| 1. |
- Bales, Chris, et al.
(author)
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TCA Evaluation : Lab Measurements, Modelling and System Simulations
- 2005
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Reports (other academic/artistic)abstract
- The study reported here is part of a large project for evaluation of the Thermo-Chemical Accumulator (TCA), a technology under development by the Swedish company ClimateWell AB. The studies concentrate on the use of the technology for comfort cooling. This report concentrates on measurements in the laboratory, modelling and system simulation. The TCA is a three-phase absorption heat pump that stores energy in the form of crystallised salt, in this case Lithium Chloride (LiCl) with water being the other substance. The process requires vacuum conditions as with standard absorption chillers using LiBr/water. Measurements were carried out in the laboratories at the Solar Energy Research Center SERC, at Högskolan Dalarna as well as at ClimateWell AB. The measurements at SERC were performed on a prototype version 7:1 and showed that this prototype had several problems resulting in poor and unreliable performance. The main results were that: there was significant corrosion leading to non-condensable gases that in turn caused very poor performance; unwanted crystallisation caused blockages as well as inconsistent behaviour; poor wetting of the heat exchangers resulted in relatively high temperature drops there. A measured thermal COP for cooling of 0.46 was found, which is significantly lower than the theoretical value. These findings resulted in a thorough redesign for the new prototype, called ClimateWell 10 (CW10), which was tested briefly by the authors at ClimateWell. The data collected here was not large, but enough to show that the machine worked consistently with no noticeable vacuum problems. It was also sufficient for identifying the main parameters in a simulation model developed for the TRNSYS simulation environment, but not enough to verify the model properly. This model was shown to be able to simulate the dynamic as well as static performance of the CW10, and was then used in a series of system simulations. A single system model was developed as the basis of the system simulations, consisting of a CW10 machine, 30 m2 flat plate solar collectors with backup boiler and an office with a design cooling load in Stockholm of 50 W/m2, resulting in a 7.5 kW design load for the 150 m2 floor area. Two base cases were defined based on this: one for Stockholm using a dry cooler with design cooling rate of 30 kW; one for Madrid with a cooling tower with design cooling rate of 34 kW. A number of parametric studies were performed based on these two base cases. These showed that the temperature lift is a limiting factor for cooling for higher ambient temperatures and for charging with fixed temperature source such as district heating. The simulated evacuated tube collector performs only marginally better than a good flat plate collector if considering the gross area, the margin being greater for larger solar fractions. For 30 m2 collector a solar faction of 49% and 67% were achieved for the Stockholm and Madrid base cases respectively. The average annual efficiency of the collector in Stockholm (12%) was much lower than that in Madrid (19%). The thermal COP was simulated to be approximately 0.70, but has not been possible to verify with measured data. The annual electrical COP was shown to be very dependent on the cooling load as a large proportion of electrical use is for components that are permanently on. For the cooling loads studied, the annual electrical COP ranged from 2.2 for a 2000 kWh cooling load to 18.0 for a 21000 kWh cooling load. There is however a potential to reduce the electricity consumption in the machine, which would improve these figures significantly. It was shown that a cooling tower is necessary for the Madrid climate, whereas a dry cooler is sufficient for Stockholm although a cooling tower does improve performance. The simulation study was very shallow and has shown a number of areas that are important to study in more depth. One such area is advanced control strategy, which is necessary to mitigate the weakness of the technology (low temperature lift for cooling) and to optimally use its strength (storage).
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| 2. |
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| 8. |
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| 9. |
- Delbro, Dick, et al.
(author)
-
Nuclear expression of mu-opioid receptors in a human mesothelial cell line
- 2009
-
In: Autonomic & Autacoid Pharmacology. - : Wiley. - 1474-8665 .- 1474-8673. ; 29:4, s. 165-170
-
Journal article (peer-reviewed)abstract
- 1 Possibly acting via mu-opioid receptors (MORs), morphine inhibits the formation ofexperimentally induced postoperative abdominal adhesions in rats. Mesothelial cells mayparticipate in adhesion formation by secreting mediators that interfere negatively withfibrinolysis. Morphine may prevent adhesions by inhibiting the release of pro-adhesionmediators from mesothelial cells. This study aimed to investigate whether human mesothelialcells express MOR-1; if so, such could constitute a site of action for morphine in adhesionprevention.2 Cells from Met-5A, a human mesothelial cell line were seeded and prepared forimmunocytochemistry and Western blotting.3 Immunocytochemistry showed MOR-1 expression in mesothelial cells, predominantly in thenuclei. Western blotting showed two bands (c. 35 and 50 kDa) which correspond to thoseobtained with a control lysate from cells known to express MORs. In addition, we foundMOR-1 expression with nuclear and cytoplasmatic localization in biopsies from humanabdominal adhesions.4 The current findings may suggest that morphine could interact directly with mesothelial cellsvia MOR-1 receptors, and thereby modulate adhesion formation, possibly by interfering withthe release of pro-adhesion factors from these cells
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| 10. |
- Fiedler, Frank, et al.
(author)
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Comparison of carbon monoxide emissions and electricity consumption of modulating and non-modulating pellet and solar heating systems
- 2007
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In: International Journal of Energy Research. - : Hindawi Limited. - 0363-907X .- 1099-114X. ; 31:10, s. 915-930
-
Journal article (peer-reviewed)abstract
- Emission and electricity consumption are important aspects of a pellet heating system. Low noxious emissions, particularly carbon monoxide, are a measure of a well-performing system. High carbon monoxide emissions are often caused by unnecessary cycling of the burner, poor adjustment of the combustion air and insufficient maintenance. The carbon monoxide output, the thermal performance and the electricity consumption for modulating and non-modulating operation mode have been investigated by simulations of four stoves/boilers as part of combined solar and pellet heating systems. The systems have been modelled with the simulation programme TRNSYS and simulated with the boundary conditions for space heating demand, hot water load and climate data as used in earlier research projects. The results from the simulations show that operating the pellet units with modulating combustion power reduces the number of starts and stops but does not necessarily reduce the carbon monoxide output. Whether the carbon monoxide output can be reduced or not depends very strongly on the reduction of starts and stops and how much the carbon monoxide emissions increase with decreased combustion power, which are in turn dependent on the particular settings of each pellet burner and how the heat is transferred to the building. However, for most systems the modulating operation mode has a positive impact on carbon monoxide emissions. Considering the total auxiliary energy demand, including the electricity demand of the pellet units, the modulating combustion control is advantageous for systems 1 and 4 for the used boundary conditions. The study also shows that an appropriate sizing of the stove or boiler has a huge potential for energy saving and carbon monoxide emission reduction.
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| 11. |
- Fiedler, Frank, et al.
(author)
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Heat losses and thermal performance of commercial combined solar and pellet heating systems
- 2004
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In: Eurosun 2004. - Freiburg/Germany.
-
Conference paper (other academic/artistic)abstract
- Various pellet heating systems are marketed in Sweden, some of them in combination with a solar heating system. Several types of pellet heating units are available and can be used for a combined system. This article compares four typical combined solar and pellet heating systems: System 1 and 2 two with a pellet stove, system 3 with a store integrated pellet burner and system 4 with a pellet boiler. The lower efficiency of pellet heaters compared to oil or gas heaters increases the primary energy demand. Consequently heat losses of the various systems have been studied. The systems have been modeled in TRNSYS and simulated with parameters identified from measurements. For almost all systems the flue gas losses are the main heat losses except for system 3 where store heat losses prevail. Relevant are also the heat losses of the burner and the boiler to the ambient. Significant leakage losses are noticed for system 3 and 4. For buildings with an open internal design system 1 is the most efficient solution. Other buildings should preferably apply system 3. The right choice of the system depends also on whether the heater is placed inside or outside of the heated are. A large potential for system optimization exist for all studied systems, which when applied could alter the relative merits of the different system types.
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| 12. |
- Fiedler, Frank, et al.
(author)
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Thermal performance of combined solar and pellet heating systems
- 2006
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In: Renewable energy. - : Elsevier BV. - 0960-1481 .- 1879-0682. ; 31, s. 73-88
-
Journal article (peer-reviewed)abstract
- Various pellet heating systems are marketed in Sweden, some of them in combination with a solar heating system. Several types of pellet heating units are available and can be used for a combined system. This article compares four typical combined solar and pellet heating systems. System 1 and 2 with a pellet stove, system 3 with a store integrated pellet burner and system 4 with a pellet boiler. The often lower efficiency of pellet heaters compared to oil or gas heaters increases the final energy demand. Consequently, heat losses of the various systems have been studied. The systems have been modeled in TRNSYS and simulated with parameters identified from measurements. For almost all systems the flue gas losses are the main heat losses except for system 3 where store heat losses prevail. Relevant are also the heat losses of the burner and the boiler to the ambient. Significant leakage losses are noticed for system 3 and 4. For buildings with an open internal design system I is the most efficient solution. Other buildings should preferably apply system 2 or 3. The right choice of the system depends also on whether the heater is placed inside or outside of the heated area. Unlike the expectations and results from other studies, the operation of the pellet heaters with modulating combustion power is not necessarily improving the performance. A large potential for system optimisation exists for all studied systems, which when applied could alter the relative merits of the different system types
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| 13. |
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| 14. |
- Ma, Fei, et al.
(author)
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Ultrafast excited state dynamics of [Cr(CO)4(bpy)] : Revealing the relaxation between triplet charge-transfer states
- 2016
-
In: RSC Advances. - : Royal Society of Chemistry (RSC). - 2046-2069. ; 6:25, s. 20507-20515
-
Journal article (peer-reviewed)abstract
- Ultrafast excited state dynamics of [Cr(CO)4(bpy)] upon metal-to-ligand charge-transfer (1MLCT) transition have been studied by pump-probe absorption spectroscopy in CH3CN, pyridine and CH2Cl2 solvents. Intersystem crossing (ISC) was found to be very fast (∼100 fs) and efficient, while the formation of the photoproduct with one axial CO dissociated is significantly less competitive, indicating a barrier along the dissociative coordinate. As a refinement of the previous dynamic model [I. R. Farrell, et al., J. Am. Chem. Soc., 1999, 121, 5296-5301], we show that a conventional downhill energy relaxation concept dominates the observed dynamics. Experimentally, we have identified the consecutive population of two triplet states as a result of triplet electronic relaxation convoluted with vibrational and solvent relaxation (the overall time is 2.7-6.9 ps depending on solvent), as well as the overall depopulation of the excited state through the lowest triplet state (57-84 ps). Adaptive excitation pulse shaping could not achieve optimization of the photoproduct quantum yield via re-distribution of only low-frequency vibrational modes during excitation, indicating that the two low-lying 1MLCT states, Cr(3d) → π∗bpy and Cr(3d) → π∗CO, are not coupled.
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| 15. |
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| 16. |
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| 17. |
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| 18. |
- Nordlander, Svante, et al.
(author)
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Computer modelling of wood pellet stoves and boilers connected to solar heating systems
- 2006
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In: Proc on USB of Pellets 2006, 30 May - 1 June, Jönköping, Sweden. - Jönköping, Sweden.
-
Conference paper (other academic/artistic)abstract
- When optimizing systems for wood pellet and solar heating, there is a need for realistic computer models of stoves and boilers in order to perform simulation studies. The objective of this work was to develop and verify a mathematical model for wood pellet stoves and boilers for use in system simulations with TRNSYS calculating both the energy balance and CO-emissions (carbon monoxide). Laboratory measurements have been carried out on three pellet stoves, one traditional and two with gas-liquid heat exchangers, and four pellet boilers. A mathematical two-node model of a stove was developed and implemented as a TRNSYS component. Parameters were identified for two stoves and three boilers. This new model makes it possible to perform detailed simulations with time steps less than a minute of complete wood pellet heating systems and to derive long term values, such as annual values, of efficiency and emissions for the boiler or stove in a system context under realistic conditions. In addition, parametric studies can be used in order to investigate how different operation principles and system design affect these values. The simulated energy balance of a water jacketed stove investigated in this work agreed well with measured data during both stationary and dynamic conditions.
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| 19. |
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| 20. |
- Nordlander, Svante, et al.
(author)
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Evaluation and computer modelling of wood pellet stoves with liquid heat exchangers
- 2003
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In: presented at ISES Solar World Congress. - Göteborg, Sweden.
-
Conference paper (other academic/artistic)abstract
- The pellet consumption for single family house heating in Sweden is increasing strongly. Pellet stoves and boilers for domestic heating are becoming increasingly popular and new stove models with gas-liquid heat exchangers have entered the market. There is a need for computer models of the stoves, in order to perform simulation studies. The objective of this work was to evaluate pellet stoves and to make mathematical models of them for use in simulations of heating systems with TRNSYS. Three pellet stoves, one traditional and two with gas-liquid heat exchangers, and one pellet burner were tested in a combustion laboratory. A mathematical two-node model of a stove was developed and implemented as a TRNSYS component. A number of heat transfer coefficients and thermal masses of the stoves were identified. The calculated performance of the stoves agreed well with the measured data. The stove model was used in extensive TRNSYS simulations of yearly performance of single-family house heating systems. The simulations showed that the emissions, the yearly efficiency of a stove and the savings of auxiliary electric energy for heating may vary significantly depending on system design and control strategy.
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| 21. |
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| 22. |
- Nordlander, Svante
(author)
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Load Adapted Solar Thermal Combisystems - Optical Analysis and Systems Optimization
- 2004
-
Licentiate thesis (other academic/artistic)abstract
- In a northern European climate a typical solar combisystem for a single family house normally saves between 10 and 30 % of the auxiliary energy needed for space heating and domestic water heating. It is considered uneconomical to dimension systems for higher energy savings. Overheating problems may also occur. One way of avoiding these problems is to use a collector that is designed so that it has a low optical efficiency in summer, when the solar elevation is high and the load is small, and a high optical efficiency in early spring and late fall when the solar elevation is low and the load is large.The study investigates the possibilities to design the system and, in particular, the collector optics, in order to match the system performance with the yearly variations of the heating load and the solar irradiation. It seems possible to design practically viable load adapted collectors, and to use them for whole roofs ( 40 m2) without causing more overheating stress on the system than with a standard 10 m2 system. The load adapted collectors collect roughly as much energy per unit area as flat plate collectors, but they may be produced at a lower cost due to lower material costs. There is an additional potential for a cost reduction since it is possible to design the load adapted collector for low stagnation temperatures making it possible to use less expensive materials. One and the same collector design is suitable for a wide range of system sizes and roof inclinations. The report contains descriptions of optimized collector designs, properties of realistic collectors, and results of calculations of system output, stagnation performance and cost performance. Appropriate computer tools for optical analysis, optimization of collectors in systems and a very fast simulation model have been developed.
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| 23. |
- Nordlander, Svante, et al.
(author)
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Load and Season Adapted Solar Collectors
- 2000
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In: Eurosun 2000. - Copenhagen, Denmark.
-
Conference paper (other academic/artistic)abstract
- In Sweden solar irradiation and space heating loads are unevenly distributed over the year. Domestic hot water loads may be nearly constant. Test results on solar collector performance are often reported as yearly output of a certain collector at fixed temperatures, e g 25, 50 and 75 C. These data are not suitable for dimensioning of solar systems, because the actual performance of the collector depends heavily on solar fraction and load distribution over the year. At higher latitudes it is difficult to attain high solar fractions for buildings, due to overheating in summer and small marginal output for added collector area. Solar collectors with internal reflectors offer possibilities to evade overheating problems and deliver more energy at seasons when the load is higher. There are methods for estimating the yearly angular irradiation distribution, but there is a lack of methods for describing the load and the storage in such a way as to enable optical design of season and load adapted collectors. This report describes two methods for estimation of solar system performance with relevance for season and load adaption. Results regarding attainable solar fractions as a function of collector features, load profiles, load levels and storage characteristics are reported. The first method uses monthly collector output data at fixed temperatures from the simulation program MINSUN for estimating solar fractions for different load profiles and load levels. The load level is defined as estimated yearly collector output at constant collector temperature divided be yearly load. This table may examplify the results: Collector Load Load Solar Improvement type profile level fraction over flat plate Flat plate DHW 75 % 59 % Load adapted DHW 75 % 66 % 12 % Flat plate Space heating 50 % 22 % Load adapted Space heating 50 % 28 % 29 % The second method utilises simulations with one-hour timesteps for collectors connected to a simplified storage and a variable load. Collector output, optical and thermal losses, heat overproduction, load level and storage temperature are presented as functions of solar incidence angles. These data are suitable for optical design of load adapted solar collectors. Results for a Stockholm location indicate that a solar combisystem with a solar fraction around 30 % should have collectors that reduce heat production at solar heights above 30 degrees and have optimum efficiency for solar heights between 8 and 30 degrees.
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| 24. |
- Nordlander, Svante
(author)
-
Maximum concentration for ideal asymmetrical radiation concentrators
- 2005
-
In: Solar Energy. - 0038-092X .- 1471-1257. ; 79:5, s. 566-567
-
Journal article (peer-reviewed)abstract
- A new relation between the maximum geometric concentration factor C and the angular acceptance interval for asymmetrical ideal non-imaging concentrators is proposed. A generalization of the well-known relation for the two-dimensional case, sin ?c = 1/C where ?c is the acceptance half-angle, results in the proposed relation sin ?2 -sin ?1 = 2/C , where ?1 and ?2 are the angles of the acceptance interval limits relative to the normal of the entrance aperture. The proposed relation is valid for any ideal 2D concentrator, symmetrical or asymmetrical. A proof based on conservation of phase space is provided.
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| 25. |
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| 26. |
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| 27. |
- Nordlander, Svante, et al.
(author)
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PRESIM - a graphical interactive preprocessor for modular simulation programs
- 1989
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In: ISES Solar World Congress. - Kobe, Japan.
-
Conference paper (peer-reviewed)abstract
- PRESIM is a computer program for creating, storing, retrieving and changing input data for modular HVAC programs. The user works with CAD-style tools. The program also produces system schematics and other documentation. A first release of PRESIM will produce input data for the TRNSYS program.
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| 28. |
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| 29. |
- Nordlander, Svante
(author)
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Ramprogram solfångarutveckling och systematik. FoU 1997-1999. Slutrapport BFR projekt 19960605
- 1999
-
Reports (other academic/artistic)abstract
- Man kan förbättra energibesparingen på årsbasis för ett traditionellt svenskt kombisolvärmesystem från knappt 20 % för ett referenssystem till över 25 %. Alla de studerade systemen har 10 m2 solfångare, lika stor tank, och samma värme- och tappvarmvattenlast. Skillnaderna består endast i systemutformning. Arbetet har utförts genom mätningar i värmelaboratorium och simuleringsberäkningar. Inom området optisk design av solenergisystem har metoder utvecklats för: - analys av solinstråningens himmelsfordelning och asymmetriska årsfordelning - optimering av sollangare med reflektorer - optimering av solceller med tillsatsreflektorer Programmet PRESIM, grafisk indatabehandlare till simuleringsprogrammet TRNSYS, har vidareutvecklats i linje med användarnas önskemål, men förutsättningarna för fortsatt utveckling har försämrats. En förbättrad version, delvis finansierad av Statens energimyndighet och anpassad till TRNSYS 15.0, kommer att släppas under år 2000, men därefter kommer aktiviteten att ligga på en lägre nivå.
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| 30. |
- Nordlander, Svante, et al.
(author)
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Solvärmesystem för hög täckningsgrad - Load adapted concentrating collectors for high solar fractions
- 2004
-
Reports (other academic/artistic)abstract
- Dagens kombisolvärmesystem för enfamiljshus har i storleksordningen 10 m2 solfångare och kan täcka i runda tal 10 ? 30 % av det årliga värmebehovet. Ökar man solfångarytan för att öka solvärmetäckningsgraden uppstår det vanligtvis en överproduktion av värme sommartid viket kan orsaka problem i form av termisk utmattning av material, att material förstörs eller att säkerhetsventiler utlöses med driftsstopp som följd. Vidare förkortas glykolens livslängd radikalt och detta kan ge följdskador såsom korrosion, beläggningar i rören och t o m igensättning av systemet. Ett sätt att undvika problemen med överhettning i solvärmesystem med hög täckningsgrad är att använda lastanpassade solfångare. Med detta menas solfångare som har en verkningsgrad som är beroende av solhöjden och varierar över året. Verkningsgraden är hög när värmelasten är hög (vanligtvis sen höst, vinter och tidig vår) medan verkningsgraden är låg då värmelasten är låg (vanligtvis sen vår, sommar och tidig höst). I denna rapport visas att det är möjligt att bygga lastanpassade solfångarsystem med hög täckningsgrad för enfamiljshus med solfångarytor som täcker hela villatak (>= 40 m2), utan att den termiska påfrestningen på systemet blir större än för vanliga solvärmesystem med 10 m2 plana solfångare. Detta kan göras med samma systemkomponenter som finns i system med plana solfångare. De lastanpassade solfångarna levererar ungefär samma energimängd per m2 som plana solfångare, men de bör kunna bli billigare, på grund av lägre materialkostnad. Det finns även en potential att konstruera lastanpassade solvärmesystem med begränsad stagnationstemperatur, vilket kan möjliggöra användandet av billigare material. En och samma solfångartyp är lämplig för såväl stora som små system och för olika takvinklar. I rapporten redovisas optimerade solfångargeometrier för lastanpassade solvärmesystem, geometrier och optiska egenskaper för praktiskt möjliga solfångare samt beräkningar av förväntat årsutbyte, stagnationstemperaturer, stagnationstider och kostnader. Testresultat för två prototyper av lastanpassade solfångare presenteras. Optimeringsalgoritmer för design av optiken för lastanpassade solfångare i system samt ett ray-tracingverktyg och snabba men ändå tillräckligt noggranna simuleringsverktyg har utvecklats.
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| 31. |
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| 32. |
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| 33. |
- Persson, Tomas, et al.
(author)
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Conversion of Electrically Heated Houses to Pellets and Solar
- 2003
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In: ISES Solar World Congress. - Göteborg, Sweden.
-
Conference paper (other academic/artistic)abstract
- This study investigates how electrically heated single-family houses can be converted to wood pellets- and solar heating using pellet stoves and solar heating systems. Four different system concepts are presented and system simulations in TRNSYS evaluate the thermal performance and the electrical savings possible for two different electrically heated buildings. Simulations show that the electricity savings using a pellet stove are greatly affected by the level of comfort, the house plan, the system choice and if the internal doors are open or closed. Installing a stove with a water-jacket connected to a radiator system and a hot water storage has the advantage that heat can be transferred to domestic hot water and be distributed to other rooms. Such systems leads to that more electricity can be replaced, especially in houses having a traditional plan. Though it is unnecessary to have too many radiators connected to a stove with a low fraction of energy heating the water jacket. Today’s most common control principle for stoves, (the ON-OFF control) results in unnecessarily high emissions. A more advanced control varying the heating rate from maximum to minimum to keep a constant room temperature reduces the number of starts and stops and thereby the emissions.
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| 34. |
- Persson, Tomas, et al.
(author)
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Electrical savings by use of wood pellet stoves and solar heating systems in electrically heated single-family houses
- 2005
-
In: Energy and Buildings. - : Elsevier BV. - 0378-7788 .- 1872-6178. ; 37:9, s. 920-929
-
Journal article (peer-reviewed)abstract
- This study investigates how electrically heated single-family houses can be converted to wood pellets- and solar heating using pellet stoves and solar heating systems. Four different system concepts are presented and system simulations in TRNSYS evaluate the thermal performance and the electrical savings possible for two different electrically heated single-family houses. Simulations show that the electricity savings using a wood pellet stove are greatly affected by the level of comfort, the house plan, the system choice and if the internal doors are open or closed. Installing a stove with a water-jacket connected to a radiator system and a hot water store has the advantage that heat can be transferred to domestic hot water and be distributed to other rooms. Such systems leads to that more electricity can be replaced, especially in houses having a traditional plan. Though it is unnecessary to have too many radiators connected to a stove with a low fraction of energy heating the water jacket. Today's most common control strategy for stoves (the on/off-control) results in unnecessarily high emissions. A more advanced control varying the heating rate from maximum to minimum to keep a constant room temperature reduces the number of starts and stops and thereby the emissions.
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| 35. |
- Persson, Tomas, et al.
(author)
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Validation of a dynamic model for wood pellet boilers and stoves
- 2009
-
In: Applied Energy. - : Elsevier. - 0306-2619 .- 1872-9118. ; :86
-
Journal article (peer-reviewed)abstract
- Optimising systems with wood pellet boilers or stoves using simulations requires realistic computer models. The objective of this work was to develop and verify a mathematical model for wood pellet boilers and stoves for use in system simulations with the dynamic simulation programme TRNSYS, calculating both the energy balance and the CO-emissions (carbon monoxide emissions). Laboratory measurements have been carried out and a mathematical two-node model was developed and implemented as a TRNSYS component. Parameters were identified and the model has been compared with measurements. The model shows in general good agreement with measured data, however there are details that could be improved. This involves improved modelling of the dynamic response for boilers with large water volumes and improved modelling of the air factor and the CO-emissions, especially during start and stop conditions. Further improved methodology and accuracy for measuring and parameter identification is recommended.
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| 36. |
- Pettersson, Ann, 1982-, et al.
(author)
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Expression of the endogenous, nicotinic acetylcholine receptor ligand, SLURP-1, in human colon cancer.
- 2008
-
In: Autonomic & Autacoid Pharmacology. - : Wiley. - 1474-8665 .- 1474-8673. ; 28:4, s. 109-116
-
Journal article (peer-reviewed)abstract
- 1. Secreted mammalian Ly-6/urokinase plasminogen activator receptor-related protein-1 (SLURP-1) is a recently discovered endogenous ligand at the alpha7 subunit of the nicotinic acetylcholine receptors. Previous reports have shown that SLURP-1 is expressed in normal human keratinocytes seemingly with a pro-apoptotic function. Conversely, such expression was markedly attenuated in transformed cells and it was suggested that the molecule could convey protection against malignant transformation. 2. In this study, we demonstrated the mRNA expression (by RT-PCR) and protein expression (by Western blotting and immunocytochemistry) of SLURP-1 in the human colon cancer cell line, HT-29. 3. Furthermore, we demonstrated the expression of SLURP-1 (by immunohistochemistry) in tumour cells of human colon cancer tissue, and, to a greater extent, in immune and smooth muscle cells of adjacent, macroscopically tumour-free colon tissue. 4. The current findings suggest that SLURP-1 participates in the regulation of gut immune functions and motility, as well as possibly playing a role in colon carcinogenesis/cancer progression.
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| 37. |
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