Thesis (M.S.)--Oregon State University, 2007. / Printout. Includes bibliographical references (leaves 51-52). Also available on the World Wide Web.

The aim of this thesis is to provide a design tool for the engineering analysis of the dynamics of a flexible riser system. The design tool is piovided in the form of a computer program. The two main requirements of such a program are that it is realistic and practical to use. The necessary theory is developed to allow these requirements to be satisfied. To ensure accuracy checks are made against model tests and known analytical solutions. How the computer program may be used is shown by analysing a particular riser configuration.

Dans le cadre d’une contribution à la modélisation des caloducs oscillants, le modèle mis en place se résume à une bulle seule se déplaçant dans un tube de dimension capillaire.Une densité volumique de chaleur est considérée dans la paroi du capillaire, et la température de référence considérée n’est pas la température de saturation de la phase vapeur,mais la température extérieure au tube ce qui permet la variation de la température de saturation dans le temps et une meilleur adéquation du modèle avec la réalité. La résolution du modèle est effectuée par étapes selon la technique de perturbation du domaine,et les effets physiques de moindres importances peuvent être ajoutés au problème simplifié, en particulier les effets inertiels. Cette résolution a permis de définir une nouvelle corrélation portant sur la hauteur de film déposé par le bouchon liquide en mouvement en fonction du nombre capillaire et d’un nombre d’évaporation représentant l’intensité du chargement thermique. Ce modèle permettra aussi d’étudier l’influence réciproque des champs de vitesse et de température sur le bouchon de liquide devant le ménisque en déplacement. La résolution du problème associé à la partie arrière de la bulle met en évidence la formation d’un bourrelet de liquide entre le film de liquide déposé à la paroi et le ménisque arrière. La taille de ce bourrelet est fortement dépendante de la densité de flux de chaleur imposée à la paroi. Dans le cas o`u le ménisque arrière remouille un film adsorbé laissé à la paroi après assèchement du film, la ligne triple présente des ondulations axiales dues à son déplacement, et non au chargement thermique. La densité de flux de masse évaporée à l’interface liquide-vapeur entraîne une modification non seulement de la température de saturation, mais aussi de la masse de la bulle. Un modèle thermodynamique de la phase vapeur a ´et´e mis en place pour étudier les paramètres importants influençant les variations temporelles des caractéristiques géométriques et thermodynamiques de la bulle. / The model of a single bubble moving in a capillary tube is written as a contribution to the modeling of Pulsating Heat Pipes. A constant heat load is considered at the wall, and the reference temperature of the problem is defined to be the outside medium temperature, which is closer to reality, and thus allowing the saturation temperature of the vapor phase to vary. Using domain perturbation techniques, a step-by-step resolution ofthe model is implemented, allowing minor physical effects to be taken into consideration,for example the inertial effect on the receding meniscus. A new correlation is proposed on the thickness of the liquid film deposited by the receding meniscus, by means of the capillary number and an evaporation number representing the thermal condition. The velocity and temperature fields in the liquid plug ahead of the meniscus can also be obtained. The resolution of the problem associated with the rear-end of the bubble,where the rear meniscus advances on either a micrometric liquid film or an adsorbed film left by the dry-out of the capillary wall, shows a corrugating liquid-vapor interface.The magnitude of these corrugations is strongly dependent on the value of the heat load applied at the wall. In the case of wall rewetting, the interface corrugations at the triple line are due to its displacement, and not to the thermal boundary condition. Because the evaporative mass flux through the liquid-vapor interface modifies the vapor bubble mass, a complete transient thermodynamical model of the bubble is implemented. In this case, the important parameters controlling the kinematics, dynamics and thermodynamics of the bubble were identified.

No description available.

Mass transfer between n-butanol and water has been studied in cocurrent pipeline flow. The apparatus consisted of a feed nozzle, a glass pipe contactor and a gravity settler. Compositions were determined by refractive index measurements. The variables studied were mass input ratio, total flow rate and contactor length. Pressure drop and holdup ratio also have been determined as a function of input ratio and total flow rate. Phase NTU's, determined directly by a method proposed by Colburn and Welsh (10), were found to correlate with individual phase velocities and also were dependent on the input ratio and the contactor length. Mass transfer stage efficiencies varied from near zero to nearly one-hundred per cent. The magnitude of the end effects was estimated by measuring the amount of mass transfer that occurred with virtually zero contactor length before settling. End effects were large. The pipeline contactor was compared to other experimental liquid-liquid extraction devices described in the literature, and was found to be superior in terms of "contactor effectiveness" and energy requirements. / Applied Science, Faculty of / Chemical and Biological Engineering, Department of / Graduate

D.Ing. (Mechanical Engineering) / The local buckling of axially loaded thin walled circular aluminium tubes is investigated in this work. Various buckling modes can be identified depending on certain geometrical ratios. Tubes with a thickness to diameter ratio of between 0,016 and 0,1 will buckle according to the so called axi-symmetric mode which is a very efficient collapse mechanism for energy absorbing purposes. Although there are numerous analytical solutions for this collapse mode the results are not fully descriptive. A finite-element model was developed and is described in this work. With this model it is possible to analyse the collapse mechanism in detail and the results obtained compare favourably with experimental values. When a relatively long thin walled tube is loaded axially it will undergo Euler buckling. This is not an effective collapse mechanism for energy absorbing purposes and a concept that overcomes this disadvantage is presented. With this energy absorber it is possible for axially loaded longthin walled circular tubes to collapse into a mode that resembles the axi-symmetric collapse mode. A finite element model was developed and successfully used to analyse the proposed concept. The results obtained correlate well with experimental values. A low speed impact test rig was designed, manufactured and commissioned. This rig was used to conduct dynamic tests on the proposed energy absorber and it was concluded that the proposed concept is viable for applications that require an inexpensive, reliable energy absorber with a long strokelength.

We review the definition and standard description of Thompson's Group F. We define the set of pipe diagrams and show that this set forms a group isomorphic to F. We use pipe diagrams to prove two theorems about giving a minimal representation for an arbitrary element of F.

In 1982 the Business Roundtable prepared several reports which investigated various aspects of construction which posed significant research opportunities. Their findings placed piping construction in the group of activities categorized as having "highest potential" for improvements based on inefficiency, or construction difficulty and proportionate costs. It was estimated that over $1 billion could be saved annually if the difficulty in the piping industry was improved to only average of other areas. Further investigation into the piping area showed that the alignment process took 20% of the cycle time for installation and ranked either first or second as compared to other task involved in pipe installation with regards to complexity, skills required and dependency on technical information. Based on the above, this research project was performed to develop a new technique to aid in the alignment process of underground gravity glow pipe. Included in the research was a detailed investigation into existing techniques for performing this task, establishment of a sample analysis to establish workable tolerances for pipe installation, the development of a laser-controlled excavation system and a cost analysis of the new technique presented. All technology used to develop this improved process consisted of currently available equipment used in other fields.

For many years, the construction industry in Sweden has not developed much of an integral approach for design across disciplines. The sector’s impact on society, economics and environment is huge. To make the interactions within the construction industry more efficient, a relatively new concept called BIM (Building Information Modeling) has been introduced. The idea with BIM is that the different actors of the construction industry will work through intelligent CAD software, with common file formats and more cooperation between different actors during the various steps of the building and construction process. The technical consultancy company WSP Sweden is working actively to implement BIM within the frame of its activities. One step towards BIM is the use of their visualization software Novapoint Virtual Map in a better way. They lack a good system to show which pipes belongs to different documents, i.e. some kind of status management. Another step towards BIM is to be able to change and revise Water and Sewage 3D-models with HVAC 3D-models, and to be able to detect possible errors in the connection nodes early in the designing stage. In this thesis work, a CAD-model has been created in Novapoint VA, the CAD software used to design pipe and sewage systems at WSP. The designed model is divided into many stages which creates many parallel documents at the same time. The model is visualized in Novapoint Virtual Map where functions for status management are created. With the help of grouping functions in the software it is possible to show pipes that belong to different documents at the same time. The more documents there are in the same model the longer it takes to create the model, which is something that could be improved in later editions of the software. In this paper, seven tests were carried on to examine how water and sewage pipes CAD-models created in Novapoint VA can be jointly revised with HVAC CAD-models created in MagiCAD. The result of the test shows that four of these tests can be used to revise the models. To use one of these methods, according to the BIM model, for changes and revisions of models can help avoid mistakes in connection points already at design stage.

xi, 265 leaves : photos., diags ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Mechanical Engineering, 1978