Thesis (M. Phil.)--University of Hong Kong, 2007. / Title proper from title frame. Also available in printed format.

Thesis--University of Wisconsin--Madison. / Typescript. Vita. Description based on print version record. Includes bibliographical references (leaves 135-149).

Thesis (Ph. D.)--University of Wisconsin--Madison, 1981. / Typescript. Vita. Description based on print version record. Includes bibliographical references (leaves 215-229).

Thesis (Ph. D.)--College of William and Mary. / Vita. Includes bibliographical references. Also available via the World Wide Web.

Thesis--Stanford University. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

This thesis is focused attention on one-dimensional models for fast transient flows in a kinematic non-equilibrium. Besides the thermodynamic non-equilibrium, there is another type of non-equilibrium: the kinematic non-equilibrium, or drift between the phases. Such flow models include bubbly gas/liquid flows which are characterized by strong coupling between the phases, due to the rapid interphase transfers of mass, momentum and energy. As a consequence the assumptions that the phase pressures and the phase temperatures are equal at any cross-section appear consistent with experimental observations. The set of equations includes a momentum equation which has the form of a relaxation law of the drift velocity. This equation is based on a simplified version of the so-called Voinov - Berne equation for the momentum of the gas in a bubbly flow. The ability of the model to predict steady state critical flows is tested first. This is done by means of an analysis of the sensitivity to variations of the main parameters, and also by comparing the results with two sets of original experimental data on air-water critical flows. Finally, the model is tested in transient conditions, modelling the water hammer phenomena.

No description available.

The air-water flow reqime transitions in a horizontal pipe under the influence of a stronq electric field perpendicular to the interface are studied. The separated flow model to predict flow regime transitions has been developed. The present version of the model is a modification of Taitel and Dukler's separated flow model. This assumes that all flow reqimes are perturbations from stratified smooth flow. Expressions for the electrical force are derived and added to the conservation and constitutive equations to obtain new transition criteria. The theoretical results are compared with observations of air-water flow in a 1.27 cm. and 1.9 cm. internal diameter pipe. Good agreement was found when no electric field was applied, however, the experimentally observed effect of the electric field was not as pronounced as predicted by theory. Further experiments to refine the theoretical model are presented. / Thesis / Master of Engineering (ME)

Atmospheric transport and air-water exchange of organochlorine pesticides (OCPs) were investigated in temperate North America and the Arctic. OCPs studied were hexachlorocyclohexanes (HCHs, a-, b- and g-isomers), components of technical chlordane (trans- and cis-chlordane, trans-nonachlor), dieldrin, heptachlor exo-epoxide and toxaphene. Air and water samples were taken on cruises in the Great Lakes and Arctic to determine concentrations and gas exchange flux direction and magnitude. The Henry’s law constant, which describes the equilibrium distribution of a chemical between air and water, was determined for several OCPs as a function of temperature and used to assess the net direction of air-water exchange. Air samples were collected in Alabama to investigate southern U.S. sources of OCPs. Chemical markers (isomers, and enantiomers of chiral OCPs) were employed to infer sources and trace gas exchange. Elevated air concentrations of toxaphene and chlordanes were found in Alabama relative to the Great Lakes, indicating a southern U.S. source. Profiles of toxaphene compounds in air were similar to those in soil by being depleted in easily degraded species, suggesting that soil emissions control air concentrations. Gas exchange fluxes in the Great Lakes indicated near-equilibrium between air and water with excursions to net volatilization or deposition. Net volatilization of a-HCH from the Arctic Ocean was traced by evasion of non-racemic a-HCH into the atmosphere.

International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / During shallow water exercises, the performance of acoustic tracking and telemetry systems is degraded by severe multipath interference. The feasibility of an optical source attached to the underwater vehicle (UV) and a tracking aircraft-based receiver was theoretically established. Supporting water absorption and surface interaction experiments were also performed. The limiting case was the tracking of an unmanned underwater vehicle (UUV). The requirements of daylight operation, atmospheric visibility, limited space and weight, self-contained power, exercise duration, sample rate, optimum search area, robustness in varying scattering and sea states, non-cooperating (except for low-data-rate communications of information such as depth) source and receiver, and relative simplicity, lead to two optimum candidate systems. One system uses a commercially available 5 megawatt q switched and double laser diode pumped YAG laser operating at 532 nm and 1 Hz rep rates. The second system uses a pulsed (2 μsec) zenon flash tube. Both systems satisfy the robustness constraint by intentional beam spreading. A performance constraint of 10:1 signal to noon solar upwelling shot noise ratio was imposed. This constraint can be met for water depths of 10 and 5 absorption lengths, respectively, for the laser and incoherent systems. An optimum search diameter of approximately 700 meters (m) at an optimum aircraft elevation of 3,000 meters is calculated for both systems. The 4-inch diameter F/1 wide-angle light pulse detection system gates a 4-inch diameter F/1 intensified charged coupled device (CCD) imaging system that locates the light surface penetration point. Another candidate receiver that performs both functions is a positive sensitive photomultiplier tube with crossed wire anodes. A supporting night-time experiment has been designed and is under construction.