Abstract To control an un-swept flying wing is problematic in some ways. One of the problems is that when the wing experiences a disturbance in yaw, it does not, since it has no tail, generate any torque in the opposite direction as a plane with a vertical stabilizer does. This thesis is foremost aimed at exploring one particular solution to this problem. One approach to this problem is to place the motors out on the wing and differentiate the thrust, to achieve the same torque as splitted elevons or a vertical stabilizer does. This is what NASA used on the flying unmanned wing HELIOS. Reducing the thrust on the right set of engines, and increasing the thrust on the left side can mean that the combined thrust is unchanged. And thus more fuel efficient, and increases endurance. This project’s main goal has been to construct a half scale model of the school project flying wing Solaris, and to configure a control system for the differentiated thrust as used on Helios. Thereafter conduct flight testing and evaluate the controllability of the wing in a number of flight conditions, this to get a sense of the wings characteristics and which parameters one should adjust to get the best controllability as possible. After numerous adjustments and test flights it was concluded that it is possible to construct and fly a wing in this configuration, with relatively simple means, with satisfactory results. That the torsional rigidity has great influence on the controllability were evident after the test flights. After redistribution of the components on the wing the conclusion could be made that the dihedral could be held within the structural limit of the wing. The results of this thesis will contribute to the project Solaris at Mälardalens University in Västerås, Sweden. The project was carried out at Mälardalens University. The test flights were conducted at the former Air Force base F-15 Flygstaden and Mohed in Söderhamn, Hälsingland. / Solaris

第22回名古屋大学年代測定総合研究センターシンポジウム平成21(2009)年度報告

Conventionally the size of the back clearance played a great importance on reducing the axial clearance by utilizing the concept that the decreased axial clearance results in lower axial force acting on the impeller. However, from the previous works on the effect of the back clearance on the hydrodynamic forces upon the semi-open impeller showed the opposite trend: increasing the back clearance results in the reduced axial loading. In this work, the CFD simulation of an entire pump and detailed analysis on the back clearance flow are performed. By utilizing the commercially available software, meshing and CFD simulations are performed. LDA data, unsteady pressure data, and pressure distributions on the housing are used to validate the CFD model. The flow field prediction of the back clearance flow is then compared with other researcher’s works of the gap flow analysis between the rotating and stationary disks. The flow field inside the impeller passage, which is very sensitive to the back clearance size, is also studied. The empirical equation for the leakage loss through the balance holes is produced using the CFD predictions.

Thesis (M.S.)--Oregon State University, 2002. / Typescript (photocopy). Includes bibliographical references (leaves 42-44). Also available via the World Wide Web.

A thorough understanding of Tibetan Plateau growth requires knowledge of the geological evolution of the Tibetan terranes as they were accreted to the Eurasian margin during the Phanerozoic. This dissertation research addresses the tectonic evolution of the southernmost of these, the Lhasa terrane of Tibet from the Late Jurassic to Eocene. The data and insights presented herein are the result of extensive geologic fieldwork in the northern and central Lhasa terrane of Tibet. In this work I present new geologic mapping and thermochronologic data that reveals a terrane scale passive roof thrust belt in the northern Lhasa terrane that accommodates significant upper crustal shortening without exhuming basement rocks. Through the development of a geospatially referenced database of igneous crystallization ages, I show that Cretaceous magmatism on the Lhasa terrane was not static, but exhibited significant temporal-spatial migrations. I interpret these movements as the result of variations in Neo-Tethyan slab dip and suggest that these variations are a major factor in shaping the Cretaceous tectonics of the Lhasa terrane. Finally, I present the Cretaceous-Eocene tectonic evolution of the Lhasa terrane that shows that the Lhasa terrane was above sea level and likely had attained significant elevation prior to the accretion of India to Eurasia and that the development of the high elevation Plateau developed outward from a central core, rather than from south to north as is commonly thought. These insights refute the widely held view that the Tibetan Plateau is the result of the Cenozoic Indo-Asian collision.

The present thesis is a comparative study of the hydrodynamic effects of a few deterministic microasperity shapes in a thrust slider application. Numerical study based on finite difference methods is used to find the trend of important tribological properties such as friction and leakage. Also, this work utilizes a distinctive and practical approach for comparison by considering constant load conditions, instead of constant film thickness, as is expected in an operating thrust bearing. The results are encouraging and clearly reveal the existence of a transition point for asperity area fraction where a reversal in trends for both the coefficient of friction and leakage is observed. The shapes of asperities affect leakage but, have a negligible effect on coefficient of friction; however, the size and the type of asperity (positive or negative) do influence it. The effects of orientation, on the other hand, are found both on the coefficient of friction and leakage. Triangular asperities exhibit an advantage over the other shapes in terms of leakage. In general, the impact of shapes is distinguishable, more at higher asperity area fractions in accordance with the geometrical differences.

No description available.

Thesis (M.S.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains vii, 106 p. : ill. (some col.), col. maps. Includes abstract. Includes bibliographical references (p. 100-103).

Thesis(M.S.)--Auburn University, 2006. / Abstract. Vita. Includes bibliographic references.

Thesis (M.Sc.) -- Memorial University of Newfoundland. / Typescript. Bibliography: leaves 137-147. Also available online.