Electrohydrodynamic Enhancement of Heat Transfer and Mass Transport in Gaseous Media, Bulk Dielectric Liquids and Dielectric Thin Liquid Films

Controlling transport phenomena in liquid and gaseous media through electrostatic forces has brought new important scientific and industrial applications. Although numerous EHD applications have been explored and extensively studied so far, the fast-growing technologies, mainly in the semiconductor industry, introduce new challenges and demands. These challenges require enhancement of heat transfer and mass transport in small scales (sometimes in molecular scales) to remove highly concentrated heat fluxes from reduced size devices. Electric field induced flows, or electrohydrodynamics (EHD), have shown promise in both macro and micro-scale devices. Several existing problems in EHD heat transfer enhancements were investigated in this thesis. Enhancement of natural convection heat transfer through corona discharge from an isothermal horizontal cylindrical tube at low Rayleigh numbers was studied experimentally and numerically. Due to the lack of knowledge about local heat transfer enhancements, Mach-Zehnder Interferometer (MZI) was used for thermal boundary layer visualization. For the first time, local Nusselt numbers were extracted from the interferograms at different applied voltages by mapping the hydrodynamic and thermal field results from numerical analysis into the thermal boundary layer visualizations and local heat transfer results. A novel EHD conduction micropump with electrode separations less than 300 µm was fabricated and investigated experimentally. By scaling down the pump, the operating voltage was reduced one order of magnitude with respect to macro-scale pumps. The pumping mechanism in small-scales was explored through a numerical analysis. The measured static pressure generations at different applied voltages were predicted numerically. A new electrostatically-assisted technique for spreading of a dielectric liquid film over a metallic substrate was proposed. The mechanism of the spreading was explained through several systematic experiments and a simplified theoretical model. The theoretical model was based on an analogy between the Stefan’s problem and current problem. The spreading law was predicted by the theoretical approach and compared with the experimental results. Since the charge transport mechanism across the film depends on the thickness of the film, by continuing the corona discharge exposure, the liquid film becomes thinner and thinner and both hydrodynamic and charge transport mechanisms show a cross-over and causes different regimes of spreading. Four different regimes of spreading were identified. For the first time, an electrostatically accelerated molecular film (precursor film) was reported. The concept of spreading and interfacial pressure produced by a corona discharge was applied to control an impacting dielectric droplet on non-wetting substrate. For the first time, the retraction phase of the impact process was actively suppressed at moderate corona discharge voltages. At higher corona discharge strengths, not only was the retraction inhibited but also the spreading phase continued as if the surface was a wetting surface

Research and Technology, 1989

Selected research and technology activities at Ames Research Center, including the Moffett Field site and the Dryden Flight Research Facility, are summarized. These accomplishments exemplify the Center's varied and highly productive research efforts for 1989

First CLIPS Conference Proceedings, volume 2

The topics of volume 2 of First CLIPS Conference are associated with following applications: quality control; intelligent data bases and networks; Space Station Freedom; Space Shuttle and satellite; user interface; artificial neural systems and fuzzy logic; parallel and distributed processing; enchancements to CLIPS; aerospace; simulation and defense; advisory systems and tutors; and intelligent control

Integrating Environmental Protection into ASEAN Trading System

Integrating environmental protection into ASEAN trading system is pivotal for ensuring long-term economic development and environmental sustainability. Due to its resource-based economy, ASEAN\u27s economic performance highly depends on the sustainable condition of the environment. The ASEAN approach prioritizing economic growth without environmental consideration leads to environmental degradation and economic loss. Many transboundary environmental problems in ASEAN result from unsustainable production methods aiming to maximize advantages in trade competition. There are growing international efforts in addressing production and process methods as a part of the sustainable development goal. Major trading partners of ASEAN increasingly employ unilateral environmental trade measures and environmental provisions in trade agreements to induce sustainable production in exporting countries. Despite its trade-restrictive characteristic and extraterritorial effects, the environmental trade measure can be justified on the environmental ground according to the WTO/GATT rules. Although ASEAN should integrate environmental protection for its own interest, the actual implementation depends on member states as ASEAN is a state-centric regional organization. The political regimes of member states prioritize economic growth over environmental protection, suppress civil participation, disregard human rights to the healthy environment, and insist on a strict application of the ASEAN Way, refusing any intervention in all internal affairs. The lack of democratic norms and human rights assimilation intensify the rule of non-intervention. As a result, ASEAN environmental governance remains weak without effective engagement. Therefore, to integrate environmental protection in trade, ASEAN needs to unlock the ASEAN Way impasse and become more people-centered by having ASEAN representatives democratically elected, enhancing participation from non-state actors, particularly environmental groups, and strengthening a linkage between environmental protection and economic development

The Sixth Alumni Conference of the International Space University

These proceedings cover the sixth alumni conference of the International Space University, coordinated by the ISU U.S. Alumni Organization, which was held at Rice University in Houston, Texas, on July 11, 1997. The alumni conference gives graduates of the International Space University's interdisciplinary, international, and intercultural program a forum in which they may present and exchange technical ideas, and keep abreast of the wide variety of work in which the ever-growing body of alumni is engaged. The diversity that is characteristic of ISU is reflected in the subject matter of the papers published in this proceedings. This proceedings preserves the order of the alumni presentations given at the 1997 ISU Alumni Conference. As in previous years, a special effort was made to solicit papers with a strong connection to the two ISU 1997 Summer Session Program design projects: (1) Transfer of Technology, Spin-Offs, Spin-Ins; and (2) Strategies for the Exploration of Mars. Papers in the remaining ten sessions cover the departmental areas traditional to the ISU summer session program

Whose Beijing? The construction of identity and exclusion in an era of social change

As China is undergoing a great social transformation, urbanization has brought millions of domestic migrants into Beijing. After the 2008 Olympics, long term Beijingers have started to express their hostility against the overwhelming population of domestic migrants. This thesis seeks to enlarge our understanding of the nature and dynamics of this local hostility in Beijing, as a case study of the construction of prejudice that results from social change. It is illustrated under a combined framework of Durkheim’s theories of social change and anomie, Allport’s theorizing about prejudice, and Elias’s writings on insiders and outsiders. In order to answer how and why local hostility happened recently in Beijing, I located my ethnographic research on a grassroots organization consisting of long term Beijingers. There are three main findings. First, social change provides the invention of new traditions and norms that long term Beijingers were able to adopt before migrants came and had the chance to get settled. This enabled long term Beijingers to express their hostility by claiming that the migrants were “uncivilized”. Second, urbanization and a series of urban reforms not only brought migrants into the city, but also disturbed the existing lifestyles of the long term Beijingers and made them feel relatively deprived. Nostalgic sentiments aroused among long term Beijingers blamed outsiders for their perceived deprivation. Thirdly, the civic participation that the grassroots organization encouraged did not significantly reduce their prejudice against outsiders. Instead, local hostility was veiled by active participation and was believed to be legitimate because of the support of the local power structure, the mainstream media, and by other government policies

The Advocate - Aug. 25, 1960

Original title (1951-1987)--The Advocate: official publication of the Archdiocese of Newark (N.J.)