Previous to the now acting construction regulations EKS and Eurocode, the fire resistance of the load-bearing structures of mono glazed balconies were designed with a fire test called the SP fire 105. In 2011, when EKS replaced the previous construction regulations called Boverkets konstruktionsregler, BKR, the SP fire 105 was no longer the requirement for mono glazed balconies. Instead, EKS prescribed that the load-bearing structures of mono glazed balconies should be determined by the use of nominal fire exposure or a natural fire model. EKS and Eurocode have previously prescribed that the standard temperature-time curve (ISO 834) was to be used when determining the fire resistance of structural elements according to nominal temperature-time curves. But an agreement made between Balkongföreningen and Boverket in 2011, established that the external temperature-time curve could be used for determination of the fire resistance of the structural elements of mono glazed balconies. The external temperature-time curve means a design temperature of the structural members of approximately 680 °C for a fire-resistance class R30, instead of a temperature of 842 °C for the standard temperature-time curve. In 2019, EKS 11 was introduced with a slight change in the regulation. The new regulation specifically implies that building parts placed within glazed balconies should not be considered as external. Due to the formulation in EKS 11, it is no longer possible to use the external temperature-time curve for verification of the fire resistance of structural elements of mono glazed balconies. The formulation says that building parts placed within glazed balconies should not be considered as external, which means that the standard temperature-time curve must be applied. The present research tries to clarify the more reasonable temperature-time curve of the standard fire curve and the external fire curve, or if neither of the curves is realistic. 16 scenarios were analysed in this study. Using CFD simulations in FDS, the adiabatic surface temperature of the structural parts could be established. The adiabatic surface temperatures were then used as input in the FEM calculation program TASEF to calculate the temperatures of structural elements of a mono glazed balcony during a fire. The results imply that the max temperatures of the steel members of the mono glazed balcony analysed are generally lower than the temperatures of the external temperature-time curve. In a worst-case scenario where the structural member is located just adjacent to the fire source, the max temperature can be higher than the temperature of the standard temperature-time curve. The balcony slab reaches max temperatures between the external temperature-time curve and the standard temperature-time curve. The temperature within the slab is below 500 °C at a depth of 15 mm and according to the 500 °C isotherm method presented in SS-EN 1992-1-2, concrete that has a temperature lower than 500 °C has not been damaged by the fire. Further studies are needed to establish whether the external temperature-time curve or the standard temperature-time curve is to be used when designing the fire resistance of the load-bearing structure of mono glazed balconies. A suggestion for further studies is to conduct fire tests of a fire within a mono glazed balcony. Such results could then be compared to the results of this study and hopefully, lead to conclusions that are needed for a complete establishment of which temperature-time curve that should be used. / Under det tidigare gällande regelverket boverkets konstruktionsregler, BKR, dimensionerades brandmotståndet för den bärande konstruktionen av enkelinglasade balkonger med testmetoden SP fire 105. När BKR ersattes av boverkets föreskrifter och allmänna råd om tillämpning av europeiska konstruktionsstandarder, EKS, tillsammans med Eurokoderna, slutade man att använda SP fire 105 och började istället använda nominella temperatur-/tidförlopp. I tidigare versioner av EKS föreskrevs det att dimensionering enligt klassificering ska utföras med en brandexponering enligt standardtemperatur/-tidkurvan (ISO 834). Men i och med upphörandet av BKR år 2011, genomfördes en överenskommelse mellan Balkongförening och Boverket där man bestämde att den bärande konstruktionen för enkelinglasade balkonger och öppna balkonger skulle få dimensioneras med exponeringskurvan för utvändig brand istället för standardtemperatur-/tidkurvan. Dimensionering enligt exponeringskurvan för utvändig brand resulterar i en dimensionerande temperatur på 680 °C för brandteknisk klass R30, istället för en temperatur på 842 °C vid dimensionering med standardtemperatur-/tidkurvan. Vid införandet av EKS 11 år 2019 skedde en förändring i föreskrifterna gällande branddimensionering av bärande konstruktioner. I EKS 11 framgår det explicit att byggnadsdelar vilka är placerade inom inglasade balkonger inte bör betraktas som utvändiga byggnadsdelar. Detta medför att den bärande konstruktionen för enkelinglasade balkonger inte längre kan dimensioneras enligt exponeringskurvan för utvändig brand, utan måste dimensioneras enligt standardtemperatur-/tidkurvan. Denna studie syftar till att klargöra vilken temperatur som är rimlig att använda vid dimensionering av den bärande konstruktionen för enkelinglasade balkonger. Är den tidigare exponeringskurvan för utvändig brand mer rimlig, eller är föreskriften om att använda standardtemperatur-/tidkurvan motiverad? I studien har 16 scenarion analyserats med hjälp av CFD beräkningar i simuleringsprogrammet FDS, och med hjälp av FEM beräkningar i simuleringsprogrammet TASEF. Med FDS beräknades den adiabatiska yttemperaturen för den bärande konstruktionen, vilken sedan användes som indata i TASEF för att beräkna temperaturen i den bärande konstruktionen. Maxtemperaturen på konstruktionselementen som utgörs av stål uppnår generellt temperaturer som understiger temperaturen för exponeringskurvan vid utvändig brand. I ett ”worst-case” scenario där brandkällan står i direkt anslutning till en stålkonstruktion, kan temperaturer uppnås vilka överstiger temperaturen i standardtemperatur-/tidkurvan. Maxtemperaturen på balkongplattan är högre än temperaturen i exponeringskurvan vid utvändig brand, men lägre än temperaturen i standardtemperatur-/tidkurvan. 15 mm in i balkongplattan understiger temperaturen på betongen 500 °C. Enligt 500 °C isotermmetoden som är publicerad i SS-EN 1992-1-2 innebär detta förenklat att all betong på ett djup överstigande 15 mm har kvar sin fulla bärförmåga. En slutsats är att det krävs vidare studier för att kunna fastställa vilket nominellt temperatur-/tidförlopp som borde användas vid dimensionering av den bärande konstruktionen för enkelinglasade balkonger. Ett förslag på vidare studier är att utföra brandtester på en enkelinglasad balkong, varav resultaten sedan kan jämföras med resultaten i denna studie. Sådana resultat skulle förhoppningsvis möjliggöra ett fastställande av vilket nominellt temperatur-/tidförlopp som bör användas vid dimensionering av den bärande konstruktionen för enkelinglasade balkonger.

FDS (Fire Dynamics Simulator) använder en version av Navier-Stokes ekvationerna för att göra noggranna beräkningar av värme- och gastransport genom brandbelastade utrymmen. Utvecklarna av programmet arbetar kontinuerligt med att validera det allteftersom nya funktioner tillförs för att öka noggrannheten och bredda tillämpningsområdena. Väldigt lite av detta arbete fokuserar dock på FDS:s konduktionsmodell, den endimensionella Crank-Nicolson metoden. Det här examensarbetet ämnar därför undersöka noggrannheten i FDS:s konduktionsmodell genom jämförelse mot beräkningar med FEM (Finita elementmetoden). En FDS-modell skapades för att tillåta undersökning av en vägg och dess randvillkor med så liten påverkan från andra faktorer som möjligt. Detta för att skapa en kontrollerad omgivning som enkelt kunde replikeras i efterföljande FE-beräkningar av det konduktiva värmeflödet genom den solida obstruktionen. Tre väggar (10 cm betong, 20 cm betong och 1 mm stål) vardera med tre randvillkor (Exposed, Void och Insulated) utsattes för tre temperaturer (100 °C, 500 °C och 1000 °C) vilket ger 27 FDS simuleringar. Den adiabatiska yttemperaturen mättes i varje simulering och användes som indata till motsvarande FE-beräkningar. Resultatet påvisade inga signifikanta motsägelser vad gäller randvillkoren, med tillräcklig tid för termisk penetrering påverkade de den resulterande temperaturen som väntat. Undantaget var en mindre avvikelse i stålväggarna som utsattes för 100 °C och 500 °C med randvillkoren Exposed och Void där FDS aningen underskattade temperaturen relativt FE-beräkningarna. Gastemperaturerna i gridcellerna närmast väggen visade sig vara opålitliga. De tenderade att genomgå substantiella fluktuationer, troligen som ett resultat av hur FDS hanterar diskretiseringen av icke-solida volymer för Navier-Stokes beräkningarna. Dessa fluktuationer påverkade dock inte de resulterande solida temperaturerna eftersom medelgastemperaturen var korrekt. FDS påvisades även ha en tendens att aningen överskatta yttemperaturen under de första minuterna av simuleringarna relativt FE-beräkningarna. Temperaturerna från de två beräkningsmetoderna konvergerade dock efter några få minuter i samtliga tester. Dessa avvikelser ansågs ha för liten påverkan på de solida temperaturerna för att påvisa onoggrannhet i FDS. Därmed drogs slutsatsen att FDS:s beräkningar av temperaturer i solida material är tillräckligt noggranna inom dessa avgränsningar. / FDS (Fire Dynamics Simulator) uses a version of the Navier-Stokes equations to make accurate calculations of heat and gas flow through enclosures exposed to fire. The developers of FDS have, and continue to, validate it as new features get added in an attempt to increase its accuracy and broaden its potential applications. However, little of this effort is focused on FDS’ conductive heat transfer model, based on the one-dimensional Crank-Nicolson method. Thus, this study aims to test the accuracy of FDS’ conduction model by comparing it to calculations using FEM (Finite Element Method). FDS simulations were created so as to facilitate the study of a wall and its boundary conditions with as little interference from other factors as possible. This to create a controlled environment which easily could be replicated in the subsequent FE-calculations of the conductive heat flow through the solid obstructions. Three different walls (10 cm concrete, 20 cm concrete and 1 mm steel), each with the three different boundary conditions for the rear surface (Exposed, Void and Insulated), were exposed to three different temperatures (100 °C, 500 °C and 1000 °C) for a total of 27 FDS simulations. The adiabatic surface temperature was measured in each simulation in FDS and used as input for the corresponding FE-calculations. The results showed no clear inconsistencies in the boundary conditions, given enough time for thermal penetration they affected the resulting temperatures as expected. Save a slight deviation in the steel walls exposed to 100 °C and 500 °C with boundary conditions Exposed and Void where FDS slightly underestimated the temperature relative to the FE-calculations. The gas temperatures in the grid cells closest to the wall were found to be unreliable as they tended to undergo substantial fluctuations, likely as a result of how FDS handles the discretization of non-solid space for the Navier-Stokes calculations. These fluctuations were however not found to affect the solid temperatures as the mean gas temperature was accurate. FDS was also found to have a tendency to slightly overestimate the surface temperature in the first few minutes of the simulations relative to the FE-calculations. Though the resulting temperatures from the two methods converged after a few minutes at most in all tests. These deviations were considered to have too minor an impact on the solid temperature to justify claims of inaccuracy in FDS. Thus, the general conclusion of this study is that FDS’ predictions of solid phase temperatures are sufficiently accurate within these delimitations.

Roof venting is often utilised in large warehouses to remove smoke in order to reduce damage to a building and its contents, and to maintain access for fire-fighters. In New Zealand, the Compliance Document for the New Zealand Building Code C clauses recommends 15 % opening area for unsprinklered single floor buildings. This opening area is required to be designed for effective fire venting. There is no justification for why 15 % is required, and no definition of how fire venting qualifies as being effective. Fire Dynamics Simulator (FDS) was used to simulate the performance of various roof venting strategies in two different-sized industrial warehouses (both larger than 1,500 m²) with a 50 MW fire with both a rapid and an extreme t³ growth rate. In particular, roof venting areas of 15 %, 10 %, and 5 % of the floor area were tested with each of the following inlet areas for make-up air: 100 %, 50 %, and 0 % of roof venting area. In each of these cases, the vents were treated as permanently-open holes in the roof. It was shown that roof venting with 15 % geometric area is ample to provide and maintain tenability for fire-fighters. With sufficient inlet area for make-up air, smaller venting areas could also be employed. Further simulations were run to test the effect of square-shaped vents that opened simultaneously at 100°C compared with square-shaped vents that opened sequentially at 100°C, 200°C, and 300°C, and strip-shaped vents that opened progressively as each portion of a vent reached activation temperatures of 200°C and 300°C. Vents that opened at 100°C were intended to represent mechanical vents, while vents opening at higher temperatures were intended to represent plastic sky-light or drop-out type vents. The activation temperature proved to be more influential than the opening sequence or shape: there was a significant advantage to be gained by having vents that activated at 100°C as opposed to 200°C or 300°C. The role of downstands in aiding the effectiveness of roof venting was also investigated, with downstand depths of 10 %, 20 %, and 30 % of the ceiling height being simulated. Downstands were shown to be incredibly useful for exhausting smoke and hot gases, provided their installation was appropriately coordinated with placement of roof venting. It is concluded that a clear definition of effective fire venting must not only include the area of roof venting, but equally important is the definition of required inlet area for make-up air, as it plays a crucial role in the effectiveness of the specified roof venting area. In addition, the clear aerodynamic area should be specified. This could be achieved by use of a discharge coefficient that describes the proportion of the roof venting area that is clear aerodynamic area for a particular material, vent, and geometric area. Development of a clear definition of effective fire venting will help to determine how an economic fire protection system can be continued to be used, while going a long way to ensuring predictable and tenable conditions for fire-fighters in New Zealand.

In the rapidly growing field of CFD-calculations (Computational Fluid Dynamics), companies and organizations are bringing forth new tools, tools that display an image of a given fire scenario. These tools are developed because they provide time efficiency as well as a sustainable economic approach. Another useful tool is analytical solutions, these analytical solutions serve the same purpose as CFD-modeling, providing results of a given scenario. The purpose of this thesis was to simulate a fire plume with two different CFDprograms and compare the gas temperature from each simulation with a full-scale test. Also, analytical solutions were used to perform the same comparisons. Four different calculation models were utilized to obtain results. The CFD-programs were FDS (Fire Dynamics Simulator) and FireFOAM. The analytical solutions were performed using McCaffrey´s plume equation and Eurocode solutions for localized fire temperatures. FDS is a very well documented program, due to this, problems that arose were easily fixed. The structure of FDS enables the user to maneuver the program easily. SmokeView was used to visualize the simulation. FireFOAM is written in C++ and is operated through the command prompt. The structure of the program was time-consuming to understand mainly because of two reasons, primarily because the authors lack of knowledge in coding in C++, and second because of the LINUX environment. Moreover, the process of working in FireFOAM was mostly through trial and error. On some occasions, issues arose that could be solved by communication with other CFD users at CFD-Online. When major problems occurred, regarding the code or other CFD issues, Johan Anderson at RISE Research Institutes of Sweden guided us through most of these problems and enabled us to move forward with the work. ParaView was used to visualize the simulation, and Excel was used to evaluate the temperature data from the FDS- and FireFOAM simulations. For the calculations in FDS and FireFOAM, a sensitivity analysis was performed to see which grid size presented best results in each program. A grid size of 5 cm, 10 cm, and 20 cm were applied in FDS, and in FireFOAM the grid dimensions were set to 5 cm and 10 cm. The results showed that 5 cm was the most appropriate grid size for both programs. It would have been more favorably to simulate with several different grid sizes, to further strengthen the grid analysis. Though, due to the time frame of the thesis, further simulations were not performed. Calculations were repeated for the same scenario only with a lower HRR (Heat release rate). An extensive sensitivity analysis was conducted for FDS in the form of two different simulations. One simulation where HRR was the same as the full-scale test but with twice the area of the burner. In the second simulation, the same area was used on the burner as the fullscale test, but with half the HRR. Results from the analytical solutions were easy to achieve; however, the model has some limitations regarding calculations within the flame region. The estimated gas temperature, using FDS, aligns well with the full-scale test. The temperatures analyzed from FireFOAM deviated in general through the flame region and reached unreasonable high temperatures close to the ceiling. Since the analytical solutions were based on different conditions compared to those applied in the full-scale test, it was expected that the results should deviate. However, McCaffrey plume equations can still be used to give an approximate picture of scenarios similar to that of the full-scale test, and the same applies to Eurocode solutions for localized fire temperatures. Analysis of the results shows that FDS can be used to simulate similar scenarios. FireFOAM simulates a gas temperature that is overestimated within the flame region. One of the reasons for this was due to the grid size since the sensitivity analysis III showed that a refined grid size resulted in more correct temperature value, the reason for not simulating with a more refined grid size was due to the restricted time frame of this thesis. FireFOAM is, at present, recommended for researchers who wish to use the code for specific purposes. Therefore, given the same premises, FireFOAM is not recommended for the standard fire safety analysis.

Este trabalho tem como objetivo implementar e testar modelos de gás cinza atualizados na rotina de radiação térmica do software Fire Dynamics Simulator (FDS), além da utilização do próprio modelo de gás cinza disponível no software, para a predição do fluxo de calor radiativo. Os modelos de gás cinza estudados foram o modelo padrão do software FDS (aqui denominado como GC1), e os modelos de gás cinza mais atuais: o GC2, no qual o coeficiente de absorção do meio participante é dado por relações polinomiais, e o GC3, sendo este um modelo de gás cinza que baseia o cálculo do coeficiente de absorção no modelo WSGG. Os novos modelos de gás cinza foram implementados no código fonte do software FDS, o qual é um código aberto, e a verificação da implementação foi realizada através da solução numérica do equacionamento utilizando os valores reportados pelo software. Com os novos modelos de gás cinza já corretamente implementados, passou-se então para a simulação computacional dos casos previamente selecionados. Para todos os modelos de gás cinza, foram simulados incêndios em poças, para diferentes combustíveis (etanol, n-heptano e metanol) em diferentes cenários de incêndio, considerando ou não a presença de fuligem no sistema. Os cenários de incêndio eram: (i) totalmente fechado, (ii) totalmente aberto e (iii) com uma condição intermediária, fechado, porém com uma abertura para o meio externo. Um estudo de análise de malha e de diferentes parâmetros, como o estudo da quantidade necessária de ângulos sólidos discretos, foram realizados para correta padronização dos parâmetros. As simulações computacionais foram validadas para o modelo de gás cinza padrão do FDS através da comparação de resultados com aqueles reportados na literatura específica de cada caso. Com os modelos já validados simulou-se novamente cada cenário de incêndio com os diferentes modelos de gás cinza anteriormente implementados. A partir da análise dos resultados obtiveram-se boas concordâncias para os campos de temperatura, frações molares tanto de CO2 quanto de H2O e para as frações volumétricas de fuligem. Os fluxos de calor radiativos foram corretamente preditos para todos os modelos de gás cinza implementados. O modelo GC2 apresentou resultados com desvios médios na faixa de 15%, o modelo de gás cinza baseado no WSGG (GC3) apresentou os melhores resultados, com erros médios inferiores a 10%, enquanto que o modelo padrão do software, GC1, apresentou resultados intermediários. / This work aims to implement and test updated gray gas models in the thermal radiation routine of the Fire Dynamics Simulator (FDS) software, as well as the use of the gray gas model available in the software to the prediction of radiative heat flux. The gray gas models studied were the default model of the FDS software (determined GC1), and the most current gray gas models: the GC2, in which the absorption coefficient of the participant medium is given by a polynomial relations, and the GC3, which is a gray gas model that was based on the calculation of the absorption coefficient in the WSGG model. The most recently gray gas models were implemented in the source code, which is an open source, and the verification of the implementation was performed by the numerical solution of the equations from the reported values of the software. With the new gray gas models already implemented, the next step was the computational simulation of the previously selected cases. For all the gray gas models, pool fires were simulated different scenarios of fire for different fuels (ethanol, nheptane and methanol), with and without considering soot presence in the system. The fire scenarios were: (i) fully closed, (ii) fully open and (iii) with an intermediate condition, closed but with an opening to the external environment. A study of a mesh analysis and different parameters, such as the study of the required amount of discrete solid angles, were performed to correct the standard parameters. The computational simulations were verified for the default gray gas model of the FDS by comparing the simulations results with those reported in the specific literature of each case. With the models already verified, each fire scenario was simulated with the different gray gas models previously implemented. From the analysis of the results, good agreements were obtained for the fields of temperature, molar fraction of CO2 and H2O and soot volume fraction. The radiative heat fluxes were correctly predicted for all gray gas models early implemented. The GC2 model present results with average deviation in the range of 15%, the gray gas model based on WSGG (GC3) presented the best results, with average deviation lower than 10%, while the default software model (GC1) presented intermediate results.

Devant le besoin de nouveaux outils d'aide à l'investigation post-incendie, cette thèse se propose d'évaluer le recours à des modèles numériques pour apprécier un scénario proposé par un expert. Pour cela, les conditions d'utilisation de la version 4 de Fire Dynamics Simulator (FDS) ont été déterminées dans une optique de reconstitution de sinistres. Une méthode a ensuite été développée afin de confronter les résultats des simulations aux observations faites lors de l'investigation : cette méthode se base sur l'utilisation de multiples points de comparaison qui sont des effets thermiques ou mécaniques remarquables sur un matériau. Les résultats obtenus ont ensuite été utilisés pour la simulation de deux cas réels. Le premier s'attache à comparer, à des simulations, des mesures de propagation de flammes à la surface d'un matelas dans deux configurations différentes. Cela est réalisé afin d'évaluer le modèle de combustion solide de FDS dans différentes conditions de ventilation. La seconde application est la reconstitution d'un incendie ayant fait une victime dans un appartement. Ce second cas a été choisi dans le but d'évaluer les méthodes de simulation et d'utilisation des points de comparaison établies dans les premiers chapitres.

This thesis examines the prediction of opposed flow flame spread in the Fire Dynamics Simulator version 4 (FDS4) Computational Fluid Dynamics (CFD) model by adapting the Lateral Ignition Flame Transport (LIFT) test procedure. It should be noted that FDS4 was all that was available at the time of the analysis despite FDS5 is now available for beta testing. This research follows on from previous work where LIFT experiments were conducted for various New Zealand timber and timber based products; those materials include Beech, Macrocarpa, Radiata Pine, Rimu, Hardboard, Medium Density Fibreboard (MDF), Melteca faced MDF, Plywood and Particle Board. The objective of this research is to investigate the accuracy of flame spread modelling in FDS4; where the prediction of opposed flow flame spread parameters from FDS4 were directly compared with the experimental results that were obtained experimentally. The standardised procedure for determining the material ignition and flame spread properties was followed and applied to simulate the LIFT test. The LIFT test apparatus was set up in FDS4 with a domain size of 0.9 x 0.3 x 0.3 metres in the x, y and z directions respectively. From the heat flux distribution along the calibration specimen, it indicated that calibration of the LIFT apparatus can be executed in FDS4 where the percentage error is within 1.2%. This report also provides the thermal transport properties (i.e. thermal conductivity and specific heat capacity) of the tested New Zealand timber and timber based products. These were determined using a transient plane source technique and subsequently these properties were entered as the surface identifications in FDS4. The ignition tests were not performed as part of the simulated LIFT test since a direct comparison with the results was required to give a more meaningful assessment. For this reason, the ignition parameters that were obtained from the previous experiments were employed to carry out the flame spread test. Due to the concept of a preheat time required by the standard test method and FDS4 being not able to preheat specimens, the temperature immediately after the preheat time was calculated and implemented for the specimens. The heat transfer problem was solved using an explicit method; where specimens were divided into 11 different nodes. Different scenarios were investigated to see the effect that the selected combustion model has on modelling flame spread. The two analytical models tested were (1) thermoplastic fuels and (2) charring fuels model. Furthermore, the flame spread was visualised using either the Mixture Fraction or the HRRPUV model in Smokeview; where the rate of flame spread for each specimen was obtained. And lastly, three different absorption coefficients (0.6, 0.7 and 0.8) for each specimen were examined; this parameter contributed significantly to the rate of flame spread as it determines the amount of heat flux being absorbed by the specimen during the time of preheating. A study of the grid size was also performed to investigate the accuracy of the FDS4 simulations with the grid size selected. It has been found that increasing the size of the grid cell does not greatly affect the flame spread results. Moisture content and heat of vaporisation input variables were also examined. From the flame spread data, moisture content does not have a significant role in modelling flame spread. However, it was indicated that the heat of vaporisation has an effect on the output of the flame spread parameters. It was determined from the sensitivity analysis that the most appropriate solid boundary condition to be used in predicting the flame spread would be thermoplastic fuels model with an absorption coefficient of 0.8. By using this scenario as the basis, the plot of the arrival time against the distance along the specimen exhibits a similar trend of flame spread with the experimental results at first, but later on, the extinction of flame front actually occurred at a much earlier stage than the experimental results showed. In general, the analyses showed that FDS4 cannot perform the LIFT test where the prediction of flame heating parameter and minimum heat flux for spread were out by more than 20% shown by the direct comparison between experimental results. However, the prediction of minimum heat flux required for ignition seems to agree with the experimental results where the percentage error is within 20%.

Malaria är en farlig tropiksjukdom orsakad av parasiten Plasmodium som vållar många dödsfall varje år. Sedan några år tillbaka rekommenderar Världshälsoorganisationen (WHO) användandet av artemisinin och dess derivat för behandlandet av malaria. Artemisinin syntetiseras normalt i växten Artemisia annua i lågt utbyte. På grund av det låga utbytet är läkemedlet väldigt dyrt. Då parasiten blivit resistent mot de flesta malarialäkemedel är artemisinin ett viktigt preparat i kampen mot malaria. Forskning pågår för att hitta nya eller effektivare metoder för framställning av substansen då en oro finns att produktionen från A. annua inte kommer kunna möta kraven från läkemedelsindustrin. En av teorierna är ifall andra växter inom Artemisia-släktet kan syntetisera artemisinin då flera växter uppvisat helande effekter vid andra sjukdomar. I denna studie undersöktes det ifall växterna A. vulgaris och A. absinthium från Artemisia-släktet skulle kunna syntetisera artemisinin. Med hjälp av molekylärbiologiska tekniker isolerades genetiskt material ifrån växterna. Materialet granskades efter ribonukleinsyra (RNA)- och deoxiribonukleinsyra (DNA) -sekvenser för funktionella enzym som katalyserar reaktioner i artemisinins biosyntes. Ifall generna uttrycks för dessa enzym kan eventuellt artemisinin bildas. Växterna hämtades från Revsudden, Sverige och genetiskt material isolerades. Förekomsten av genuttryck för fem viktiga enzym i artemisinins biosyntes undersöktes med Polymerase Chain Reaction (PCR). Resultatet blev att växterna hade genuttryck för två respektive tre av de fem enzymen. Detta pekar mot att varken A. vulgaris eller A. absinthium kan syntetisera artemisinin då de saknade några viktiga nyckelenzym i syntesen. Trots att en tidigare studie indikerar närvaro av artemisinin i dessa växter kan slutsatsen dras att A. vulgaris och A. absinthium inte kan bilda artemisinin. / Malaria is a tropical disease that accounts for the death of many people annually and is caused by a parasite called Plasmodium. The World Health Organization (WHO) recommends artemisinin and its derivates for malaria treatment. Artemisinin is synthesized generally in Artemisia annua in small amounts. The artemisinin-treatment is very expensive due to the small amounts produced in the plant. Since the parasite has developed resistance towards many antimalarial drugs, artemisinin is an important drug against malaria. Research to find alternative methods for artemisinin-production has begun because there is a great concern that artemisinin-production at current rate will not meet the demand from the pharmaceutical industry. Some speculate if artemisinin can be synthesized in other plants from the Artemisia-genus since many plants have shown healing properties towards other diseases. In this study, we investigated if A. vulgaris and A. absinthium could produce artemisinin. Using molecular biology techniques, genetic material was isolated from the plants. Ribonucleotide (RNA)- and deoxyribonucleotide (DNA)- sequences which encode important enzymes in the artemisinin biosynthesis were examined. In case all the genes were expressed, artemisinin may be synthesized. The plants were picked on Revsudden, Sweden and genetic material was isolated. The presence of gene expression of five important enzymes in the artemisinin biosynthesis was investigated by Polymerase Chain Reaction (PCR). The results showed that the plants had gene expression of two respectively three of the five enzymes. Due to the fact that the plants need all five enzymes to synthesize artemisinin, even though a recent study has shown presence of artemisinin in these plants, this study concludes that artemisinin cannot be synthesized in A. vulgaris and A. absinthium.

El presente documento, se enmarca en el proyecto FONDECYT No1085015 y corresponde a un estudio numérico que propone a las cortinas de aire de Doble Jet-Doble Flujo (DJ-DF) planas y verticales, como elementos que provoquen el confinamiento celular de la mayor parte del calor producido por una fuente calórica al interior de un túnel. La modelación se realizó en base a la instalación experimental completa del Laboratorio de Estudios en Fluidodinámica (LEF), del Departamento de Ingeniería Mecánica de la Universidad de Chile, que contiene una fuente térmica localizada de calor y dos cortinas de DJ-DF entre las cuales se busca confinar el calor. Las simulaciones numéricas fueron realizadas en base a un modelo computacional de fluidodinámica (CFD) en código Fire Dynamics Simulator (FDS), con tratamiento de la turbulencia mediante Large Eddy Simulation (LES), en el Centro de Modelación Matemática (CMM) de la Universidad de Chile, específicamente en el Cluster Levque, el cual permitió que dichas simulaciones se llevaran a cabo en procesadores múltiples. Con la finalidad de validar el modelo numérico, los casos simulados se definieron en base a los estudiados experimentalmente por Cecchi [7], variando la velocidad de cada uno de los jets que componen el DJ-DF y la potencia de la fuente calórica; más aún se compararon los perfiles obtenidos experimentalmente y numéricamente, de velocidad y temperatura en torno al DJ-DF más cercano a la fuente térmica (en distintos niveles horizontales), obteniendo resultados satisfactorios en términos de orden de magnitud y forma de los perfiles para dos de los tres casos de estudio. En relación a las características confinatorias del DJ-DF, se construyeron en torno al mismo: los campos de velocidad y temperatura, además de los perfiles de intensidad de turbulencia térmica y de transporte turbulento de cantidad de movimiento y calor. Para los tres casos de estudio se concluye que el confinamiento es efectivo exceptuando la zona de impacto, en donde se identificaron fugas de calor y masa mediante mecanismos turbulentos. También se estudié la formación de estructuras rotacionales en las capas de mezcla del lado frío y caliente y su relación (o implicancia) en la capacidad confinatoria del DJ-DF. En base a lo anterior, se concluye que el confinamiento de calor de la cortina es más efectivo en el caso de la configuración DJ-DF con el jet rápido correspondiente al lado frío o de aire fresco. Para un trabajo futuro, se sugiere continuar con el estudio del fenómeno incluyendo la combustión real, para así determinar la concentración de humo o productos de la combustión, como otra característica indicativa del confinamiento de calor por parte de la cortina.

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