218 research outputs found

    Heat transfer from cylinders in subsonic slip flows

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    The heat transfer in heated wires was measured using a constant temperature anemometer over a Mach number range from 0.05 to 0.4 and pressures from 0.5 to 8.0 atmospheres. The total temperature ranged from 80 to 120 F and the wire diameters were 0.00015, 0.00032, and 0.00050 inch. The heat transfer data is presented in the form of a corrected Nusselt number. Based on suggested criteria, much of the data was obtained in the slip flow regime. Therefore, the data is compared with data having comparable flow conditions. The possible application of the heat transfer data to hot wire anemometry is discussed. To this end, the sensitivity of the wires to velocity, density, and total temperature is computed and compared using two different types of correlations

    Evaluation of flow quality in two large NASA wind tunnels at transonic speeds

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    Wind tunnel testing of low drag airfoils and basic transition studies at transonic speeds are designed to provide high quality aerodynamic data at high Reynolds numbers. This requires that the flow quality in facilities used for such research be excellent. To obtain a better understanding of the characteristics of facility disturbances and identification of their sources for possible facility modification, detailed flow quality measurements were made in two prospective NASA wind tunnels. Experimental results are presented of an extensive and systematic flow quality study of the settling chamber, test section, and diffuser in the Langley 8 foot transonic pressure tunnel and the Ames 12 foot pressure wind tunnel. Results indicate that the free stream velocity and pressure fluctuation levels in both facilities are low at subsonic speeds and are so high as to make it difficult to conduct meaningful boundary layer control and transition studies at transonic speeds

    Experimental studies of hypersonic boundary-layer transition and effects of wind tunnel disturbances

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    Boundary layer transition data on cones and free stream disturbance levels were measured in a hypersonic wind tunnel and Mach 8 variable density hypersonic tunnel. Transition data were obtained by using different conical models and techniques for detecting the location of transition. The disturbance levels were measured by using hot wire anemometry and pressure transducers. The transition Reynolds numbers obtained from the tests correlated well when the fluctuating pressures measured at the surface of conical models were used as a correlating parameter

    Fluctuation diagrams for hot-wire anemometry in subsonic compressible flows

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    The concept of using 'fluctuation diagrams' for describing basic fluctuations in compressible flows was reported by Kovasznay in the 1950's. The application of this technique, for the most part, was restricted to supersonic flows. Recently, Zinovev and Lebiga published reports where they considered the fluctuation diagrams in subsonic compressible flows. For the above studies, the velocity and density sensitivities of the heated wires were equal. However, there are considerable data, much taken in the 1950's, which indicate that under some conditions the velocity and density sensitivities are not equal in subsonic compressible flows. Therefore, possible fluctuation diagrams are described for the cases where the velocity and density sensitivities are equal and the more general cases where they are unequal

    Enduring Legacy? Charles Tilly and Durable Inequality

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    This article assesses Charles Tilly’s Durable Inequality and traces its influence. In writing Durable Inequality, Tilly sought to shift the research agenda of stratification scholars. But the book’s initial impact was disappointing. In recent years, however, its influence has grown, suggesting a more enduring legacy

    Working towards inclusive physical education in a primary school: ‘some days I just don’t get it right’

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    © 2018 Association for Physical Education Background: In Aotearoa New Zealand, as it is internationally, there is a desire to ensure physical education is inclusive of all students regardless of their abilities. Yet, medical discourses associated with disability continue to position students who are perceived as not having the capacity to participate fully in traditional physical education programmes as the teacher’s ‘helper’, ‘helped’, or ‘helpless’. As a result, these students may have negative experiences of physical education and this can impact on future involvement in movement-related activities within school and community settings. Methodology: Drawing on the data from a larger critical participatory action research project, we explore how one primary school teacher, Joel, attempted to work more inclusively within physical education. Specifically, we draw from personal journaling, student work and records of dialogical conversations to shed light on Joel’s experiences. Conclusion: Joel’s experience demonstrates that there is not one singular solution to inclusion within physical education and it is a combination of actions that support this process. In Joel’s case, this included becoming a reflexive practitioner, getting to know his students, being receptive as opposed to respective to difference in positive ways rather than seeing this as limiting, working imaginatively to reconsider what constitutes learning in physical education, and sharing ownership for curriculum design and learning with his students. Working in this way illustrates how a multi-layered approach can make a difference to how all the students in a class experience inclusion, including students positioned as disabled

    Contextualizing students' alcohol use perceptions and practices within French culture: an analysis of gender and drinking among sport-science college students

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    Although research has examined alcohol consumption and sport in a variety of contexts, there is a paucity of research on gender and gender dynamics among French college students. The present study addresses this gap in the literature by examining alcohol use practices by men and women among a non-probability sample of French sport science students from five different universities in Northern France. We utilized both survey data (N = 534) and in-depth qualitative interviews (n = 16) to provide empirical and theoretical insight into a relatively ubiquitous health concern: the culture of intoxication. Qualitative data were based on students’ perceptions of their own alcohol use; analysis were framed by theoretical conceptions of gender. Survey results indicate gender differences in alcohol consumption wherein men reported a substantially higher frequency and quantity of alcohol use compared to their female peers. Qualitative findings confirm that male privilege and women’s concern for safety, masculine embodiment via alcohol use, gendering of alcohol type, and gender conformity pressures shape gender disparities in alcohol use behavior. Our findings also suggest that health education policy and educational programs focused on alcohol-related health risks need to be designed to take into account gender category and gender orientation
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