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983 Uppsatser om Heat transfer - Sida 6 av 66

Interspecies embryo transfer in South American camelids : a field study

The aim of this study was to investigate the possibility of performing inter-species embryo transfer under actual field conditions in the natural habitat of South American camelids. In this study embryos from llamas were transferred to alpaca recipients. In a parallel study alpaca embryos were transferred to llama recipients. All animals used were free of uterine and ovarian abnormalities detectable by rectal palpation and /or ultrasound examination. Embryos were harvested twice after single ovulation in 10 mated female llamas and non-surgically transferred to synchronized alpaca recipients.

Termisk hantering av litium-jon- batterier i elektriska drivsystem

The automotive market is currently undergoing a historical change where stricter emission legislations and ever increasing fuel costs have intensified the search for effective alternatives to the conventional internal combustion engine, which has resulted in a substantial trend towards electrification of powertrains. Storage of electrical energy is the fundamental component in this technology where the lithium-ion batteries are currently considered as the most appropriate solution. Lithium-ion batteries, however, as other types of batteries, can only be used efficiently and durably within a specific temperature range.This Master thesis has been carried out in collaboration with Electroengine in Sweden AB, situated in Uppsala, which has an ongoing project regarding development of a modular battery system for electric powertrains. The project is at a stage where an initial prototype has been developed which provides the foundation for this thesis. The study has addressed the battery system performance from a thermal perspective, in order to validate the ability of the system to create a thermally serviceable environment for the lithium-ion battery cells.

Miljöbetong

The study aims to reduce energy consumption in apartment buildings where individual metering and charging of heat is applied. The aim is to develop planning and design for individual metering and charging in apartment buildings.The study is based on literature review, interviews and case study that include analysis of existing documents. Interviews were carried out with the property developer and the involved consultants who planned the apartment building Yasuragi. To investigate the differences the condominium association has noted in heat consumption between flats, the debit values of the heat were used to discern which houses that were furthest from the average consumption. On these flats there were temperature measurements and thermal photo shoots made for discriminating behavior and possible construction techniques which could be the explanation for the heat spread.Boverket shows that the consumption of heat can be reduced by 10-20% after insertion of individual metering and charging in an apartment block.

Ljudreducering av värmepump

This degree project handles acoustic measurements of the heat pump EcoAir 107, made by Enertech CTC AB. The sound from the three sound sources of the heat pump, fan, compressor and four way valve, have been measured to find out how they affect the total sound level of the product.Measures to attenuate the sound level have been developed and tested. By comparing these with the sound of the heat pump, in its original state, we have found out the measures which have best effects.The best attenuating measures came to be: taped openings and holes around the compressor space, isolating the top and the bottom of the whole construction, support of the fan bottom part and shielding of the sound source with a screen at a distance of 110 mmThese measures have been tested together and an average attenuation of the total sound level with 3,9 dB have been accomplished. In the front of the fan where the continuous sound is the strongest, the attenuation was 4,7 dB.This project is meant to be used as a guide by Enertech CTC AB:s during their future developing process..

Övergång av verksamhet : En avtalsrättslig tolkning av vad det arbetsrättsligt innebär att enligt 6 b § LAS ta ställning till fortsatt anställning

The swedish law of contract is fundamental within several civil law areas, among others labour law. The labour law contains more explicit legislation specificly adapted to the relation between employers and employees. Sometimes the labour law needs to rely on more general regulations, such as the law of contract. When the situation contains a specific contract relation dilemma it is logical to use the law of contract, when for example the law of employee protection does not reach an acceptabel solution.Transfer of undertaking is a situation were the employee protection is disregarded. The Euro directive 2001/23/EG prescribes, by its implemented rules in the law of employee protection, that rights and duties, such as employement agreements, passes on to the earner of the business.

Morgondagens effektiva fjärrvärme : En beskrivande litteraturstudie

This report is made as a literature review, focusing on the work done to increase understanding of efficiency in the categories of substations and secondary heating systems, with respect to the deviation from the theoretically possible cooling off in the distribution network as well as the economic benefit that appear. The main purpose of a considerable part of the literature used in this report addresses the issue of identifying individual causes of reduced cooling in district heating systems. These literature resources have been compiled and summarized as part of the report.The technology of district heating is associated with benefits such as better use of the energy in a fuel. This is the case of cogeneration plants where serial generation of electricity and thermal energy increases efficiency compared with the parallel generation where heat is generated locally and electricity is generated centrally. Serial generation thus allows for lower primary energy demand.

Sponsor or Die - En studie om imageöverföring vid mindre events

Studies conducted on event marketing have mainly focused on larger events. Managerial implications, marketing techniques, and theories in the field have hence dominantly addressed events of larger nature. Event marketing however is a growing phenomenon in the marketing mix. Brands are using event marketing to a greater extent. Brands are increasingly using small events as a marketing tool in order to create brand awareness and brand image; this goes for both small brands and large brands.

GNSS-Styrning : Information för platschefer

An investigation of the heat impact of laser cutting on the material properties when producing tensile and impact test specimens of different steel types of varying thickness has been performed. The purpose of the thesis project was to provide recommendations regarding how much material that needs to be milled from the laser cut edge before tensile and impact tests. The study has been performed partly by investigating the test specimens by heat camera when the specimens were cut in the laser cutting line and partly by performing hardness tests, investigation by microscopy, and tolerance and roughness measurements and tensile tests of the laser cut material and material produced in the traditional multi operation machine. The results show that the heat affected zone in the thicker materials is greater than previously thought of, and that the currently used recommendation has to be adjusted. The study clearly shows that the thicker the material, the greater the heat affected zone, independently of the steel type, since the thicker material takes longer time to cut.

Småskalig biobränsleeldad kraftvärmeproduktion : teknik och investeringsutrymme

To achieve the requirements to decrease emissions of greenhouse gases by 20 % by 2020, Swedenneeds to increase its use of bioenergy. In doing so it seems natural that those who already haveaccess to large amounts of biofuels in the form of by-products such as straw, wood chips anddigestible materials take advantage of these assets locally. By combining production of heat withpower production at the farm it may be possible to not only reduce the direct use of fossil fuel forheating but also reduce energy costs.The purpose was to simulate different cases of using a small scale biofueled combined heat andpower plant for farm-based systems. A MatLab-model was developed and used to draw conclusionsabout the costs for production of heat and electricity with different conversion technologies.The model uses climate data to simulate the variations in heat energy demand on a day-to-day basis.The given heat demand is the base of the simulation and from this the possible electric output iscalculated. This study has focused on the impact of the following properties: electric-, heat- andtotal efficiency, fuel, fuel price and specific fuel requirements.

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.

Studie av skyddsavstånd mellan bergvärmeanläggning och skyddsobjekt i ett vattenskyddsområde

During installation and operation of a geothermal heat pump system leakage of an antifreezing agent can appear in a borehole and leak out in surrounding groundwater. To guarantee high quality drinking water for generations to come Sweden has dedicated some areas as water protection areas. The local authority gives permits for the installation of heat pump systems within water protection areas. Before giving a permit the local authority makes an evaluation of the risks involved in installation and operation of the system within the area. By keeping a certain distance between the protected object in the area and the heat pump system the risk of polluting the protected object with an anti-freezing agent can be reduced.This thesis makes a comparison between three different methods of calculating an appropriate distance between the protected object and the heat pump system.

Energianalys av Svensk Växtkrafts biogasanläggning i Västerås

Svensk Växtkraft is the owner of the biogas plant in Västerås. The company is planning to increase their treatment capacity at their biogas plant. In connection to this work it is also possible to make some energy saving changes to the biogas plant. The objective of this study was therefore to make an electricity and heat survey of the biogas plant, a detailed study of the heat consumption in the sanitation step and also a comparison of energy consumption with the present sanitation method and an alternative strategy where the waste is treated in 55 °C during 10 hours (the current method is heating to 70 °C during 1 hour). The energy survey was conducted in close collaboration with staff at the biogas plant. The current during normal operation was measured, power was calculated and multiplied by the time of usage to obtain the energy consumed.

Imageination: En uppsats om imageöverföring inom sponsring och Event Marketing

There are two main reasons for why companies engage in sponsoring and Event Marketing; affecting the brand awareness and/or the image of the brand. Historically the main focus within the research field has been on how sponsoring and Event Marketing can create and achieve high brand awareness. More research regarding the image transfer from event to brand has been requested and this study is to be considered as an attempt to begin filling this gap. Today we see more and more brands choosing to arrange their own events; hoping to attain a more direct connection between the event and the brand. This trend raises questions such as - Do brands arranging their own events receive more image transfer from event to brand compared to brands sponsoring the same kind of event? - Are there any differences between an established well-known brand and a new unknown brand? - Will an event fully owned by a brand attract more or less people than an event arranged by someone considered to be less biased? These are some of the questions asked and answered within this thesis.

Energy analysis of a fruit drying plant in Adeiso, Ghana

The purpose of the project has been to work out recommendations that reduce the energy-related costs and environmental impact of HPW Fresh & Dry Ltd., a fruit drying factory in Ghana. The factory produces electricity with diesel and biogas but also purchases electricity from the national electricity company. Heat for the drying process is produced from biogas, kerosene and solar panels. In the project the energy system was analyzed by measuring production and consumption of heat and electricity. The project results show that the factory can become self-sufficient on heat if the available energy is used more efficient. The production units for both electricity and heat have low efficiencies.

Planering och projektering för individuell mätning och debitering i flerbostadshus

The study aims to reduce energy consumption in apartment buildings where individual metering and charging of heat is applied. The aim is to develop planning and design for individual metering and charging in apartment buildings.The study is based on literature review, interviews and case study that include analysis of existing documents. Interviews were carried out with the property developer and the involved consultants who planned the apartment building Yasuragi. To investigate the differences the condominium association has noted in heat consumption between flats, the debit values of the heat were used to discern which houses that were furthest from the average consumption. On these flats there were temperature measurements and thermal photo shoots made for discriminating behavior and possible construction techniques which could be the explanation for the heat spread.Boverket shows that the consumption of heat can be reduced by 10-20% after insertion of individual metering and charging in an apartment block.

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