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435 Uppsatser om Thermal fatigue - Sida 5 av 29

Temperaturzoner för lagring av värmeenergi i cirkulärt borrhålsfält

The thermal response of a borehole field is often described by non?dimensional response factors called gfunctions.The g?function was firstly generated as a numerical solution based on SBM (Superposition BoreholeModel). An analytical approach, the FLS (Finite Line Source), is also accepted for generating the g?function. In thiswork the potential to numerically produce g?functions is studied for circular borehole fields using the commercialsoftware COMSOL.

Inverkan av stora mängder halm som underlag i grisningsboxen på den nyfödda smågrisens temperaturreglering :

The aim of the present study was to evaluate the effects of large amounts of straw in the farrowing pen on thermal regulation of the newborn piglet in different weight classes. 20 sows were given 15 kg of straw in the farrowing pen 2 days prior to until 7 days after parturition. A control group of 18 sows had no straw in the pen. 6 litters from each treatment were observed. Measurements of piglet body temperature were made at 0h, 2h, 4h, 8h and 24h after parturition. At ?8h? the body temperature of the piglets in the Straw group were significantly higher (P=0,0149) than the piglets in the Control group.

Styrsystem : För en forskningsutrustning

The division of Engineering Materials at Linköping University, department of Management and Engineering, conducted a research project concerning Fatigue life of thermal barrier coatings during 2009. During this project equipment to provoke these fatigue failure by rapidly heating and cooling test subjects in cycles, was ordered.Design and manufacturing of the equipment was handled internally at LIU.The equipment was built using a furnace that is lowered and raised over the table where the test subject is placed. To keep the temperature of the furnace a lid slides in place to close the downward facing opening of the furnace when it is in the raised position. On this door there is nozzle that is used to cooling of the test subject by air.To make sure that the equipment can work independently you need an automation controller that can evaluate if movement can occur without danger of collisions. The control system also needs to monitor that all elements are performed according to plan.This degree project is based on a modular system from OPTO 22 and includes the configuration of a PLC that will be supplied with logic and a user interface.The degree project resulted in a graphic interface in which a user can set desired values for different parameters and get information about current values for them.

Skattning av biverkningar : Sjuksköterske- och patientuppfattning om behandlingsrelaterade biverkningar vid stamcellstransplantation.

A possible treatment for patients with lymphoma and myeloma is stem cell transplantation (SCT). SCT is preceded with cytostatic treatment. There are several side effects related to this treatment, for example fatigue, nausea, constipation/diarrhoea, pain, mucositis and loss of appetite. Aim: Investigate which side effects related to the treatment where most troubling after SCT and if nurse assessment and patient assessment differ. Methods: A quantitative empirical study with repeated measuring.

Påverkan på energianvändning och termisk komfort vid reglerinstabilitet

The purpose of the study is to investigate the possible effects of an unstable ventilation system and its influence on energy use and thermal comfort. The report also explores how qualified personal working with HVAC view and handles system control.In order to meet the requirements in energy efficiency and a comfortable indoor climate control regulation is a prerequisite. With optimized increased complexity of the climate systems, it becomes more challenging to control the system and the risk of unstable control increases. No previous studies about what affect an unstable system can have on energy use and thermal comfort have been found.The report is based on several tests were the controlling variable has been increased until the system becomes unstable. Two different types of unstable systems have been investigated.

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.

Jämförelse mellan BKR/BSK och Eurokoders behandling av utmattning i traversbalkar med tillhörande svetsfogar

This report has been performed for WSP Construction Design located at Arenavägen 7 in Stockholm. WSP Construction Design is one of the leading departments in Sweden in construction solutions regarding everything from building construction to industrial building. Great competencies regarding steel, wood and concrete constructions are available within the department which is well sought.Crane girders used in the industry are exposed to large loads that vary over time that includes instantaneous lifts and the crane girders movement which lead to the phenomenon fatigue in the crane girder and its ingoing welds. A control of fatigue needs to be performed after a certain lifespan measured in time which in turn is converted to a number of loadcycles. When the number of loadcycles amounts to a greater number the input welds resistance will have been reduced and the rate of utilization thereby increased.

Värmeförluster vid utvändigt placerade ventilationssystem

To be able to handle tomorrows need for limited energy consumption we need to reduce our use of energy. The building sector stands for around 40 % of all energy consumption in the society. The government has put up a goal to reduce the energy consumption in our buildings with 20 % by year 2020 and 50 % by year 2050 compared with year 1995. To be able to do reach that goal we need a more energy efficient building stock.The main part of the energy used in our buildings is used for space heating. By installing ventilation systems with heat recovery on the exhaust air it is possible to use the heat-energy in the exhaust air to warm up the incoming air.

Köldbryggor och energiförluster. En studie om energiförluster genom balkonginfästningar och deras betydelse för byggnadens totala energibehov

In this report the balconies? abutments for a property in Bo01-area in Malmö has been studied. The property which is called Vitruvius contains four build-ings where two of them have corbelling balconies with intermittent abutments. With intermittent abutment means that the 50 mm thermal bridge insulation that the balconies is equipped with, is broken regularly by a 300 mm concrete heel. The reinforcement bar that holds the balcony runs through this heel.

Kartläggning av OFP och defektrelaterade parametrar : Inriktning på termisk utmattning

I både kvalitets- och kontrollarbete finns det behov att kunskapsmässigt komma så nära verkligheten som möjligt vid fastställande av defektparametrar för oförstörande provning (OFP). Orsaken är att olika acceptanskrav och bedömningsgränser är svåra att klarlägga när man inte kan förlita sig på att uppgifter är realistiska. I projektet har olika erfarenheter använts för att få en bättre helhetsbild i området för defektparametrar och oförstörande provning.Denna rapport redovisar den inledande delen av forskning och utvecklingsprojektet PLANT 2, där olika defektparametrar kartlagts och en teoretisk bedömning utförts med avseende på hur signalsvaret påverkas för OFP-metoderna virvelström (ET) och ultraljudsprovning (UT) i form av puls-eko (PE) och ?time-of-flight-diffraction? (TOFD).Definitionen av redovisade defektparametrar följer i stort SKI-rapport 95:70 [1]. Defektparametrar i denna rapport redovisas i bilaga 1.Vid bedömningen av defektparametrarnas inverkan på OFP-tekniker, har drift¬inducerande defekter och tillverkningsdefekter hanterats separat.

Kartläggning av OFP och defektrelaterade parametrar : Inriktning på termisk utmattning

I både kvalitets- och kontrollarbete finns det behov att kunskapsmässigt komma så nära verkligheten som möjligt vid fastställande av defektparametrar för oförstörande provning (OFP). Orsaken är att olika acceptanskrav och bedömningsgränser är svåra att klarlägga när man inte kan förlita sig på att uppgifter är realistiska. I projektet har olika erfarenheter använts för att få en bättre helhetsbild i området för defektparametrar och oförstörande provning.Denna rapport redovisar den inledande delen av forskning och utvecklingsprojektet PLANT 2, där olika defektparametrar kartlagts och en teoretisk bedömning utförts med avseende på hur signalsvaret påverkas för OFP-metoderna virvelström (ET) och ultraljudsprovning (UT) i form av puls-eko (PE) och ?time-of-flight-diffraction? (TOFD).Definitionen av redovisade defektparametrar följer i stort SKI-rapport 95:70 [1]. Defektparametrar i denna rapport redovisas i bilaga 1.Vid bedömningen av defektparametrarnas inverkan på OFP-tekniker, har drift¬inducerande defekter och tillverkningsdefekter hanterats separat.

Patienters upplevelse av cancerrelaterad fatigue, diarré och illamående under behandling av kolorektalcancer : en litteraturstudie

Kolorektalcancer är den tredje mest förekommande cancerformen i Sverige. Patienter med kolorektalcancer upplever mellan 8-10 symtom under sin sjukdomstid. Syftet: Med utgångspunkt från Lenz et al. (1997) symtomteori, ?The middle-range theory of unpleasent symptoms: An update? var syftet med litteraturstudien att utifrån ett patientperspektiv studera upplevelse av symtomen cancerrelaterad fatigue, diarré och illamående samt påverkansfaktorer och dess konsekvenser under behandling av kolorektalcancer.

TILLFÄLLIGA EFFEKTTOPPAR I FJÄRRVÄRMEN : Kan man med hjälp av lagrad värme undvika att de uppstår i betonghus?

Climate and environmental issues is now high on the agenda. We live in a generation that must try to solve some major environmental problems. Buildings and habitations account for approximately 40 % of Sweden's total energy today. To reduce this figure, as needed, more research in the field of energy efficiency is required.This thesis concerns the heating of buildings. The load on district heating is heavy during certain times of the day.

MOLNU : Att utveckla ett gemensamt gränssnitt

Climate and environmental issues is now high on the agenda. We live in a generation that must try to solve some major environmental problems. Buildings and habitations account for approximately 40 % of Sweden's total energy today. To reduce this figure, as needed, more research in the field of energy efficiency is required.This thesis concerns the heating of buildings. The load on district heating is heavy during certain times of the day.

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.

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