which produces newsprint paper. The current economic situationhas contributed to declining demand for newsprint, which means it is extra important tobe competitive by high energy efficiency. Particularly as energy prices are expected torise when the economic growth returns.One way to increase energy efficiency is by reducing the water use in paper and pulpmills and consequently save energy through reduced heating of water. The thesis's maintask is to evaluate whether a water purification plant (microflotation plant) forpurification of process water in PM 53 is profitable. The microflotation plant enablesreuse of warm process water instead of losing the energy to receiving waters.
Distribuerade fastighetsautomationssystem : - En implementation av kommunikationsprotokollet BACnet
Building Automation Systems in commercial buildings are often designed and installed by different contractors, using equipment and components from different manufacturers. The lack of an accepted communication standard has resulted in a few different standards. Many manufacturers of building automation systems only support one, a few or none of these standards, while developing proprietary system solutions. Regin, who develop such equipment, are planning to adopt an open communication protocol specially designed for building automation - BACnet. As a step in that direction this thesis was announced with the purpose to investigate the possibility to implement BACnet in one of their products and to gain more knowledge of the BACnet protocol.
XML som informationsbärare för EDI
Information handling has been a key issue for different companies for a long time. Electronic Data Interchange (EDI) is used to transfer different business documents from one company to another. This is done in such way that the information itself is separated from how this information is stored and handled in the companies internal systems. As different companies have different systems there is a need for a standardised format for this exchange. There is a big difference between EDI-systems based on what kind of EDI-standard is used.
Vibrationsdämpning av värmepump
Thermia Värme AB is one of the market leading manufactures of heat pumps. In order tomaintain this position, the company wants to improve the vibration characteristics of theirproducts. The aim of this thesis is to develop product design changes that lead to a reductionof vibrations in the heat pump Thermia Diplomat 8.The main cause for vibrations in the system is flow pulsation and mechanical forces inducedby the scroll compressor. Vibration is transmitted through the compressor piping and receivedby the heat exchangers, from where it is further transmitted to the connection points for theradiator and heat source circuits.A number of design changes in order to improve the vibration characteristics have beenevaluated through calculations and practical experiments. The changes have included thecompressor and heat exchanger mountings, the compressor suction and discharge line pipingand also pulsation dampening.The results of the experiments show that the vibration levels in the connections for the heatingand brine circuits can be decreased strikingly through changes in suction and discharge linepiping.
Undersökning av luftkvaliteten vid småskalig biobränsleförbränning i två kommuner med modellsystemet VEDAIR
An Internet application, VEDAIR, for estimation of air quality in regions with small-scale combustion of bio fuel has been developed by Swedish Meteorological and Hydrological Institute with financing from Swedish Energy Agency and Swedish Environmental Protection Agency. The model contains user interface and a coupled model concept where concentrations of atmospheric pollutions are calculated for regional, urban and local contributions. In this report the model is described and a first study of air quality considering PM10 (particles with a diameter less than 10 µm) in two Swedish municipalities, Vänersborg and Gnosjö, is introduced.According to the result, there are areas with poor air quality even in smaller Swedish municipalities, mostly due to high emission from buildings with older wood heating furnace without hydraulic accumulator.In Vänersborg three areas were analysed in VEDAIR for the year 2003: Vargön, Mariedal and the downtown district. In the whole municipality the upper evaluation threshold for PM10, which is defined as 14 µg/m3 for annual average, was exceeded due to background contribution of particles. In all areas, however, the concentrations of PM10 were less than the environmental quality norms.
Svenska hushålls vedarbete : en fallstudie i Umeåregionen
In Sweden there are 354 000 private individuals owning forest. Of these forest owners there are at least two thirds that are self-employed, which means that about 215 000 forest owners conduct some kind of work in their own forest. Those numbers do not refer to firewood production, but every year 7.3 million piled cubic meters of firewood are used for heating Swedish households. This implies that many households are also producing firewood.
The objective of this study was to assess and analyse the small-scale firewood production in the Umeå-region in terms of persons engaged in the work, equipment used, produced volumes and share of forest-owning households involved in these activities. According to results from a questionnaire, the average firewood producing person is a man between 40-60 years old.
Underlag till energieffektiviserande åtgärder i nätstationer
Umeå Energi are working towards a goal, that in the year of 2018, they will be completely climate neutral. As a part of this, one target is to reduce their grid losses by 4 % of the 2012 level, which corresponds to an overall reduction of the grid losses of just over 1.7 GWh. In many residential areas, the distribution grid is designed and rated for electric heating as the heating in the houses. As many of the houses later has been converted to other types of heating, their electricity use has decreased and the total power output from many of the secondary substations has decreased significantly. Because of this, many of these stations today are well oversized, which in turn means that the energy losses in these stations are unnecessarily high.In this degree project, 25 secondary substations have been studied, all located in residential areas in and around central Umeå.
Deriving ECA-rules from timed-automata specifications.
Real-time systems are required to answer to external stimuli within a specified time-period. For this to be possible, the systems behaviour must be predictable. The use of active databases in real-time systems introduces unpredictability in the system, e.g. due to their use of active rules. The behaviour in active databases is usually specified in ECA-rules.
Effektivare elanvändning på avfallskraftvärmeverk : Förslag till handlingsplan för minskad elanvändning på Renovas anläggning i Göteborg
This thesis has identified and studied measures to allow for reduced use of electricity in a waste incineration plant in western Sweden. The energy extracted from the waste at the powerplant is utilized and sold in form of electricity and heat. Technical and environmentally the combined heat and power plant is by today's standards among the leading waste incineration plants in the world. The owners are constantly striving to improve the efficiency of the waste incineration plant. They have seen the opportunities for savings in reducing internal usage of electricity.
Hantering av informationssystem
Lund who has over 90 systems in 12 departments and now wants to streamline the management of these IT systems. Governance of IT systems is something that Lund would treat as it carried a large amount of changes in their practices, where the control is something missed in trying to standardize their systems. What's missing for Lund Municipality is routine to fall back on in order to streamline the management when they get into these complex situations.Given that Lund treat so many systems make it so that the situation quickly becomes very complex due of the organization's structure. The municipality is divided into twelve departments that have their own goals, it is an organization that is organized, which makes creating standards become complicated when all departments have different needs. Our study was based on a framework that deals with complex environments that lack a clear definition.An analysis was conducted where we started from the theory associated with the interviews conducted in which we aimed to understand their decision and understand the processes that affect system development.
Energieffektiva värmesystem : Lösningen till att nå energimålen i byggbranschen?
Sweden has an environmental goal to achieve until the year 2020. To achieve this goal the construction business has to take an initiative to use the modern techniques that are available to lower the energy consumption I buildings. There?s also a debate going on today regarding the energy demands set by the Swedish government through Boverket, some communities throughout Sweden thinks that the demands are to low and have therefore set up own demands regarding energy in buildings.The possibility to construct energy-saving buildings is today very great, with energy-efficient heating-systems and dense climate envelope. The interest to raise energy-efficient buildings have also increased as a consequence that the population have become more aware about their impact on the environment.
Underlag för BREEAM-certifiering : Kristianstad Nya Galleria
The company Olofsfors AB manufactures drive belts for forest machinery, known as ECO-Tracks, and abrasion-resistant steel and cutting edges for graders, excavators and tractors, known as Bruxite and SharqEdges. Manufacturing these products requires the steel to be heated and molded, then submerged in water and hardened. The water used in the hardening of steel is pumped to the process from pits below the floor and then pumped back to the pit after it?s been used. Since the temperature of this water rises after being used to harden the steel the temperature of the pumping pit needs to be adjusted to maintain its setpoint of 21°C.
Leanuppgift för industriprogrammet
The government regulations for energy use in buildings will be tightened in the future. At the same time the interest in environmental classifications and certifications of buildings is increasing. This has meant a new situation for solar energy. The designs of solar Heating systems are often based on experience and/or rules of thumb, rather than calculations and simulations. This thesis examines whether simulation tools, in this case Polysun, are useful in this work.