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Novel methods of characterizing phthalate emissions and their fate and transport in residential indoor environmentsLiang, Yirui 15 January 2015 (has links)
Phthalates have been used pervasively as plasticizers in consumer products and building materials. These semi-volatile organic compounds (SVOCs) are ubiquitous in indoor environments, redistributing from their original sources to indoor air, and subsequently to all interior surfaces. Because they partition strongly to surfaces, most phthalates persist for years after the source is removed. Biomonitoring data based on blood and urine testing provide direct evidence of the universal and significant human exposure to phthalates, which may result in serious adverse health effects. However, effective strategies to limit exposures to phthalates remain hamstrung by our poor understanding of their sources and fate and transport in indoor environments. The goal of this research is to explicitly elucidate the fundamental mechanisms governing emission, transport, and human exposure associated with phthalates in indoor environments. The specific research objectives are to 1) develop a novel, rapid, small-chamber method to determine the key parameters that control phthalate emissions and characterize the emissions; 2) investigate the influences of temperature, air flow rate, and surface sorption on phthalate emissions via a series of controlled tests in small and large chambers; 3) develop and validate a new indoor fate and transport model for phthalates with consideration of particle dynamics and its effects on emission and sorption. This research, which connects emission measurements to chemical transport and exposure assessment, will explicitly elucidate the fundamental mechanisms governing emission, transport, and human exposure associated with phthalates in indoor environments. / text
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Experimental study of single sided ventilation through a multi-configuration slotted louvre systemO'Sullivan, Paul D. January 2018 (has links)
Evidence based performance of novel ventilation systems in existing low energy buildings is invaluable as it provides data on the system operation in a real dynamic environment. This thesis presents the outcomes from research involving a number of experimental field studies of a single sided ventilation system installed in a single cell office space as part of a building retrofit pilot project in Cork, Ireland. The solution consists of a purpose provided, multi configuration opening, comprising a narrow slotted architectural louvre component split across a low level manual opening section and a high level automated opening section. A review of published research found that little experimental data exists on the performance of such systems and air flow rate correlations developed for plain openings are currently used by designers to make predictions about their performance. Three experimental campaigns were designed and carried out. First, in order to quantify performance of the system, long term and short term monitoring of the internal thermal and air flow environment at the experimental building was completed. Second, ventilation rate measurements in existing and retrofit spaces were completed using a tracer gas concentration decay technique. Thirdly, air flow through the single sided slot louvre opening was investigated. In addition, the annual cooling potential of the multi-configuration system was investigated computationally. Results show there was a significant difference between both thermal environments with the retrofit space consistently displaying lower air temperatures over the cooling season and throughout all Air Change Rate measurement periods. Lower levels of vertical thermal stratification and diurnal temperature variation were also observed. On average, across a wide range of boundary conditions, lower ventilation rates were observed for the slotted louvre system with a narrower spread of values when compared with the existing building. The dominant driving force was either buoyancy or wind depending on the opening configuration adopted in the slotted louvre system. The slot louvre was found to be wind dominant for lower opening heights when compared with a plain opening of the same dimensions. Existing single sided correlations were found to perform better when predicting airflow rates through a plain opening when compared with the slot louvre system and a new dimensionless exchange rate parameter is proposed for predicting wind driven airflow through the slot louvre. Simulations indicate that 80% of annual occupied hours required an enhanced ventilative cooling airflow rate to achieve internal thermal comfort. Using a combination of configurations the system was able to provide the required cooling airflow rate for 93% of the occupied hours.
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Ventilation i Fältsjukhus under en pandemiKabawi, Marial, Chamoun, Gabro January 2021 (has links)
As a measure to deal with Covid-19, the Swedish Armed Forces built field hospitals inStockholm and Gothenburg, in order to accommodate several patients, as the Stockholm regionand the Västra Götaland region feared that the pandemic would overload the intensive care unitin particular. Field hospitals were criticized for poor coverage and dimensioning of the variouscare facilities as well as poor ventilation.The aim of the study is to limit the spread of infection in the intensive care unit at field hospitalsand hospitals. The ventilation systems are studied and investigated the possibility ofsupplementing the system with cost-effective equipment, such as air purifiers. The two questionsare how do the number of air turnovers per hour affect the air quality in the room and how is theparticle concentration in a care room affected by the placement of independent air purification.The study is based on several particle measurements and a smoke test.Particle measurements were performed sequentially, to create a level playing field before eachmeasurement. In addition, three different placements were presented on standalone airpurification and a smoke test was performed to visualize the movement of the air. The resultsshow that with the help of the air purifier, particle reduction can increase to 50% already at 5air turnovers per hour (ACH). The most effective air turnover is considered to be ACH, as thisreduces the particle content of a room with a patient to as low levels as if ther was not a patientin the room.
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Vliv volby vstupních parametrů zařízení Blowerdoor testu na výslednou hodnotu průvzdušnosti / Influence of choice of input parameters blowerdoor test equipment on the final value of air permeabilityKermes, Adam January 2013 (has links)
The thesis examines the influence of choice of input parameters Blowerdoor test equipment on the final value of air permeability. Measurements have been performed on a set of four experimental buildings and one room.
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Chaleur – Humidité – Air dans les maisons à ossature bois : Expérimentation et modélisation / Heat, Air and Moisture coupled transfers in wooden frame houses : Experimental investigations and numerical modellingLabat, Matthieu 21 November 2012 (has links)
L’évolution actuelle des exigences en termes de performance énergétique des bâtiments a fait apparaître de nouveaux enjeux et problématiques scientifiques, dont ceux liés à l’humidité. Cette étude s’appuie sur une cellule expérimentale construite sur la technologie des maisons à ossature bois et soumise aux conditions climatiques réelles de Grenoble. L’instrumentation de ce bâtiment et le suivi de l’évolution en température et en humidité dans les différentes couches de l’enveloppe permettent de définir des séquences nécessaires à la validation de modèles numériques. Dans cet objectif, un modèle existant nommé HAM-Tools a été utilisé pour simuler les transferts couplés de chaleur, d’air et d’humidité à l’échelle du bâtiment. La démarche de validation a été décomposée en plusieurs étapes, de manière à cibler des transferts spécifiques et d’en améliorer la modélisation. Ces études localisées concernent les transferts couplés de chaleur et de masse à travers les parois solides, la modélisation des transferts de chaleur à travers une lame d’air ventilée et enfin la modélisation du renouvellement de l’air intérieur en conditions naturelles. Pour estimer la précision globale du modèle, c'est-à-dire à l’échelle du bâtiment, une séquence expérimentale a été simulée en prenant en compte l’ensemble des transferts couplés simultanément. Les performances du modèle sont discutées à partir des mesures locales, c'est-à-dire dans les parois, puis globales. La bonne concordance entre mesures et résultats de simulation permet de conclure sur la validité et la généricité de la démarche mise en œuvre et les hypothèses de simulation. Plus particulièrement, il est apparu que l’outil de modélisation permet de prédire correctement le comportement moyen des parois en humidité et en température. Il est donc envisageable de l’utiliser pour simuler et estimer l’impact des constituants des parois en termes de durabilité, de performances énergétiques et de confort de l’occupant. / As energy saving is so important in buildings nowadays, envelopes performances have to be more efficient and have to deal with more obligations, such as moisture accumulation and mould growth. This study relies on an experimental wooden frame house exposed to the natural conditions of Grenoble, France. It has been widely instrumented so the wall’s temperature and humidity is monitored at different depths. As a consequence, complete dataset are available and can be used to validate numerical model. In this work, an existing numerical model named HAM-Tolls has been used to simulate the heat, air and moisture coupled transfers at the building scale. The method developed here consists in validating the numerical model step by step, with studying specific transfers separately. The first step deals with heat and mass transfers across the walls. Then, the heat transfers across a ventilated air gap and the air change rate under natural conditions have been studied much in detail. The final step of this works consists in simulating simultaneously every transfer at the building scale. This latest simulation’s results were compared both on a local and on a global point of view with the measurements. As they were found to be in good agreement, this allows concluding on the methodology efficiency, the validity of the modelling assumption and gives good hope with extending this methodology to other studies. Specifically, the simulation tool is able to predict correctly the average temperature and humidity content within the walls. Therefore, it should be suitable with estimating the wall components influence on the wall durability, its energy efficiency and its impact on the occupant’s thermal comfort.
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