Dr. K. Reddy

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The thermal fouling data of Watkinson were recomputed on the assumption that increases in pressure drop were caused entirely by roughness of the fouling deposit and not at all by blockage. The results indicate that roughness played some role in the sand-water runs, but no role in the gas oil runs. The anomalous increases in overall heat transfer coefficient with degree of fouling in the first two sand-water runs were thus explained by the effect of roughness on liquid film heat transfer coefficient. The original loop was modified, the principal change being the replacement of the manual temperature recording system by a digital Data Logging System. Fluid and wall temperatures, as well as differential pressure, could thus be automatically recorded as a function of time. Better control of independent operating variables such as fluid velocity, inlet temperature and heat flux could therefore be achieved, and the effects of temporary fluctuations in these operating conditions could be observed and separated from fouling effects. Thermal fouling runs were made in the modified heat transfer loop on samples of Bayer Process spent liquor from the ALCAN aluminum refinery in Arvida, P.Q. The only discernible trends in the results were increases in rate and degree of fouling with increasing heat flux to a maximum value, followed by a sharp decrease, at liquor velocities less than 5 ft/sec, and the absence of thermally detectable fouling at higher velocities. The unreproducibi1ity of the results is believed to be attributable, at least in part, to changes in chemical composition of the liquor throughout the experiments. / Applied Science, Faculty of / Chemical and Biological Engineering, Department of / Graduate

The transient flow in pipe networks is represented by a pair of quasi-linear hyperbolic partial differential equations. The method of characteristics is used to transform these equations to a set of ordinary differential equations, which are then solved, by a first order finite difference technique using suitable boundary conditions. The main purposes of these investigations are: 1) To derive suitable boundary conditions or boundary condition equations for valves, sprinklers, surge tanks and air chambers, and 2) To investigate the effect of these boundary conditions on the transient flow in pipe systems. Several numerical examples are solved on the digital computer using the method of characteristics. The results are compared with those obtained by the graphical method. Although in this thesis the developed boundary conditions are used to study the transient response of the irrigation pipe systems, the boundary conditions, without any modification, can be used to determine the transient conditions in water supply pipe networks or in pipes carrying other liquids. / Applied Science, Faculty of / Civil Engineering, Department of / Graduate

Introduction: In 2014,Lamar and Mary Fowler Holcomb donated a collection of artifacts from the Native American site of Long Swamp to the Cherokee County Historical Society. Holcomb property is on land associated with the Long Swamp site (9CK1), which has allowed the two to gather artifacts from the site throughout the years. The rest of 9CK1 is on the opposite side of SR372. Edwards Pitman Environmental Inc. (EPEI), a local archaeological firm, was contacted in 2007 to investigate 9CK1 on public land, due to damage resulting from an extension of SR372. The archaeologists recovered artifacts in association with Long Swamp. In contrast to the excavation conducted by EPEI, the Holcomb maintained a minimal record of the artifacts they collected, voiding most of context associated with each artifact. Without contextual information, I rely on stylistic variables and to type the pipes. To do this, I compare the pipes from the donated collection to the other materials from Long Swamp and other archaeological sites in Georgia to ascertain the typology and chronology of the artifacts from the Holcomb Collection. Methods: The collection contains sixty-six pipes and pipe fragments. These pipes were measured with plastic, dial calipers, 150 mm/0.0254 mm. Weights were taken using a scale, max weight, 200 g. The pipes were photographed using a Nikon DX AF-S 18-55mm 1:3.5-5.6g D 5.100. Analysis also included a literature review and the investigation of pipes from archaeological collections housed at the University of Georgia, Athens and the University of West Georgia. Results: My analysis resulted in the creation of a typology for the pipes in the collection. Although none of the clay for the pipes was sourced, a cursory study of the different pipes suggests that multiple types of clay were used. Some of the more overt variations among pipe structures are the ratios between height and weight. These variations could indicate different craftsman, throughout time. Conclusion: The Lamar and Mary Fowler Holcomb Collection is the result of several years of collecting. The pipes within the collection appear to span several occupational phases of the Long Swamp site. This supports the findings of the previous research conducted at the site. However, with little contextual support, this can only be inferred based on stylistic attributes that can be compared to the materials from other collections. Further research into sourcing the clay for the pipes may prove useful to learn more about this collection.

Nous avons défini le complexe tabagique selon quatre champs applicables : les pipes à fumer, le tabac, le rôle du tabac dans les rapports Autochtones-Européens et dans les échanges. Le but de ce mémoire est de mieux saisir ce que les pipes à fumer de la période historique nous dévoilent dans le contexte de l’archipel montréalais. Le dépouillement des rapports de fouille a permis de retirer d’innombrables fragments de pipes à fumer que nous retrouvons dans les contextes archéologiques de l’archipel montréalais pour la période 1642−1760. Les récits d’époque nous informent sur les habitudes reliées à la consommation du tabac ainsi que les rôles du tabac et des pipes à fumer dans les relations entre Autochtones et Européens et des processus d’échange. Des recherches sur le tabac sont venues ajouter des éléments cruciaux à ces deux sources d’information. Cette étude a été limitée à l’archipel montréalais, plus une aire de 10 km autour de celui-ci. La période étudiée est de 1642 à 1760. Nous avons constaté que les fragments des pipes à fumer se retrouvent majoritairement dans les zones de contact démontrant ainsi l’importance de ces objets dans les échanges. Ces zones de contact sont les endroits où le métissage prend place. Le tabac, que nous ne pouvons dissocier des pipes à fumer, joue aussi un rôle majeur dans les relations amérindiennes-européennes. Des dons de Nicotiana tabacum ont permis de solidifier des liens de confiance primordiaux entre les deux groupes dans les processus d’échange. Le tabac et les pipes à fumer, ont aussi subit le processus de transfert culturel, mais, le degré varie selon le type de pipes à fumer. / We defined the smoking complex according to four applicable fields: smoking pipes, tobacco, Indigenous -European relations and the role of tobacco in trade. The purpose of this research is to better understand what smoking pipes reveal to us in the context of the Montreal archipelago. The review of the excavation reports allowed us to retrieve information regarding the innumerable fragments of smoking pipes that we find in the archaeological contexts of the Montreal archipelago for the period 1642−1760. The ethnohistorical publications inform us about the habits and customs related to the use of tobacco as well as the roles that tobacco and smoking pipes played in Indigenous-European relations and exchanges. Tobacco studies have also added crucial elements to these two sources of information. This study was limited to the Montreal archipelago, plus an area of 10 km around it. The study period is from 1642 to 1760. We found that the fragments of smoking pipes are mostly found in contact zones demonstrating the cultural importance of these objects. Nicotiana tabacum strengthened bonds of trust between the two groups. These contact zones are the places where métissage takes place. Inseparable from smoking pipes, tobacco also played a major role in Amerindian-European relations. Gifts of Nicotiana tabacum favoured consolidation between the two groups and built the primordial trust necessary in exchange processes. Tobacco and smoking pipes are also part of the process of cultural transfer, but to a variable degree according to the type of smoking pipes.

The cultural significance of effigy pipes among southeastern groups during the Mississippian period (A.D. 1000-1600) has yet to be fully understood. Recent studies, however, have provided new archaeological contexts for framing explanations of their possible use and distribution among such groups. Apart from conjectures about their use as ceremonial objects, selection for effigy pipes in the Mississippian Southeast was directly related to fluctuating environmental and demographic conditions under which such objects were manufactured and distributed. These conditions provided the appropriate context for their emergence as costly signaling devices through which elite or special interest groups advertised fitness levels, typically expressed in displays of power and prestige. As signaling devices, effigy pipes attained their widest distribution in the Southeast during a time of environmental and demographic stability. Their decline was primarily the result of increasing climatic instability and widespread demographic upheaval--events that precipitated major disruptions in commercial and economic relations.

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<p> An existing transient network model for wicked heat pipes was extended to incorporate the effects of axial heat transfer along the wall and wick, heat transfer in the surrounding media, and non-condensable gases in the vapour region. The thermal resistance of the different components was broken down into a larger number of smaller resistances in both axial and radial directions to account for the axial conduction and to handle non-uniform boundary conditions. Two sets of experiments were performed on copper-water wicked heat pipes to evaluate the effect of non-condensable gases, axial conduction, surrounding media and non-uniform boundary conditions. In the first set of experiments, the heat pipes were electrically heated at one end and cooled on the other end using a water jacket. This set of experiments was used to investigate the effect of non-condensable gases, axial conduction and surrounding media on the steady state and transient performance. The effect of the surrounding media was investigated by heating the heat pipe through two different sized aluminum blocks mounted around then heat pipe evaporator section. In the second set of experiments, the effect of using a finned condenser on the steady state performance of the heat pipes were tested in a wind tunnel. The condenser section of the heat pipes in this case was mounted in the test section of the wind tunnel and cooled at different air velocities. Three fin densities were tested along with a heat pipe with no fins. The model predictions of the steady and transient response of the vapour and wall temperature of the heat pipes were in good agreement with the experimental results. </p> <p> The presence of non-condensable gases inside the heat pipe increased the overall thermal resistance of the heat pipe. While the non-condensable gases did not notably affect the transient response during the heat-up phase, it significantly slows down the cool-down phase. The axial conduction through the pipe wall and the wick structure decreases the overall thermal resistance of the heat pipe. The axial conduction did not have a great influence on the time response during the heat-up phase, but was very important in the cooldown phase, especially with the presence of non-condensable gases. The wick structure was found to be the most dominant component in the transient performance of the heat pipe. The evaporator block was the dominant capacitance in the overall conjugate system, and significantly affects the transient response. The experimental results from the finned condenser study showed that the internal resistance increased slightly with the fin density. There was some nonuniformity in the condenser surface temperature at the locations of the fins. However, this non-uniformity did not propagate to other parts of the heat pipe. </p> / Thesis / Master of Applied Science (MASc)