A mathematical model describing the transport and distribution of fluid and plasma proteins between the circulation, the interstitium, and the lymphatics, is formulated for the human. The formulation parallels that adopted by Bert et al.[5] in their model of microvascular exchange in the rat. The human microvascular exchange system is subdivided into two distinct compartments: the circulation and the interstitium. Both compartments are treated as homogeneous and well-mixed. Two alternative descriptions of transcapillary exchange are investigated: a homoporous "Starling Model" and a heteroporous "Plasma Leak Model". Parameters which characterize fluid and protein transport within the two models are determined by a comparison (quantified statistically) of the model predictions with selected experimental data. These data consist of interstitial fluid volumes and colloid osmotic pressures measured as a function of plasma colloid osmotic pressure for subjects suffering from hypoproteinemia. The relationship between this fitting data and the model transport parameters is investigated using a visual "graphical optimization technique" and additionally, in the case of the Starling Model, by use of a non-linear optimization technique. Both the Starling Model and the Plasma Leak Model provide good representations of the fitting data for several alternative sets of parameter values. The ranges of parameter values obtained generally agree well with those available in literature. The fully determined model is used to simulate the transient behaviour of the system when subjected to an intravenous infusion of albumin. All alternative "best-fit" parameter sets determined for both models produce simulations which compare reasonably well with the experimental infusion data of Koomans et al.[42]. The predictions of both models compare favourably not only with the available experimental data but also with the known behavioural characteristics of the human microvascular exchange system. However, no conclusions may be drawn regarding which of the alternative transcapillary transport mechanisms investigated provides the better description of human microvascular exchange, although it appears likely that diffusion of proteins plays a significant role in both. Final model selection and choice of fitting parameters await the availability of more and better microvascular exchange data for humans. Analysis of both the Starling Model and Plasma Leak Model indicates that the microvascular system is capable of regulating the interstitial fluid volume over a fairly wide range of transport parameter values. The important model-predicted passive regulatory mechanisms are tissue "protein washout", which reduces its colloid osmotic pressure,and a low tissue compliance which increases the hydrostatic pressure of the interstitium as it becomes hydrated. It would therefore seem that the human microvascular system can be regarded as a fairly "robust" system when considering its ability to regulate interstitial fluid volume (i.e., small changes in the values of transport parameters, such as the capillary wall permeability, have little effect on the conditions and operation of the system). / Applied Science, Faculty of / Chemical and Biological Engineering, Department of / Graduate

Understanding the relevant behaviour of fire in buildings is critical for the continued provision of fire safety solutions as infrastructure continually evolves. Traditionally, new and improved understanding has helped define more accurate classifications and correspondingly, better prescriptive solutions. Among all the different concepts emerging from research into fire behaviour, the compartment fire is probably the one that has most influenced the evolution of the built environment. Initially, compartmentalization was exploited as a means of reducing the rate of fire spread in buildings. Through the observations acquired in fires, it was concluded that reducing spread rates enabled safe egress and a more effective intervention by the fire service. Thus, different forms of compartmentalization permeated through most prescriptive codes. Once fire behaviour within a compartment was conceptualized on the basis of scientific principles, the compartment fire framework became a means to establish, under certain specific circumstances, temperatures and thermal loads imposed by a fire to a building. This resulted not only in improved codes but also in a scientifically based methodology for establishing the thermal input from which to assess structural performance. The last decades have however seen an evolution of the built environment away from compartmentalization while the classic compartment fire framework has remained. Within this framework, while Regime I corresponds to the idealised experimental setups adopted by many of the researchers, the usually ignored Regime II is characteristic of open spaces and volumes, typical of contemporary architecture. This research project commences, through a review of classic literature by those regarded as the fathers of fire safety engineering, by revisiting the knowledge underpinning this seminal approach, and initiating the discussion of its continued relevance and applicability to an increasingly non-compartmentalised built environment. Compartment fires are extremely complex processes. Nevertheless, when treating the theoretical problem with sufficient accuracy, simple mathematical approaches can be extremely informative and serve as the background to more complex methodologies. In this context, the project introduces the problem of the compartment fire in its full complexity before discussing some simplifications typically assumed when representing the actual problem for design purposes. Further, despite the detailed experimental and theoretical background behind analytical formulations in the classic compartment fire framework, their development is revisited to establish the extent to which they can be applied. In this way, the range of validity of the classic framework is characterized, clarifying the limitations of existing design methods based on this framework, and identifying the areas where further research and extension is necessary. Given the importance of counting on simple analytical formulations at the early design stage when dealing with atypical architectural designs in today’s fire safety practice, an elementary theoretical compartment fire framework is elaborated with the aim of enveloping traditional as well as contemporary architectural layouts. This gave way to the development of a new set of regime of behaviour definitions, in addition to – and falling in-between – the classic Regime I and Regime II fullydeveloped compartment fire behaviours. With the aim of filling this gap of knowledge empirically and characterizing these additional behaviours, a series of small and large-scale tests are presented. The results demonstrate complex behaviours that cannot be described in terms of the classic framework. This evidences the great need to conduct research that provides physical insight into the dynamics of a fire in spaces that deviate from the small quasi-cubic enclosure – the natural consequence of compartmentalization – that was typically adopted throughout the original work that resulted in the data which validated the classic compartment fire framework. Overall, this project aims to inform and encourage the discussion of the existence of a broader compartment fire framework, where the historical Regimes I and II are limiting cases of a vaster fire behaviour which is intimately linked to the geometry of the compartment, the ventilation conditions, and the available fuel. While the classic compartment fire framework is still a robust tool, it is only one piece in the puzzle of approaching and resolving the fire problem in a building in a holistic way. The relevance of this discussion is apparent in face of contemporary architecture and infrastructure.

Pour des raisons d'économie d'énergie, les façades des bâtiments deviennent de plus en plus sophistiquées à la fois par leurs configurations et leurs compositions. Mais la quantité de combustible de ces nouvelles façades est bien supérieure à celle des façades traditionnelles. Par conséquent, le risque de propagation du feu via la façade est plus important. Ainsi, l'objectif de ce travail est de modéliser le développement du feu à l'intérieur et à l'extérieur d'un bâtiment en prenant en compte différentes configurations et compositions de façade. Cette recherche expérimentale et numérique a permis d'identifier les paramètres qui augmentent ou diminuent le risque de propagation du feu via une façade. Dans un premier temps, après avoir vérifié la capacité du code de calcul à modéliser les flammes pariétales, une étude numérique qui étudie l’influence de la géométrie d’une façade sur la propagation du feu via la façade a été réalisée. En effet, les différents phénomènes liés aux dimensions des ouvertures et/ou à la configuration de la façade ont été identifiés. Il a donc été possible d’analyser leur influence sur le risque de propagation du feu en façade à travers des grandeurs telles que la puissance libérée à l’extérieur du bâtiment ou encore la hauteur de flamme et les actions thermiques engendrées. Parmi les configurations étudiées figurent des géométries plus ou moins complexes pouvant être rencontrées sur les bâtiments. Par exemple, les ouvertures multiples ou encore des configurations en « U » afin d’étudier l’influence de l’effet cheminée sur l’extension des flammes. En effet, ce type de configurations a déjà été la cause d’une propagation rapide d'incendies via des façades quelles que soient leurs compositions. Par la suite, une étude expérimentale sur la propagation du feu sur une paroi combustible a été réalisée avec deux objectifs. Tout d’abord afin d’étudier les phénomènes de propagation sur une façade combustible (température de flamme, hauteur de propagation, contribution énergétique de la façade), mais également pour récolter des données expérimentales permettant la validation de modèles de propagation et les simulations numériques dans cette situation. Dans un deuxième temps, une nouvelle campagne expérimentale a permis d’étudier l’influence de la présence d’une lame d’air de ventilation entre le bardage et le mur sur la propagation du feu. Cette dernière configuration est largement utilisée dans la construction des façades comportant généralement une couche d’isolation dans la lame d’air. Cette recherche, à la fois académique et applicative, a permis de fournir des informations originales sur le développement et le comportement du feu le long d’une façade, qu’elle soit combustible ou non. Les résultats numériques présentés mettent en évidence les différents paramètres gouvernant le développement d’un feu le long d’une façade, ce qui facilite la compréhension des phénomènes liés à cette problématique. De plus, les différents essais réalisés pourront servir de base de données à la modélisation de la propagation d’un incendie le long d’une paroi combustible, ainsi qu’à la mise au point des modèles de développement et de propagation. / In order to enhance the energy efficiency of buildings, the facades are becoming more sophisticated in both their configurations and compositions. However, the amount of fuel of these new facades is much higher than that of traditional facades. Therefore, the risk of fire spread through the facade is more important. Thus, the objective of this work is to model the fire development inside and outside of a building, taking into account different configurations and facade compositions. This experimental and numerical research has identified the parameters that increase or decrease the risk of fire spread via the façade. First, after verifying the capacity of the FDS code to model the parietal flames, a numerical study that examines the influence of the geometry of a facade fire spread was completed. Indeed, the various phenomena related to openings dimensions and / or configurations of the façade have been identified. It was therefore possible to analyze their influence on the risk of fire spread along the façade using quantities such as the heat released outside the building, the flame height and thermal actions (temperature, fluxes). Among the configurations studied are contained more or less complex geometries that can be encountered on the buildings. For example, multiple openings or "U" configurations were investigated in order to study the influence of the chimney effect on the extension of flames. Indeed, this type of configuration has already been the cause of the rapid spread fire through walls regardless of their compositions. Subsequently, an experimental study on fire spread along a combustible wall was realized with two goals. First, a series of tests was performed in order to observe propagation phenomena on a combustible façade and to collect experimental data to validate propagation models and numerical simulations in this situation. Secondly, another experimental campaign was used to study the influence of the presence of a ventilation air gap between the cladding and the wall on the spread of fire. This latter is widely used in the construction of facades. This research, both academic and applicative, has provided new information on the fire development and fire behavior along a façade, combustible or not. The numerical results demonstrate the various parameters governing the development of a fire along a façade, which facilitates the understanding of phenomena related to this issue. In addition, various tests can be used as a database for the modeling of fire spread along a combustible wall. Thus, this work contributes to the development of models of fire development and spread on buildings via the façade.

This work is an experimental and theoretical analysis of factors and conditions affecting smoke and carbon monoxide (CO) production in corridor-like enclosure fires. Thirty eight experiments were performed in a three metre long corridor-like enclosure having a cross section 0.5 m x 0.5 m, door-like openings in the front panel and a propane gas burner located near the closed end. Measurements of smoke and carbon monoxide concentrations were performed at locations inside the enclosure and also in the exhaust duct of a hood collecting the combustion products. The main conclusion of this work is that smoke production depends not only on the fuel and Global Equivalence Ratio (GER) - as is reported in the literature - but also on the temperatures and residence time inside the enclosure, at least for the experimental conditions examined in this study. Additionally, it was found that the smoke concentration inside the enclosure was increasing during the ventilation controlled regime even after external burning started. Such increase was verified by temperature, smoke and velocity measurements inside the enclosure. The increase was due to reverse flow behind the flames travelling along the corridor. Namely, the gases reversed direction behind the flames with hot gases travelling in the upper layer backwards towards the closed end of the corridor in contrast to hot gas movements towards the opening in front of the flames. This recirculation was confirmed by velocity and oxygen concentration measurements in the upper and lower layers inside the enclosure. In addition, the present results show that the relationship reported in the literature between smoke and carbon monoxide production during overventilated conditions yco/ys ≈ constant, is no longer valid during an underventilated enclosure fire. The ratio yco/ys increases for the Global Equivalence Ratios of the enclosure greater than one. The obtained results are useful for CFD validation and specifically applicable for assessing smoke hazards in corridor fires in buildings where smoke concentrations can be much larger than anticipated owing to leakage to adjacent rooms behind travelling flames.

This work is an experimental and theoretical analysis of factors and conditions affecting smoke and carbon monoxide (CO) production in corridor-like enclosure fires. Thirty eight experiments were performed in a three metre long corridor-like enclosure having a cross section 0.5 m x 0.5 m, door-like openings in the front panel and a propane gas burner located near the closed end. Measurements of smoke and carbon monoxide concentrations were performed at locations inside the enclosure and also in the exhaust duct of a hood collecting the combustion products. The main conclusion of this work is that smoke production depends not only on the fuel and Global Equivalence Ratio (GER) - as is reported in the literature - but also on the temperatures and residence time inside the enclosure, at least for the experimental conditions examined in this study. Additionally, it was found that the smoke concentration inside the enclosure was increasing during the ventilation controlled regime even after external burning started. Such increase was verified by temperature, smoke and velocity measurements inside the enclosure. The increase was due to reverse flow behind the flames travelling along the corridor. Namely, the gases reversed direction behind the flames with hot gases travelling in the upper layer backwards towards the closed end of the corridor in contrast to hot gas movements towards the opening in front of the flames. This recirculation was confirmed by velocity and oxygen concentration measurements in the upper and lower layers inside the enclosure. In addition, the present results show that the relationship reported in the literature between smoke and carbon monoxide production during overventilated conditions yco/ys ≈ constant, is no longer valid during an underventilated enclosure fire. The ratio yco/ys increases for the Global Equivalence Ratios of the enclosure greater than one. The obtained results are useful for CFD validation and specifically applicable for assessing smoke hazards in corridor fires in buildings where smoke concentrations can be much larger than anticipated owing to leakage to adjacent rooms behind travelling flames.

Within the framework of this Final Year Project in Mechanical Engineering an investigation is done for a Suitable Bonding Method for a Multi-Material Glove Compartment for Lightweight Design. The industrial partner of this Project is Swedfoam. Decreasing fuel consumption and lowering the carbon foot print for automobiles, lightweight construction is one of the key factors to achieve these regulations and more crucial these aims as future needs. Often a simple idea already has a great potential, such as replacing conventional materials with lighter ones in certain applications. Exactly this is done for the lid of a glove compartment; a metal plate, used as a core of the application beforehand is disposed and replaced with a composite, which decreases the weight of the lid significantly. A problem is faced with the new design of the inner lid of a glove compartment, because due to the lighter material the joining method is changed to bonding. Previously the bonding failed mainly due to temperature changes. A literature survey on the material data is done, as well as lab experiments on the used composite in order to characterize crucial material parameters required for the occurred problems when using bonding as joining method. The results from the experiments and literature survey are used to simulate different bonding methods with the commercial software Abaqus. Results from the simulation are presented using adhesive and tape as bonding methods. Finally it is shown, that it is most important for a successful bonding, where or respectively on which surfaces the bonding is done.

A smoke explosion is generally considered as a deflagration of the accumulated unburned fuel inside a closed compartment. However, the term smoke explosion has been widely misused for decades with a great deal of confusion, and very little research has been done towards this topic. The purpose of this research is to study the smoke explosion phenomenon in much more detail through the development of a fire scenario under various experimental conditions including ventilation size, fuel elevation and fuel mass, so that a more comprehensive understanding of this phenomenon can be achieved. A total of twenty experiments are carried out including both exploratory and final experiments. Thirteen experiments result in smoke explosions, among which there are five experiments result in more than one smoke explosion. A phenomenon referred as smoldering decay is observed in all experiments with smoke explosions, making it one of the precursors of the smoke explosion phenomenon. The smoldering decay is often indicated by an exponential decay of the temperature and is caused by the low oxygen concentration within the compartment. Based on the analysis, it is found that the vent size must be at least 50 mm in diameter in order for smoke explosions to occur. The fuel elevation has no influence on the occurrence of the smoke explosion. However when the fuel is placed near the ceiling, the temperature, the mass flow rate and the heat release rate are all lowered significantly. The size of the fuel also has no significant influence except for the duration of the experiment. The concentration of CO is scattered in the range of 1.9% and 4.3% when explosions occur. Hence, the accumulation of CO is considered not to be the direct cause for the smoke explosion. The triggering factor for smoke explosions is believed to be the flammable limit formed by the mixture of hydrocarbon and CO. The pressure difference caused by the explosion inside the compartment has to be at least 27 Pa for it to be considered as a smoke explosion.

Maintaining structural stability is an integral component of building fire safety. Stability must be ensured to provide adequate time for safe egress of the buildings occupants, fire fighting operations and property protection. Structural fire engineering endeavours to design structures to withstand the effects of fire in order to achieve this objective. The behaviour of reinforced concrete in fire is not as well understood as other construction materials, such as steel. This is in part due to the complexity of concrete material behaviour and also due to concrete’s reputation of superior fire performance. Concrete technology is, however, continually evolving; structures are increasingly slender, more highly stressed and have higher compressive strengths. A more robust understanding of concrete’s behaviour in fire will enable predictions of the implications of changing concrete technology and also help to properly quantify the fire safety risk associated with concrete structures. A fundamental key to understanding structural fire performance is the relationship between the thermal environment induced by the fire and the structure. Significant thermal variation has been found experimentally to exist within fire compartments. Despite this the design of structures for fire almost universally assumes the compartment thermal environment to be homogeneous. In this thesis the implications of compartment fire non-uniformity for concrete structural behaviour is investigated to assess the validity of the uniform compartment temperature assumption. The investigation is conducted using numerical tools; a detailed review of the necessary background knowledge, material modelling of reinforced concrete, finite element modelling of reinforced concrete structures and compartment fire thermal variation is included. The behaviour of a two-way spanning reinforced concrete slab is used as a structural benchmark. The membrane behaviour exhibited by two-way spanning RC slabs at high temperatures has been previously studied under uniform thermal conditions. They therefore are an ideal benchmark for identifying the influence of non-uniform thermal environments for behaviour. The relationship between gas phase temperature variation and concrete thermal expansion behaviour, which is fundamental to understanding concrete high temperature structural behaviour, is first investigated. These preliminary studies provide the necessary fundamental understanding to identify the influence of gas phase temperature variation upon the membrane behaviour of reinforced concrete slabs. The individual influences of spatial and temporal variation upon slab membrane behaviour are investigated and the behaviour under non-uniform thermal variation contrasted with uniform thermal exposure behaviour. The influence of spatial variation of temperature is found to be strongly dependent upon the structural slenderness ratio. The tensile membrane action of slender slabs is particularly susceptible to the distorted slab deflection profiles induced by spatial variation of gas temperature. Conversely the compressive membrane behaviour of stocky slabs is found to be insensitive to the deformation effects induced by spatial variation of temperature. The influence upon slender slabs is demonstrated under a range of temporal variations indicating that the thermal response of concrete is sufficiently fast to be sensitive to realistically varying distributions of temperature. Contrasting behaviour induced by uniform and non-uniform thermal exposures indicates that uniform temperature assumptions provide both conservative and unconservative predictions of behaviour. The accuracy of the uniform temperature assumptions was also found to be dependent upon the type of fire, for example, fast hot and short cool fires. Additionally, the sensitivity of structural performance to deformations caused by spatial variation of temperature demonstrated in this thesis challenges the purely strength based focus of traditional structural fire engineering. Spalling is an important feature of concrete’s high temperature behaviour which is not currently explicitly addressed in design. The incorporation of spalling into structural analysis is not, however, straightforward. The influence of spalling upon behaviour has therefore been dealt with separately. A spalling design framework is developed to incorporate the effects of spalling into a structural analysis. Application of the framework to case studies demonstrates the potential for spalling to critically undermine the structural performance of concrete in fire. It also demonstrates how the framework can be used to quantify the effects of spalling and therefore account for these in the structural fire design addressing spalling risk in a rational manner.

Chronic exertional compartment syndrome (CECS) of the lower leg, defined as a condition with exercise-induced pain due to increased intramuscular pressure (IMP), has previously mainly been described in running athletes, and etiologic factors are poorly described. CECS has not been reported to occur together with other diseases and information about consequences on muscles morphology after treatment with fasciotomy is largely unknown. We investigated etiologic and pathophysiologic aspects to CECS in a consecutive series of 63 patients with exercise-related leg pain and in 17 diabetic patients with symptoms of intermittent claudication but no circulatory insufficiency. Clinical examination, radiography, scintigraphy and IMP measurements at rest and after reproduction of symptoms were done. Patients with CECS were recommended treatment with fasciotomy. Biopsies were taken from the tibialis anterior muscle at time of fasciotomy and at follow-up 1 year later. For comparison muscle samples were taken from normal controls. Enzyme- and immunohistochemical and morphometric methods were used for analysis of muscle fiber morphology/pathology, fiber phenotype composition, mitochondrial oxidative capacity and capillary supply. Thirty-six of the 63 patients fulfilled the criteria for diagnosis of CECS in the anterior tibial compartment. The CECS patients could be divided into different etiologic groups: 18 healthy, 10 with history of trauma against the lower leg, 4 diabetic patients and 4 others. Only 5 of 36 CECS patients were athletes. The results after fasciotomy were good or excellent in 41 of 57 treated legs.  Sixteen of the 17 diabetic patients were diagnosed with CECS, 11 with diabetes type 1 and 5 with type 2. The diabetic patients differed from the other groups with longer symptom-duration, shorter pain-free walking distance, firm and tender lower leg muscles and higher IMP. The postoperative outcome was good or excellent in 15 of 18 treated legs. The muscle biopsies taken at fasciotomy showed frequent histopathological changes including small and large sized fibers, fiber atrophy, internal myonuclei, split fibers, fibrosis, disorganization of mitochondria in contrast to healthy CECS subjects having low muscle capillarization as the main finding. Muscular abnormalities were generally more complex, severe and widespread in diabetic patients. After 1 year, the majority of CECS patients could return to unrestricted physical activity and the histopathological muscle changes were clearly reduced. The muscle fiber size was larger and the muscles contained signs of regeneration and repair. Remaining muscle abnormalities were present mainly in diabetic patients. CECS is a new differential-diagnosis in diabetic patients with symptoms of claudication without signs of vascular disease. A low ability for physical activity, reflected by the signs of both myopathy and neuropathy, indicates that high IMP and circulatory impairment has deleterious effects for the involved muscles. Increased physical activity and normalization of muscle morphology 1 year after treatment shows the benefit of fasciotomy. The more severe clinical and morphological findings in diabetic compared to healthy subjects with CECS indicate differences in the pathogenesis. The unrestricted physical ability after treatment is very important for diabetic patients, since physical activity is an essential part of the therapy of the disease.

No description available.