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1	Aerodynamic Heating In Missile-Fin Gap Region Devon Fano (9174140) 28 July 2020 (has links) Large heat transfer rates are a major source of possible failure in flight vehicles due to increases in temperature being linked to weakening material properties. Aircraft in high-Mach number flow generate excessive aerodynamic heat that may increase temperatures above limits of structural integrity. Even without reducing speed or changing material, it is possible to mitigate heat transfer by altering vehicle geometry. The purpose of this thesis is to study the extent of heat transfer in gap regions of various sizes by computationally simulating flow over an idealized missile-fin configuration. Maximum levels of heat transfer are analyzed as well as surface distributions that identify key design points. The Department of Defense software package with computational fluid dynamics capabilities, Kestrel, was employed to use the Reynolds-averaged Navier-Stokes equations to simulate turbulent Mach~6 flow over the missile model. Results are compared to data obtained by the Air Force Research Laboratory via wind tunnel tests of the same flow. Experiments and simulations both found an order of magnitude increase in heat transfer when an offset fin was attached, but this heating could be reduced by minimizing the offset distance. Simulated baseline properties agreed very well with experimental measurements and simulations of the gap region more precisely identified the locations of maximum heating. Aerospace Engineering CFD High-Mach Number Heat Transfer SWBLI Gap Region Kestrel
2	Stratigraphy and depositional history of the Pantano Formation (Oligocene-early Miocene), Pima County, Arizona Balcer, Richard Allen January 1984 (has links) No description available. Geology, Stratigraphic -- Miocene. Geology, Stratigraphic -- Oligocene.
3	Stratigraphy and Depositional History of the Pantano Formation (Oligocene-Early Miocene), Pima County, Arizona Balcer, Richard Allen January 1984 (has links) The Pantano Formation comprises 1,250 m of alluvial, fluvial, lacustrine, and volcanic rocks deposited in a basin formed in response to regional extension during mid- Tertiary time in southeastern Arizona. During deposition, the locations and composition of sediment source areas varied as contemporaneous uplift occurred adjacent to the basin. The lower half of the formation was deposited as alluvial fans that prograded northward, westward, and southward; the upper half was deposited during southwestward retreat of alluvial fan deposition and the onset of lacustrine deposition. An andesite flow separates the two depositional regimes. Radiometric dates of 24.4 ± 2.6 m.y. B.P. for the andesite and 36.7 ± 1.1 m.y. B.P. for a rhyolitic tuff disconformably underlying the formation indicate that deposition occurred during Oligocene to early Miocene time. Proper stratigraphic sequencing and description, paleocurrent analysis, and gravel provenance study aided in understanding the depositional history of the formation. absolute age alluvial fans andesites Arizona Basin and Range Province basins Cenozoic dates environment geochronology igneous rocks interpretation lacustrine environment Miocene Neogene North America Paleogene Pantano Formation Pima County Arizona provenance rhyolites sedimentary basins sedimentary rocks sedimentation southern Arizona terrestrial environment Tertiary United States volcanic rocks Geology, Stratigraphic -- Miocene Geology, Stratigraphic -- Oligocene

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