65,499 research outputs found
Sceloporus magister
Number of Pages: 4Integrative BiologyGeological Science
Recommended from our members
Phrynosoma solare
Number of Pages: 2Integrative BiologyGeological Science
Space technology's potential for industry
Space technology transfer to civilian applicatio
Longitudinal friction forces in piping design
Scheme measures sliding support friction forces and incorporates them into software programs which are used to analyze piping flexibility
Stability and Vortex Shedding of Bluff Body Arrays
The primary purpose of this study was to develop an understanding of the stability of laminar
flow through bluff body arrays, and investigate the nature of the unsteady vortex shedding regime
that follows. The flow was numerically investigated using a specially developed multi-domain
spectral element solver. Important criteria in the solver development were flexibility, efficiency, and
accuracy. Flexibility was critical to the functionality of the code, as arrays of varying geometry
were investigated. Efficiency with a high degree of accuracy was also of primary importance, with
the code implemented to run efficiently on today's massively parallel architectures.
Numerical two-dimensional stability analysis of the flow in several configurations of inline and
staggered array geometries was performed. The growth rate, eigenfunction, and frequency of the
disturbances were determined. The critical Reynolds number for flow transition in each case was
identified and compared to that of flow over a single body. Based on the solutions of the laminar
flow, a one-dimensional analytical analysis was performed on selected velocity profiles in the wake
region. The results of this analysis were used to guide the interpretation of the two dimensional
results and formulate a general theory of stability of inline and staggered bluff body arrays. The
nature of the flow in the unsteady regime following the onset of instability was examined for an
inline and a staggered arrangement. Particular attention was focused on the vortex shedding which
was visualized and quantified through computation of the flow swirl, a quantity which identifies
regions of rotary motion. The conditions required for the generation of leading edge vortex shedding
were identified and discussed. Finally, a third geometry related to the inline and staggered arrays
was considered. Flow solution data for this geometry is presented and its suitability as a model for
louvered arrays was discussed.Air Conditioning and Refrigeration Project 11
Pituophis melanoleucus
Number of Pages: 8Integrative BiologyGeological Science
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Facilitating Institutional Curriculum Change in Higher Education
This paper discusses the strategies and processes used within one Higher Education institution to support curriculum design and, change the culture around this activity. The paper provides a brief discussion of two institution wide projects related to curriculum design that have been taking place over the last few years and have been used to support this area of development. The discussion will then identify some of the issues around terminology and barriers to staff engaging in curriculum design as well as processes that had been used by staff and then move to discussing the strategies used to support this activity. Throughout the paper there will also be reference to comments gained from peers during the workshop that took place at the Eighteenth International Conference on Learning in Mauritius in July 2011
Spacecraft separation system for spinning vehicles and/or payloads Patent
Stage separation system for spinning vehicles and payload
An analysis at mesospheric coherent-scatter power enhancements during solar flare events
Solar flares produce increases in coherent-scatter power from the mesosphere due to the increase in free electrons produced by X-ray photoionization. Thirteen such power enhancements were observed at Urbana. When such an enhancement occurs at an altitude containing a turbulence layer with constant strength, the relative enhancement of electon density is estimated from the enhancement in power. Such estimates of enchanced electron density are compared with estimates of the X-ray photoionization at that altitude, deduced from geostationary satellite measurements. It is found that possible types ion-chemical reaction scheme may be distinguished, and the nonflare ion-pair production function may be estimated. The type of ion-chemical scheme and the nonflare ion-production function are shown to depend on the solar zenith angle
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